Physiology - Mcq Bank

Front 1

Which of these are vasodilator metabolites that relax arterioles and precapillary sphincter?

- Endothelium 1

- Lactate

- Thromboxane A2

- Circulating Na+ - K+ ATPase inhibitor

Back 1

Lactate

Front 2

What is bradykinin

Back 2

vasodilator peptide formed in plasma

Front 3

What is angiotensin II

Back 3

most potent vasoconstrictor known

acts directly on adrenal cortex, on peripheral noradrenergic neurons, water metabolism

Front 4

What is vasopressin

Back 4

one of the posterior pituitary gland hormones

main effect is water retention by kidney

Front 5

What is gastrin

Back 5

Polypeptide hormone produced by G cells of gastric antral mucosa

Stimulates gastric acid and pepsin secretion

Front 6

What is renin

Back 6

proteolytic enzyme secreted by the kidney into the bloodstream

It splits the end off one of the plasma proteins (renin substrate) to release decapeptide - angiotensin I

Front 7

ANP increase/decrease when ECF volume increase/decrease

Back 7

ANP increases when ECF volume increases

Front 8

How does ANP affect sodium excretion?

Back 8

It can increase sodium excretion by increasing glomerular filtration rate

Front 9

How does ANP affect BP?

Back 9

It lowers BP

Front 10

Dopamine acts on which receptors?

Back 10

Own receptors

Alpha

Beta 1

Beta 2

Front 11

Noradrenaline and adrenaline act on which receptors

Back 11

Alpha

beta1

Beta2

Front 12

Isoproterenol acts on which receptors

Back 12

Only beta 1 and 2 receptors

Front 13

Which vasoactive substances can be released in carcinoid syndrome?

Back 13

Serotonin

Bradykinin

Prostaglandin

Histamine

Front 14

Prostacyclin is derived from

Back 14

arachidonic acid

Front 15

Prostacyclin is produced by

Back 15

endothelial and smooth muscle cells in blood vessels

Front 16

Function of prostacyclin

Back 16

Vasodilator - promote flow

PLT aggregation

Front 17

How does prostacyclin affect renin secretion?

Back 17

Stimulates renin secretion by direct action on juxtaglomerular cells and indirectly by reducing blood pressure

Front 18

Name two factors that influence total cerebral blood flow

Back 18

Arterial pressure at brain level

Venous pressure at brain level

Front 19

Explain mechanism behind Cushing's reflex

Back 19

Increased ICP --> hypertension, bradycardia

This is because increased ICP stimulates vasomotor centre due to local accumulation of CO2

Front 20

Oxygen extraction fraction of coronary blood flow at rest and during exercise

Back 20

At rest- 70%

During exercise - 100%

Front 21

Coronary blood flow can increase up to how much during maximal exercise

Back 21

Up to 5-6x

Front 22

Maximal flow of coronary blood occurs during systole or diastole

Back 22

Diastole

Front 23

Stimulation of sympathetic cardiac nerves result in increased intracellular cyclic AMP - T/F

Back 23

True

Front 24

Stimulation of cholinergic vagal fibres to nodal tissue decrease potassium ion conductance - T/F

Back 24

False

Front 25

Depolarisation of the ventricular muscles starts on the right side of the interventricular system - T/F

Back 25

False

Front 26

The last part of the heart depolarised is the epicardial surface of the left ventricular apex - T/F

Back 26

False

Front 27

Right atrial systole precedes left atrial systole - T/F

Back 27

True

Front 28

Right ventricular contraction precedes left ventricular contraction - T/F

Back 28

False

Front 29

Right ventricular ejection precedes left ventricular ejection - T/F

Back 29

True

Front 30

Pulmonary valve closes before aortic valve - T/F

Back 30

False

Front 31

In atrial flutter, the atrial rate is 150-220/min - T/F

Back 31

False, atrial rate ranges from 200-400

Front 32

In atrial flutter, there is accelerated AV conduction - T/F

Back 32

False, associated with AV block

Front 33

In atrial flutter, heart rate is irregular

Back 33

False

Front 34

In atrial flutter, the ventricular rate can be slowed by carotid sinus pressure

Back 34

True

Front 35

What is WPW syndrome?

Back 35

combination of presence of congenital accessory pathway + episodes of tachyarrythmia

There is early activation of ventricles because impulses bypass AV node via accessory pathway

Front 36

Name one ECG feature of WPW syndrome

Back 36

paroxysmal atrial tachycardia

Front 37

In WPW syndrome, there is prolonged PR interval and prolonged QRS complex slurred on the upstroke

Back 37

False

Front 38

In WPW syndrome, circus movement tachycardia is usually initiated by an atrial premature beat

Back 38

True

Front 39

In WPW syndrome, the arrythmia commonly progresses to CHB

Back 39

False

Front 40

In WPW syndrome, AF is a life threatening arrythmia

Back 40

True

Front 41

QT interval varies inversely with _____

Back 41

heart rate

Front 42

Normal QT interval -

Back 42

In women, QTc is prolonged if > 460ms

In men, QTc is prolonged if >440ms

Front 43

QT corresponds to

Back 43

ventricular electrical systole

Front 44

Simple way to tell the difference between SVT and VT

Back 44

VT is usually broad complex

SVT is usually narrow complex

Front 45

Action of NA on coronary artery and why

Back 45

NA causes coronary vasodilation

This is because injection of noradrenaline produces vasodilator metabolites as a result of increased myocardial activity

Front 46

QT interval in setting of hypokalaemia

Back 46

QT interval APPEARS to be prolonged in hypokalaemia due to fusion of T wave and U wave

Thus QT interval is NOT prolonged in hypokalaemia. The QU interval is prolonged instead.

Front 47

Inotropes should ideally

Back 47

reduce afterload and preload

increase cardiac output and ejection fraction

Front 48

Failing LV shifts the Frank Starling curve to the ......

Back 48

A failing LV shifts the Frank Starling (stroke volume vs ventricular end diastolic volume) to the right and down due to decreased contractility.

Front 49

Failing LV would have which of the following parameters reduced?

- ejection fraction

- end systolic volume

- rate of rise of pressure at commencement of systole

- stroke volume

- systolic shortening of myocardial fibre length

Back 49

All of these parameters will be reduced except the end systolic volume which would increase.

Slower contraction means the rate of rise of pressure is decreased.

Stroke volume is reduced --> systolic fibre length shortening is reduced, ejection fraction reduced

Front 50

isovolumetric contraction of the LV occurs after closure of the aortic valve - T/F

Back 50

False

Front 51

isovolumetric contraction of the left ventricle is terminated at the T wave of the ECG

Back 51

False

T wave corresponds to ventricular relaxation

Front 52

isovolumetric contraction of the left ventricle is responsible for ejection of majority of the stroke volume - T/F

Back 52

false

Isovolumetric means no change in volume

Front 53

isovolumetric contraction of the left ventricle involves the most rapid change in pressure per unit time in the cardiac cycle

Back 53

True

Front 54

isovolumetric contraction of the left ventricle occurs during the first third of systole

Back 54

False

Front 55

Patients with severe aortic stenosis causing LV failure have poor outcomes from valvular surgery

Back 55

False

cardiac status is often dramatically improved because the large pressure gradient across the aortic valve is relieved and cardiac workload reduces

Front 56

Impaired LV function can persist after correction of aortic stenosis via surgery

Back 56

True

long term changes in LV failure due to pressure overload can persist

This includes pathological hypertrophy, fibrosis, vascular insufficiency and changes in myosin isoform expression

Front 57

in patients with mixed aortic stenosis and insufficiency due to rheumatic heart disease, deteoriating cardiac function can actually be improved by increased aortic systolic or diastolic pressure?

Back 57

Increased diastolic pressure of the aorta can actually improve cardiac function in this setting

Reduced aortic diastolic pressure seen with aoric incompetence can seriously compromise coronary blood flow

Front 58

Essential differences between systolic and diastolic heart failure

Back 58

- ejection fraction

- myocardial wall thickness

- end diastolic volume

- end systolic volume

Front 59

Systolic heart failure characterised by

Back 59

dilated ventricle i.e. increased end diastolic volume reduced ejection fraction which gives increased end systolic volume

Front 60

Diastolic heart failure characterised by

Back 60

reduced ventricular compliance

Hypertrophied and stiff ventricles require increased diastolic filling pressure to approach a normal end diastolic volume

Hypertrophied muscle has increased performance so ejection fraction is increased

Front 61

Systolic and diastolic heart failures have this in common

Back 61

both need increased diastolic filling pressure though mechanisms are different

Front 62

Congenital VSD is associated with

Back 62

Increased pulmonary blood flow (usually left to right shunting) --> increased volume load on right ventricle and pulmonary circulation -->

possible late right ventricular failure

possible late pulmonary hypertension

Front 63

What kind of murmur do you get in congenital VSD?

Back 63

pansystolic murmur

Front 64

Do you get cyanosed from birth with congenital VSD?

Back 64

Congenital VSD usually is left to right shunting (going down the pressure gradient)

Cyanosis requires delivery of deoxygenated blood to the left heart and thus to the systemic circulation (usually right to left shunting)

Front 65

What kind of valve pathology causes volume overload in left ventricle

Back 65

Need both aortic and mitral insufficiency

Front 66

What is a common cause of loud pericardial rub

Back 66

due to pericardial effusions commonly due to infectious pericarditis or due to collagen diseases

This s because the fluid is often rich in fibrin which can produce a loud rub

Front 67

Majority of patients with significant pulmonary thromboembolism show

Back 67

tachycardia and dyspnea

Front 68

Pulmonary artery flotation catheters diredctly measure

Back 68

CVP

pulmonary artery wedge pressure

cardiac index

Front 69

Strepkinase infusion can cause haemorrhage due to

Back 69

high levels of fibrin degradation products and hypofibrinogenaemia

Front 70

In the fetal circulation, blood from the SVC enters the LA via the patent foramen ovale

T/F

Back 70

False

Goes to the RA to preferentially enter the RV

Front 71

In the fetal circulation, haemoglobin in the umbilical vein is 80% saturated with oxygen

T/F

Back 71

true

Front 72

In the fetal circulation, IVC blood is directed via the ductus arteriosus to the head vessels

Back 72

False

ductus arteriosus connects the pulmonary arteries to the descending aorta after the artery to the head has branched off!!

Front 73

IVC receives blood directly from the ductus venosus in the the fetal circulation

t/f

Back 73

True

Front 74

Haemoglobin F in fetal blood has a lower P50 compared to haemoglobin A in maternal blooid

T/F

Back 74

True

Haemoglobin F is left shifted compared to haemoglobin A on the oxygen dissociation curve. It ha a lower p50 (3.6kpa) compared to adult haemoglobin (4.2kpa). This is advantageous as it will encourage oxygen binding from the placenta.

Front 75

Placental blood flow is about 20% that of fetal cardiac output

T/F

Back 75

False

About 45% of the fetal combined ventricular output is directed towards the placenga

Front 76

SVC blood in the fetus is preferentially directed into the pulmonary circulation

T/F

Back 76

True

Blood from SVC --> RA --> RV --> PA

Front 77

Equation that summaries Bernoulli's principle of blood flow

Back 77

Flowing blood has velocity and mass therefore it has kinetic energy i.e. KE = 0.5 mV2

total energy in moving blood = kinetic energy + potential energy

Front 78

What does the potential energy in a moving blood represent?

Back 78

Represents the lateral pressure it exerts on vessel walls

Front 79

Two important conceps in Bernoulli's principle of blood flow

Back 79

1. Blood flow is driven by the difference in total energy between two points

2. Kinetic energy and potential energy can be interconverted so that total energy remains the same

Front 80

From Bernoullis principle of blood flow, it can be derived that the sum of kinetic energy and pressure energy is constant

Back 80

True

Front 81

From bernoulli's principle of blood flow, it can be derived that energy lost in overcoming resistance is irreversible

Back 81

True

Front 82

From bernoulli's principle of blood flow, it can be derived that the pressure drop due to conversion of potential to kinetic energy is reversible

Back 82

True

Front 83

From bernoulli's principle of blood flow, it can be derived that in a narrow segment of blood vessel - the velocity flow and lateral wall pressure are reduced

Back 83

False.

Velocity increases as diameter decreases (velocity is inversely proportionate to diameter)

KE also increases (KE is proportional to velocity)

Therefore, potential energy (lateral wall pressure) decreases

Front 84

What is central venous pressure

Back 84

pressure of blood in the thoracic vena cava near the RA of the heart

Reflects the amount of blood returning to the heart and the ability of the heart to pump the blood into the arterial system

Front 85

mean venous pressure in the dural sinus is constantly negative

Back 85

False

While it is negative -

Magnitude of the negative pressure is proportional to the vertical distance above the top of the collapsed neck vein

Front 86

mean venous pressure in the foot is higher when standing still or walking

Back 86

standing still

Front 87

mean venous pressure in the foot when standing still is 50mmHg

Back 87

false

mean venous pressure at the ankle is 85-90mmHg when standing still

Front 88

mean venous pressure in the subclavian vein, as it crosses the first rib, is positive above atmospheric pressure, when lying down

Back 88

true

Front 89

High CVP can be caused by rapid fluid bolus

Back 89

True

Front 90

High CVP can be caused by PE

Back 90

True

Front 91

High CVP can be caused by tension pneumothorax

Back 91

True

Front 92

High CVP can be caused by supraventricular tachycardia

Back 92

False

Front 93

High CVP can be caused by cor pulmonale

Back 93

True

Front 94

On assuming the upright position, the arterial pressure at head level and the jugular venous pressure fall 20-30 mmHg

Back 94

False

The venous pressure at the head level drops rather than jugular venous pressure

Front 95

On assuming the upright position, cerebral vascular resistance is reduced

Back 95

True

Blood runs towards the feet, venous and arterial pressure both decrease

Front 96

On assuming the upright position, the brain tissue PO2 is maintained by autoregulation

Back 96

False

Autoregulation works on cerebral blood flow via a myogenic mechanism

Cerebral blood flow is most sensitive to pCO2 rather than pO2

Front 97

On assuming the upright position, cerebral O2 consumption is about the same as in the supine position

Back 97

True

Otherwise we would have hypoxic brain injury getting up

Front 98

Acclimitisation to altitude is associated with enhanced erythropoietin secretion and circulating red cell mass

Back 98

True

Front 99

Acclimtisation to altitude is associated with lactic acidosis in the brain causing....

Back 99

A fall in CSF pH to enhance the ventilatory response to hypoxia

Front 100

Acclimitisation to altitude is associated with an increase in....

Back 100

1. Tissue content of cytochrome oxidase

2. red blood cell 2,3 DPG which decreases oxygen binding affinity of haemoglobin (this rightward shift occurs in setting of chronic adaptation; acutely it is leftward shift)

Front 101

Extracellular oedema is not associated with...

A - high venous pressure

B - increased arteriolar resistance

C - low plasma protein content

D - increased capillary permeability

E - lymphatic obstruction

Back 101

B

Front 102

Negative gravitational forces acting in the body produces increased cardiac output

Back 102

True

Front 103

Negative gravitational forces acting on the body produces increase in cerebral arterial pressure

Back 103

True

Front 104

Negative gravitational forces acting on the body can cause ecchyomoses around the eyes

Back 104

True

Front 105

Negative gravitational forces acting on the body can cause mental confusion

Back 105

True

Front 106

Venous pressure in the veins of the foot increases on standing in all subjects - T/F

Back 106

True

Front 107

Venous pressure on the veins of the foot diminishes on exercise in normal subjects - T/F

Back 107

True

Front 108

Venous pressure on the veins of the foot fails to diminish on exercise in subjects with varicose veins but competent perforators - T/F

Back 108

False

Front 109

Venous pressure on veins of the foot remains elevated during exercise in subjects with incompetence of the perforators and valve of the deep veins - T/F

Back 109

True

Front 110

Venous pressure in the veins of the foot diminshes on elevation of the legs in all subjects - T/F

Back 110

True

Front 111

Sudden elevation of the arterial pCO2 is associated with raised intracranial pressure - T/F

Back 111

True

Front 112

Sudden elevation of the arterial pCO2 is associated with respiratory acidosis - T/F

Back 112

True

Front 113

Sudden elevation of the arterial pCO2 is associated with skin vasodilation - T/F

Back 113

True

Front 114

Sudden elevation of the arterial pCO2 is associated with an increased plasma bicarbonate level - T/F

Back 114

True

Front 115

The liver converts free fatty acids to _____

Back 115

ketones

Front 116

The liver converts ammonia to ________

Back 116

urea

Front 117

The liver synthesises VLDL - T/F

Back 117

True

Front 118

The liver synthesises somatomedin-C (IGF-1) - T/F

Back 118

True

Front 119

The liver stores glucose as ______

Back 119

glycogen

Front 120

The liver processes chylomicron remnants from the blood T/F

Back 120

True

Front 121

The liver is responsible for gluconeogenesis to maintain blood glucose concentration - T/F

Back 121

True

Front 122

metabolic functions of the liver include chemical modification and excretion of thyroxine - T/F

Back 122

True

Front 123

Abnormally high blood ammonia levels commonly found in hepatic coma are due to porto-systemic shunting of blood - T/F

Back 123

True

Front 124

Abnormally high blood ammonia levels in hepatic coma are due to reduced capacity for urea synthesis in the liver - T/F

Back 124

True

Front 125

Abnormally high blood ammonia levels in hepatic coma are due to bacterial production of ammonia in the gut - T/F

Back 125

True

Front 126

Abnormally high blood ammonia levels commonly found in hepatic coma are due to decreased hydrogen ion excretion by the kidney - T/F

Back 126

False

Front 127

Ammonia may be formed from _______ in the kidney

Back 127

glutamine

Front 128

Ammonia is taken up by _________ in the brain

Back 128

glutamic acid

Front 129

Ammonia is converted to ________ in the liver

Back 129

urea

Front 130

Ammonia is a substrate for urea production in the kidney - T/F

Back 130

False

Front 131

About 85% of bilirubin is formed from haemoglobin released by destruction of mature red blood cells which normally have a life span of 74 days - T/F

Back 131

False

RBCs have a life span of 120 days

Bilirubin formation is

- 85% from haemoglobin

- 15% from myoglobin, cytochromes, peroxidase

Front 132

Unconjugated bilirubin in plasma is filtered into the proximal convoluted tubules - T/F

Back 132

False

Unconjugated bilirubin binds tightly to albumin which prevents its excretion into urine.

Front 133

About 20% of bilirubin in the small intestine recirculates to the liver in the enterohepatic circulation - T/F

Back 133

False

90-95% of bile acids are absorbed from the small intestine, transported back to liver in the portal vein and re-excreted in the bile

Front 134

Unconjugated bilirubin rises in the plasma when there is excessive destruction of RBCs

T/F

Back 134

True

Front 135

Bile salts are largely reabsorbed from the _____________

Back 135

Terminal ileum

Front 136

The primary bile salts are ______ and _______

They are conjugated with _________ or __________ in the liver

Back 136

Primary bile salts are cholate and chenodeoxycholate

They are conjugated with glycine or taurine in the liver.

Front 137

Bile salts are synthesised from __________

Back 137

Cholesterol

Front 138

Bile salts are concentrated in the _________

Back 138

gallbladder

Front 139

About 90% of cholate and chenodeoxycholate which enter the small intestine are absorbed from the jejunum and recirculated back to liver - T/F

Back 139

False

Most bile salts are reabsorbed in the terminal ileum

Front 140

Bilirubin is normally transported in blood bound to ________

Back 140

albumin

Front 141

Bilirubin is normally converted to __________ in the small instestine

Back 141

urobilinogen

Front 142

Bilirubin is conjugated in the liver with ______

Back 142

glucuronic acid

Front 143

Bilirubin is formed in

Back 143

the reticuloendothelial system and bone marrow

Front 144

The bile pigment in greatest quantity recycling in the enterohepatic circulation is bilirubin - T/F

Back 144

False

Bile acids are the ones getting recycled in the enterohepatic circulation

Front 145

Bilirubin glucuronide is deconjugated by ______ in the intestine

Back 145

bacteria

Front 146

Cholesterol solubility in bile depends on the relative concentration of

Back 146

lecithin

Bile salts

Front 147

If bile is analysed chemically, what would be found in the highest concentration in the alkaline electrolyte solution?

Back 147

Bile salts

Front 148

Reabsorption of bile salt from the intestine leads to further secretion of bile - T/F

Back 148

True

Front 149

Active transport of NaCl out of gallbladder is the mechanism by which the bile is concentrated - T/F

Back 149

True

Front 150

A certain concentration of bile salt is required for formation of micelles - T/F

Back 150

True

Front 151

Bile salts are derived from waste products of haemoglobin breakdown

Back 151

False

They are synthesised from cholesterol

Front 152

If there is complete obstruction of the common bile duct, retained bile salts may cause skin itch - T/F

Back 152

True

Front 153

The liver forms cholic acid from which 10-20g of bile salts are formed daily - T/F

Back 153

False

The total bile salt production is 0.2-0.4g/day

Cholic acid represents 50% of total bile salt production

Front 154

Bile acids are converted into the colon to??

Back 154

Cholic acid is converted into deoxycholic acid

Chenodeoxycholic acid is converted into lithocolic acid

Front 155

about 90-95% of cholate and chenodoexycholate which enters the small intestine recycles in the enterohepatic circulation - T/F

Back 155

True

Front 156

Cholate and cheno-deoxycholate are passively reasorbed in the jejunum - T/F

Back 156

False

Most are absorbed in the terminal ileum via active transport

Front 157

Oesophagus is normally open or closed? At which ends?

Back 157

closed at both ends

Front 158

The lower oesophageal sphincter has a resting pressure of 5mmHg above gastric pressure - T/F

Back 158

False

The LES is at least 15mmHg above gastric pressure.

Front 159

The lower oesophageal sphincter exhibits tonic muscular activity unlike the body of the oesophagus - T/F

Back 159

True

Front 160

In achalasia, the absence of ganglion cells results in failure of adequate contraction in the lower oesophageal sphincter - T/F

Back 160

False

Achalasia is failure to relax causing dilatation of oesophagus.

It is due to deficiency of myenteric plexus at the LES, therefore control of release of NO/VIP is defective.

Front 161

Reflex relaxation of the lower oesophageal sphincter is integrated in the

Back 161

Nucleus tractus solitarius and dorsal motor nucleus of the vagus

Front 162

The stomach can receptively relax - T/F

Back 162

True

This relaxation takes place when the oesophageal peristaltic waves pass towards the stomach

Front 163

The stomach controls the rate of access of food to the small intestine - T/F

Back 163

True

Front 164

Stomach emptying is regulated by signs from both the _______ and ________

Back 164

stomach and duodenum

Front 165

Signals from the stomach for stomach emptying are -

Back 165

1. nervous signals - caused by distension of food

2. gastrin release - by antral mucosa in response to certain types of food within the stomach

Front 166

The stomach secretes lipase - T/F

Back 166

True

Front 167

The stomach secretes a factor contributing to erythrocyte formation - T/F

Back 167

True

It secretes an intrinsic factor which is essential for vitamin B12 absorption - in turn contributing to erythrocyte formation

Front 168

Removal of the ________ in the stomach would be expected to reduce the gastric acid secretion because ______

Back 168

antrum

because it produces hormonal stimulation for acid secretion

Front 169

Which parts of the stomach secretes the most HCl?

Back 169

the body and the fundus

Front 170

The secretion of acid from the stomach is reduced when chyme enter the duodenum - T/F

Back 170

True

Front 171

Parietal cells in the stomach produce

Back 171

hydrochloric acid and intrinsic factors

Front 172

Chief cells in the stomach produce

Back 172

pepsinogens and gastric lipase

Front 173

Pancreatic polypeptide in the duodenum causes pancreatic exocrine secretion - T/F

Back 173

False

Pancreatic juice secretion is under homronal control.

Front 174

Vagal stimulation ____________ gastric secretion of acid and pepsin

Back 174

Increases

Front 175

Resection of large segments of small intestine is associated with gastric hypersecretion of acid - T/F

Back 175

True

Front 176

Vagotomy abolishes gastric acid production - T/F

Back 176

False

It can only diminish acid production, not abolish

Front 177

Vagotomy abolishes gastric motility - T/F

Back 177

False

It reduces gastric motility, not abolish

Front 178

Physiological regulation of gastric secretion can be broken down into three different influences - name/describe them

Back 178

Cephalic - vagally mediated responses induced by CNS activity

Gastric - local reflex responses and responses to gastrin

Intestinal - reflex and homronal feedback effects on gastric secretion. This is initiated in the small intestine.

Front 179

Gastrin is produced by __________

Back 179

G cells in the gastric antral mucosa

Front 180

Gastrin stimulates ________ and _______ secretion

Back 180

gastric acid

pepsin

Front 181

Acid in the antrum inhibits gastric secretion via

Back 181

Feedback mechanism involving somatostatin

Front 182

Vagal stimulation increases gastric secretion of acid and pepsin, but not mucus - T/F

Back 182

False

Front 183

The _________ vagal trunk gives rise to the hepatic branches which enter the liver via the lesser omentum and the porta hepatis

Back 183

Anterior

Front 184

The main terminal branch of the anterior vagus nerve crosses the stomach........

Back 184

Distal to the incisura angularis about 5-6cm the pylorus

Front 185

Most of the fibres of the posterior vagus nerve terminate in the stomach - T/F

Back 185

False

The posterior vagus trunk gives off a large celiac branch that runs backwards along hte left gastric artery to the coeliac ganglion

Front 186

Some vagal fibres travelling to the parietal cell mass may sink into the muscular wall at

Back 186

the oesophagus some distance above the cardia

Front 187

Decrease in gastric antral pH to 2.0 ______ the release of gastrin

Back 187

inhibits

Front 188

Decrease in gastric antral pH to 2.0 occurs due to synergistic action of

Back 188

histamine, gastrin, acetylcholine

Front 189

Decrease in gastric antral pH to 2.0 will reflexively _________ gastric secretion

Back 189

inhibit

Front 190

Decrease in gastric antral pH to 2.0 will promote activity in inhibitory afferent fibres of the vagus - T/F

Back 190

False

Vagus outflow promotes gastric secretion

Front 191

The respiratory quotient of the stomach during gastric juice secretion is ________ because.....

Back 191

less than one

Because the stomach takes up more CO2 from the arterial blood than it puts into the venous blood

Front 192

How do you calculate the respiratory quotient?

Back 192

It is the ratio of CO2 produced to the volume of O2 consumed PER unit of time.

Front 193

A patient with pyloric stenosis due to an active duodenal ulcer has been vomiting most of his meals during the past week. He is hypokalaemia because

Back 193

1. loss of postassium into gastric juice

2. increased renal loss of potassium

Front 194

Prolonged vomiting from severe pyloric stenosis is associated with

Back 194

metabolic alkalosis

low pH of urine

low serum potassium

Front 195

Prolonged vomiting associated with complete pyloric obstruction is associated with an increase in alveolar ventilation - T/F

Back 195

False

It would be associated with decrease, to retain more CO2 to make more bicarb

Front 196

Prolonged vomiting associated with complete pyloric obstruction is associated with a rise in plasma chloride concentration - T/F

Back 196

False

It will result in hyponatraemia, and thus hypochloraemia

Front 197

Prolonged vomiting associated with complete pyloric obstruction is associated with a rise in CSF pressure - T/F

Back 197

False

Not related

Front 198

Prolonged vomiting associated with complete pyloric obstruction is associated with a rise in plasma bicarbonate concentration - T/F

Back 198

True

Front 199

What can result in an increase in the pH of duodenal contents?

Back 199

Secretin - released from duodenum in response to duodenal acidification.

Front 200

Function of secretin

Back 200

Secretin significantly increases pancreatic water and bicarbonate secretion.It also inhibits gastric acid output.

Front 201

Function of cholecystokinin

Back 201

Stimulates pancreatic enzyme secretion and contraction of gallbladder

Front 202

Function of microvilli in the small intestine

Back 202

Increases surface area aiding absorption

Front 203

Mucosal cells of the small intestine are formed from

Back 203

undifferentiated cells in the crypts of Lieberkuhn

Front 204

Peristalsis is the only type of movement demonstrated in the small intestine - T/F

Back 204

False

Segmental contraction + tonic contraction are necessary in the small bowel to prolong transit time + foster absorption.

Front 205

The frequency of small waves __________ from the jejunum to the ileum

Back 205

Decreases

Front 206

How much water is absorbed by the small and large intestine daily?

Back 206

8-9L

Front 207

Of the reabsorption of water, how much is absorbed by the small intestine and how much by the colon?

Back 207

8L in the intestine (6L in the jejunum and 2L in the ileum)

1L in the colon

Front 208

Potassium is ______ by the small intestine and _________ by the large intestine

Back 208

Absorbed

Secreted

Front 209

The absorptive surface of the small intestine is increased ___________ fold by the ___________, ___________, and _____________

Back 209

600 fold

valvulae conniventes, villi and microvilli

Front 210

What effect does diarrhea have on serum potassium level?

Back 210

Decreases

Front 211

Of the water absorbed by our intestines, how much is endogenous and how much is ingested?

Back 211

Endogenous ~ 7L

Ingested ~2L

Front 212

Breakdown of endogenous water production within the GI tract

Back 212

Salivary glands ~ 1.5L

Stomach ~ 2.5L

Bile ~ 500mL

Pancreas 1.5L

Small intestine ~ 1L

Front 213

The intestinal mucosa below the duodenum produces which of the following?

- Mucus

- Secretin

- CCK

- Isotonic intestinal secretion

Back 213

Intestinal glands of the jejunum produce secretin, CCK and mucus in an isotonic secretion.

As do glands in the duodenum.

Front 214

Substances that are maximally absorbed in the upper part of the small intestine (i.e. jejunum) are

Back 214

Water soluble and fat soluble vitamins EXCEPT vit B12

Long chain fatty acids

Sodium

Iron

Calcium

Chloride

Front 215

Vitamin B12 is maximally absorbed in the

Back 215

lower part of the small intestine

Front 216

Bile salts are maximally absorbed in the

Back 216

lower part of the small intestine

Front 217

Patients who under massive resection of the proximal small bowel are likely to develop peptic ulcer - T/F

Back 217

True

Because these patients have decreased secretion of secretin and gastric inhibitory polypeptide --> hypersecretion of acids

Front 218

Massive resection of the small bowel is associated with intractable diarrhea - T/F

Back 218

True

Front 219

Massive resection of the small bowel is associated with increased likelihood of renal stone - T/F

Back 219

True

Front 220

Massive resection of the small bowel is associated with hypergastrinaemia - T/F

Back 220

True

Front 221

Massive resection of the small bowel is associated with increased serum calcium - T/F

Back 221

False

Less calcium absorbed therefore decreased serum calcium

Front 222

Massive resection of the small bowel is associated with lower serum protein - T/F

Back 222

True

Front 223

Resection of the ileum markedly decreases the absorption of

Back 223

Vitamin B12 and bile salt

Fat soluble vitamins

Front 224

Fat soluble vitamin is usually absorbed in the jejunum and not in the ileum. Why does resection of the ileum decrease the absorption of fat soluble vitamins then?

Back 224

Because resection of ileum leads to decreased bile salt reabsorption, interrupting fat absorption in the jejunum

Front 225

Resection of the last metre of the small bowel might result in a macrocytic anaemia within months - T/F

Back 225

False

Usually takes years for anaemia to develop as your body needs to deplete the cobalamin reserve

Front 226

What gives the odour of the faeces?

Back 226

Smell of sulfides due to action of intestinal bacteria

Front 227

In blind loop syndrome, steatorrhea can occur because the proliferation of bacteria results in excessive oxidation of conjugated bile salts - T/F

Back 227

False

It occurs because overgrowth of bacteria disrupts digestive/absorptive processes. Therefore there is disruption in bile salt absorption and thus fat mal-absorption.

Front 228

In the blind loop syndrome, the harmful effects are cause by bacterial invasion of the small intestine - T/F

Back 228

True

Front 229

In the blind loop syndrome, steatorrhea can occur - T/F

Back 229

True

Front 230

In the blind loop syndrome, bacterial overgrowth can contribute to development of macrocytic anaemia - T/F

Back 230

True

Front 231

In the blind loop syndrome, jaundice is a feature - T/F

Back 231

False

Front 232

How can resection of terminal ileum cause steaorhoea?

Back 232

This is because 90-95% of bile salts are absorbed in the terminal ileum and recycled by the enterohepatic circulation.

Front 233

Diarrhea during enteral feeding tube may be due to excess volume of feed - T/F

Back 233

True

Front 234

Diarrhoea during enteral tube feeding may be due to hyperosmolality of feed - T/F

Back 234

True

Front 235

Diarrhoea during enteral tube feeding may be due to malabsoprtion - T/F

Back 235

True

Front 236

Diarrhoea during enteral tube feeding may be due to short bowel syndrome - T/F

Back 236

True

Front 237

The colon ensures the constancy of faecal content despite variation of diet - T/F

Back 237

True

Front 238

There is active transport of sodium out of the colonic mucosa - T/F

Back 238

True

Front 239

The colon has sterile content at birth - T/F

Back 239

True

Front 240

The colon secretes potassium and bicarbonate into the lumen - T/F

Back 240

True

Front 241

A narrowed segment of the distal third of colon is more likely to produce symptoms than a narrowed segment of the proximal third of colon - T/F

Back 241

True

The distal colon will have more solid faeces causing more stretch in the narrowed segments --> causing more symptoms

Front 242

Gastrin stimulates gastric mucosal growth - T/F

Back 242

True

Front 243

Cholecystokinin secretion by cells of the upper small intestine is enhanced by

Back 243

amino acids and fatty acids

Front 244

Secretin augments the action of _________

Back 244

cholecystokinin in producing pancreatic secretion of digestive enzymes

Front 245

gastric inhibitory peptide _________ the sensitivity of insulin response to raised blood glucose

Back 245

increases

Front 246

The common feature of gastrointestinal hormones - VIP, GIP, secretin and glucagon is

Back 246

they are all portions of similar amino acid sequences

Front 247

VIP stands for

Back 247

vasoactive intestinal peptide

Front 248

4 functions of VIP

Back 248

- it stimulates intestinal secretion of electrolytes and hence of water in the intestine

- relaxation of intestinal smoth muscle

- dilation of peripheral blood vessels

- inhibition of gastric acid secretion

Front 249

Which of these are not GI hormones?

1. glucagon

2. GIP

3. enterokinase

4. gastrin releasing peptide

5. CCK

Back 249

Enterokinase

Front 250

Secretin is a powerful stimulant of pancreatic enzymes - T/F

Back 250

False

It stimulates pancreatic alkaline water production

Front 251

Secretin inhibits gastric motility - T/F

Back 251

True

Front 252

Secretin is produced in the upper small intestine - T/F

Back 252

True

In the duodenum and jejunum

Front 253

Secretin inhibits gastric acid secretion - T/F

Back 253

True

By increasing the pH of duodenum --> feedback loop of gastrin to inhibit secretion

Front 254

Secretin is released by acid in the duodenum - T/F

Back 254

True

Front 255

Secretin is released by vagal stimulation - T/F

Back 255

False

Its secretion is increased by products of protein digestion and by acid bathing the mucosa of the upper small intestine

Front 256

Secretin is a stimulant of secretion from biliary and pancreatic duct cells - T/F

Back 256

True

Front 257

Secretin is responsible for a high chloride ion concentration in external pancreatic secretion - T/F

Back 257

False

High bicarbonate

Front 258

Secretin is secreted by cells in the duodenal mucosa - T/F

Back 258

True

Also in the jejunum

Front 259

Secretin increases bicarbonate secretion from the exocrine pancreas - T/F

Back 259

True

Front 260

Secretin _______ gastrin secretion

Back 260

Decreases

Front 261

Secretin augments the action of ______ on the pancreas

Back 261

CCK

Front 262

Secretin is secreted when protein breakdown products arrive in the upper small intestine - T/F

Back 262

True

Front 263

Secretin increases the secretion of bicarbonate from the biliary tract - T/F

Back 263

True

Front 264

Secretin is released in conjunction with substance P - T/F

Back 264

False

Front 265

What is substance P?

Back 265

a GI peptide found in endocrine and nerve cells in the GI tract. It increases motility of small intestine.

Front 266

Secretin is structurally similar to glucagon - T/F

Back 266

True

Also similar to VIP, GIP

Front 267

Somatostatin inhibits acid secretion because

Back 267

1. inhibits gastrin release into bloodstream

2. inhibits parietal cell function

Front 268

CCK secretion is increased by

Back 268

1. Contact of intestinal mucosa with products of digestion, amino acids, and peptides

2. Fatty acids in the duodenum

Front 269

CCK has a more marked effect on the ducts than on the acini of the pancreas - T/F

Back 269

False

It acts on the acinar cells to cause release of zymogen granules and production of pancreatic juice rich in enzymes but low in volume

Front 270

CCK exerts a trophic effect on the pancreas - T/F

Back 270

True

Front 271

CCK inhibits the action of secretin in producing secretion of an alkaline pancreatic juice - T/F

Back 271

False

They augment each other

Front 272

Serum gastrin is decreased by products of protein digestion in the stomach - T/F

Back 272

False

It is increased

Front 273

Serum gastrin is increased by hypercalcaemia - T/F

Back 273

True

Front 274

Serum gastrin is low in pernicious anaemia - T/F

Back 274

False

In pernicious anaemia, the acid secreting cell is damaged so it can't sense that there is too much acid --> chronically elevated serum gastin

Front 275

Serum gastrin is increased after massive small bowel resection - T/F

Back 275

True

There is decreased secretion of secretin + GIP --> less inhibitory effect to gastrin

Front 276

Gastrin is produced in

Back 276

the G cells principally in the gastric antrum

Front 277

Gastrin stimulates

Back 277

HCL secretion by parietal cells of the fundus

Trophic effect on gastric mucosa

Front 278

Gastrin is mainly inhibited by

Back 278

secretin

Front 279

At what pH is the stimulation on gastrin shut off?

Back 279

1.2 in the antrum

Front 280

Gastrin is functionally and structurally related to CCK - T/F

Back 280

True

Front 281

Gastrin is secreted by antral mucosa - T/F

Back 281

True

Front 282

Gastrin is liberated by distension of the antrum - T/F

Back 282

True

Stretch receptors in the wall of the stomach and in the gastric mucosa sense distension --> release gastrin

Front 283

Gastrin stimulates secretion of both acid and pepsin - T/F

Back 283

True

Front 284

Circulating gastrin levels are _____ in Zollinger-Ellison syndrome

Back 284

high

Front 285

Circulating levels of gastrin are ____ in pernicious anaemia

Back 285

high

Front 286

Circulating levels of gastrin are _____ in secretory tumours of the pancreatic delta cells

Back 286

Low

Secretory tumours of pancreatic delta cells = somatostatinomas = inhibitory effect on gastric acid production

Front 287

Circulating levels of gastrin are _________ in most patients with duodenal ulcer

Back 287

Normal

Many studies show a normal level of serum gastrin in most patients with duodenal ucler

Front 288

Gastrin secretion is increased by which of the following

- glucagon

- calcium

- secretin

- tryptophan

Back 288

- calcium and tryptophan (an amino acid)

- not much evidence of gastrin and glucagon relationship

- gastrin secretion is inhibited by secretin

Front 289

Gastrin is present in which of the following tissues

- gastric antrum

- gastric fundus

- first part of duodenum

- renal parenchyma

Back 289

Gastric antrum

First part of duodenum (in very small concentration)

Front 290

VIP potentiates the action of acetylcholine in the salivary gland - T/F

Back 290

True

Front 291

VIP is formed from prepro-VIP - T/F

Back 291

True

Front 292

VIP inhibits gastric acid secretion - T/F

Back 292

True

Front 293

VIP causes vasoconstriction of peripheral blood vessels - T/F

Back 293

False!

Vasodilation

Front 294

CCK _______ the sphincter of oddi

Back 294

relaxes

Front 295

CCK stimulates enzyme rich pancreatic juice and stimulates alkaline pancreatic solution rich in bicarbonate - T/F

Back 295

False

It does stimulate enzyme rich pancreatic juice.

Secretin is the one that stimulates alkaline pancreatic solution

Front 296

CCK stimulates hepatic flow of bile - T/F

Back 296

True

Front 297

CCK _______ the gallbladder

Back 297

contracts

Front 298

Fat absorption is greatest in

Back 298

the upper small intestine

Front 299

Fat absorption occurs via

Back 299

passive diffusion into enterocytes

Some evidence showing that carriers are involved

However, NOT active absorption

Front 300

What percentage of dietary fat is absorbed in adults?

Back 300

95%

Front 301

What percentage of dietary fat is absorbed in infants?

Back 301

85-90%

Front 302

Small amounts of medium and larger chain fatty acids are absorbed directly into the portal blood - T/F

Back 302

False

Only fatty acids of less than 10-12 carbon atoms (small chains) are water soluble enough to pass through the enterocyte unmodified and absorbed into the portal bllod

Front 303

Chylomicrons are small droplets of fat combined with apoproteins which aid diffusion through enterocyte membranes - T/F

Back 303

False

Chylomicrons are breakdown products of longer chain fatty acids which are then coated with layer of protein, cholesterol and phospholipid

Front 304

Without bile acid, less than 15% of fat will be normally absorbed

Back 304

False

Bile acids are mainly to do with fat digestion rather than absorption

Front 305

Between 80-90% of all fat absorbed from the gut is transported to the blood

Back 305

As chylomicrons via the thoracic duct

Front 306

How are micelles formed?

Back 306

Bile salt + fatty acids + monoglycerides

Front 307

In the absence of bile salts, fatty acids are not absorbed

Back 307

False

Absence of bile salt leads to impairment of fat digestion

Front 308

Fatty acids containing more than 10-12 carbon atoms are ___________ in the mucosal cells

Back 308

Re-esterised to triglycerides

Front 309

Pancreatic lipase breaks down dietary triglycerides to form

Back 309

fatty acids and monoglycerides

Front 310

What proportion of calories a day can be parenterally administered as a fat?

Back 310

15-30%

Front 311

There is a specific requirement of short-chain fatty acid triglycerides to be provided in doses adequate in parenteral administration to generate ketone bodies for metabolism - T/F

Back 311

False

No specific requirement for short chain fatty acids

Front 312

Omega-6 polyunsaturated fatty acid triglyercerides should be provided in doses adequate to prevent essential fatty acid deficiency - T/F

Back 312

True

Front 313

There is a specific requirement for medium chained triglyercieds to maintain the fluidity of membranes - T/F

Back 313

False

There is no specific requirement

Front 314

Omega-3 polyunsaturated fatty acids may modulate the immune response - T/F

Back 314

True

Front 315

Omega-3 polyunsaturated fatty acids may modulate immune response by inhibiting induction of free radical lipid peroxides - T/F

Back 315

False

It modulates via three mechanisms

1) increasing membrane fluidity

2) INDUCING free radical lipid peroxides

3) providing precursors for eicosanoid metabolism

Front 316

What is the largest energy store following fat?

Back 316

muscle protein

Front 317

After a fatty meal, what happens to most of the fat in the intestine?

Back 317

It gets transported away as emulsified particles in the lymph

Front 318

Fat in the duodenum _______ stomach emptying because....

Back 318

Delays

Because fat in the duodenum releases CCK, secretin and GIP

Front 319

Plasma cholesterol can be decreased by which of the following

- thyroxine

- androgen

- oestrogen

- growth hormone

Back 319

Only two - thyroxine, oestrogen

Front 320

Endogenously derived triglycerides in the plasma is primarily transported as

Back 320

very low density lipoprotein (VLDL)

Front 321

Endogenously derived triglycerides in the plasma can be increased by carbohydrate excess in the diet - T/F

Back 321

True

Front 322

Endogenously derived triglycerides circulating in the plasma is removed from the circulation by

Back 322

muscle and adipose tissue

Front 323

Endogenously derived triglycerides in the plasma is increased when the plasma cholesterol level increases - T/F

Back 323

False

The level of endogenous triglycerides does not correlate with plasma cholesterol level.

Front 324

LDL contains _______ cholesterol than HDL

Back 324

more

Front 325

LDL contains ___________ triglyceride than HDL

Back 325

more

Front 326

Individuals with elevated LDL have _________ than normal incidence of atherosclerosis

Back 326

higher

Front 327

Individuals with elevated HDL have _________ than normal incidence of atherosclerosis

Back 327

lower

Front 328

The primary function of HDL is

Back 328

in cholesterol exchange and esterification

Front 329

Iron absorption is facilitated by pancreatic juice - T/F

Back 329

False

Front 330

Iron absorption is ________ by cereal products

Back 330

Inhibited

Phytic acid in cereal products reacts with iron to form insoluble compound int he intestine

Front 331

Iron absorption is_________ by adding ascorbic acid to the diet

Back 331

Increased

Front 332

Iron absorption is predominantly in the ________

Back 332

Duodenum

Front 333

Iron absorption is ___________ by low pH gastric secretions

Back 333

Increased

Front 334

Iron absorption is increased in states of iron overload - T/F

Back 334

False

Front 335

Iron absorption requires presence of transferrin - T/F

Back 335

True

Front 336

Iron absorption occurs in the terminal ileum - T/F

Back 336

False

Occurs in the upper small intestine

Front 337

Iron absorption is inhibited by pH of pancreatic juice - T/F

Back 337

False

Alkaline conditions REDUCE but do not inhibit iron absorption

Front 338

Iron absorption is inhibited by phytic acid - T/F

Back 338

True

This occurs in cereal.

Front 339

Iron absorption is inhibited by ascorbic acid - T/F

Back 339

False

It is enhanced by ascorbic acid

Front 340

Iron absorption is inhibited by phosphates - T/F

Back 340

True

Front 341

Iron absorption is mainly in the ferrous form - T/F

Back 341

True

Front 342

Adult males require iron absorption of _________ per day

Back 342

0.5-1mg

Front 343

Haemosiderin is the principal form of iron storge in the tissue - T/F

Back 343

False

70% in haemoglobin

3% in myoglobin

Remaining in form of ferritin

Front 344

A 50 year old man has a past history of duodenal ulcer and has been taking aspirin Q4H for painful RA for period of two months. This has caused a loss of 30mL of blood daily in his stools. It is likely that

1. his blood will show iron deficiency anaemia

2. his absorption of iron from a full normal diet will be affected by arthritis

3. his plasma iron binding capacity will be decreased

4. There will be no suspicion of malaena on macroscopic examination

Back 344

1. True

2. True

3. False (it will be increased)

4. True

Front 345

How much blood needs to be lost daily into the large intestine for malaena to be evident?

Back 345

More than 100mL

Front 346

Iron deficiency may occur in patients who have had radical gastrectomy - T/F and why

Back 346

True

Because there are less gastric secretions to convert dietary Fe3+ (ferric) forms to its more easily absorbable Fe2+ (ferrous) form

Front 347

Iron deficiency anaemia is a recognised complication of partial gastrectomy because acid is required for iron absorption within the stomach - T/F

Back 347

False

Acid enhances iron absorption but is not required

Front 348

S. Following total removal of stomach microcytic anaemia is likely to develop because

R. a secretion from the stomach is essential for erythropoiesis

Back 348

S. is true

R. is false - intrinsic factor is essential for vitamin B12 absorption and this is essential for normal erythropoiesis. However, this will cause a macrocytic anaemia.

Front 349

Gastric acidity is required for absorption of haem-iron - T/F

Back 349

False

It helps but is not required

Front 350

Achlorhydria leads to a significant reduction in absorption of non-haem-iron

Back 350

True

Less chloride ion is less hydrogen ion. This can lead to less absorption.

Front 351

Iron absorption does not increase after haemolysis - T/F

Back 351

True

Front 352

Iron absorption increases after haemorrhage - T/F

Back 352

True

Front 353

Patients suffering from pernicious anaemia have normal serum gastrin levels - T/F

Back 353

False

They have increased serum gastrin level

Front 354

There is no increase in gastric intra-luminal acid in pernicious anaemia - T/F

Back 354

True

Front 355

Pernicious anemia is associated with a ________ PCV

Back 355

Reduced

Even though the red cells are larger than normal, there's less of them. Thus the PCV is low

Front 356

Pernicious anaemia is typically associated with megaloblastic marrow - T/F

Back 356

True

Front 357

Pernicious anaemia is typically associated with gastric atrophy - T/F

Back 357

True

Front 358

Pernicious anaemia is associated with thrombocytopenia - T/F

Back 358

True

Front 359

The pancreas secretes insulin in increased quantity following alpha-adrenergic stimulation - T/F

Back 359

False

Alpha adrenergic stimulators (e.g. epinephrine, norepinehprine) inhibits insulin secretion

Front 360

Pancreas secretes proelastase - T/F

Back 360

True

Front 361

Pancreas secretes glucagon in decreased quantity following administration of somatostatin - T/F

Back 361

True

Front 362

Pancreas secretes inactive precursors of trypsin and lipase - T/F

Back 362

True

Front 363

The exocrine secretion of the pancreas contains phospholipase A - T/F

Back 363

True

Front 364

The exocrine secretion of pancreas contains ribonuclease and deoxyribonuclease to split nucleotides from nucleic acids - T/F

Back 364

True

Front 365

Exocrine secretion of pancreas contains chloride at about 130mmol/L concentration - T/F

Back 365

False

The concentration of chloride is about 55mmol/L

Front 366

Exocrine secretion of the pancreas contains prolipase from nucleic acids - T/F

Back 366

True

Front 367

External secretin of the pancreas contains a bile salt activated lipase capable of hydrolysing cholesterol esters - T/F

Back 367

True

Otherwise known as bile salt dependent lipase (BSDL)

Front 368

Bicarbonate rich pancreatic juice is secreted in response to

Back 368

secretin

Front 369

Enzyme rich pancreatic juice is secreted when

Back 369

CCK acts on pancreas

Vagal stimulation on pancreas

Front 370

Serum amylase can be raised in acute renal insufficiency - T/F

Back 370

True

Front 371

Serum amylase may be elevated during administration of morphine - T/F

Back 371

True

Front 372

Serum amylase may be elevated during acute perforation of a duodenal ulcer - T/F

Back 372

True

Front 373

Serum amylase may be elevated during mumps - T/F

Back 373

True

Front 374

In the absence of pancreatic enzymes the faeces contain more fat MAINLY because

Back 374

there is little enteric lipase in the epithelial cells of the small intestine

Front 375

If a carcinoma of the head of the pancreas obstructs the CBD, there is high level of urobilinogen in the urine - T/F

Back 375

False

Front 376

Urobilinogen entering the circulation is excreted in the urine - T/F

Back 376

True

Front 377

Protein has _________ caloric content than carbohydrate

In the body, protein has ___________ caloric values obtained compared to carbohydrates because.....

Back 377

higher

Similar

Because oxidation of protein is incomplete

Front 378

Name 4 evidences that intestinal absorption of carbohydrates is an active process.

Back 378

1. Transport of most monosaccharides can be blocked by metabolic inhibitors

2. Transport is selective for different monosaccharides

3. There is a maximum rate of transport for each monosaccharide

4. There is competition between certain sugars for respective carrier systems

Front 379

How much do patients require from parenteral administration of carbohydrate?

Back 379

25kcal/kg/day

Front 380

What proportion of total calories administered per day can be given as glucose?

Back 380

30-70%

Front 381

Butyrate, an endogenous product of fibre fermentation, is an important fuel for colonocytes - T/F

Back 381

True

Front 382

It is desirable to consume >250gm of fibre per day - T/F

Back 382

False

25-30gm

Front 383

A deficient fibre intake can lead to secretory diarrhea - T/F

Back 383

False

Deficient fibre leads to constipation

Front 384

The long term consumption of a diet that is low in fibre increases risk of bacterial translocation across the wall of the proximal colon - T/F

Back 384

False

No definitive evidence

Front 385

An inadequate fibre intake can impair the enter-hepatic circulation of bile salts and thereby lad to the diminished absorption of fat soluble vitamins - T/F

Back 385

False

Front 386

Ingestion of protein food such as eggs can sometimes provoke antibody formation in infants- T/F why?

Back 386

True

Infants absorb moderate amount of undigested protein which can enter circulation to provoke antibody formation

Front 387

Glycine should constitute at 50% of the amino acids in parenteral administration of protein - T/F

Back 387

False

Glycine is the simplest amino acid and is usually used as a "stuffer" amino acid

Front 388

Dosing should ensure that the BUN remains > 200mg/dL in parenteral administration of protein - T/F

Back 388

False

BUN should not exceed 100mg/dL - this is an indication for decreased dosing

Front 389

Hepatic encephalopathy is not influenced by the amount of protein that is administered parenterally - T/F

Back 389

False

Rising blood ammonia level is associated with clinical encephlopathy

Front 390

Parenteral nutritional solutions should contain at least 0.25g/kg/day of nucleotides to maintain proliferative ability of bone marrow - T/F

Back 390

False

A nutritional requirement of nucleic acid has not been established

Front 391

The protein requirement is about ______ per day

Back 391

1.2g-1.5g/kg

Front 392

cobalt deficiency can cause _______ anaemia

Back 392

megaloblastic

Front 393

iodine deficiency may cause

Back 393

goitre formation

Front 394

chromium deficiency may cause

Back 394

insulin resistance

Front 395

Is zinc an essential trace element?

Back 395

Yes

Front 396

Is copper an essential trace element?

Back 396

Yes

Front 397

Is beryllium an essential trace element?

Back 397

No

Front 398

Is molybdenum an essential trace element?

Back 398

Yes

Front 399

Is selenium an essential trace element?

Back 399

Yes

Front 400

Less than 5% of protein in the small intestine escapes digestion and absorption - T/F

Back 400

True

Front 401

Absorption of amino acids is rapid throughout the whole of the small intestine - T/F

Back 401

False

It is rapid in the duodenum and jejunum

There is no absorption in the ileum

Front 402

Over 90% of the digested protein is dietary - T/F

Back 402

False

50% comes from ingested food

25% comes from digestive juices

25% comes from desquamated mucosal cells

Front 403

Protein in the stools is largely undigested dietary protein - T/F

Back 403

False

Almost all protein in the stool comes from bacteria and cellular debris

Front 404

Amino acids are actively transported from the mucosal cells into the blood stream - T/F

Back 404

False

Amino acids have to go through transporters to enter enterocytes then into portal circulation.

Front 405

Branched chain amino acid administration to catabolic surgical patients enhances quality and number of polyribosome in skeletal muscle - T/F

Back 405

True

Its role in improving patient outcome is not defined. But compared to standard AA formulations, it can improve nitrogen retention and protein synthesis --> i.e. improving number and quality of polyribosomes in skeletal muscles.

Front 406

Branched chain amino acid administration improves patient outcome after major hepatic surgery - T/F

Back 406

False

Role in improving patient outcome is not defined.

Front 407

Branched chain amino acids are mainly metabolised in the liver - T/F

Back 407

False

It is mainly metabolised by skeletal muscles

Front 408

There is no role for parenteral branched chain amino acids therapy in patients with hepatic encephalopathy - T/F

Back 408

False

BCAA can be used in patients who are protein intolerant because of hepatic encephalopathy.

It permits greater protein intake without inducing encephlopathy than do standard protein formulas.

Front 409

When used clinically, branched chain amino acids should be administered at a dose of 0.1-0.3g/kg/d - T/F

Back 409

False

0.5-1.2g/kg/d

Front 410

The amino acid glycine is probably the mediator responsible for direct inhibition in the spinal cord - T/F

Back 410

True

Front 411

The amino acid glycine causes hyperpolarisation when directly applied to the membranes of neurons - T/F

Back 411

True

Front 412

The amino acid glycine with ________ and _______is responsible for synthesis of creatine in muscle - T/F

Back 412

Arginine

Methionine

Front 413

The amino acid glycine has an inhibitory function in the cord antagonised by atropine - T/F

Back 413

False

It is antagonised by strychnine

Front 414

When administered in pharmacologic doses, arginine may act as a neurotransmitter - T/F

Back 414

False

Front 415

Alanine is the main precursor of arginine - T/F

Back 415

False

Citrulline is the main precusor of arginine

Front 416

Critically ill patients require 30g/day of arginine - T/F

Back 416

False

The role of arginine in critically ill patients has yet to be defined.

Front 417

Arginine is the unique substrate for the production of nitrous oxide - T/F

Back 417

True

Front 418

Arginine is the preferred nutrient for immunocytes - T/F

Back 418

False

Its role as a immunomodulator is being evaluted.

Front 419

Glutamine is the only amino acid that contains 3 nitrogen molecules - T/F

Back 419

False

It has two

Front 420

Glutamine constitutes about 25% of the amino acid content of standard solutions of parenteral nutrients - T/F

Back 420

False

It is not included in the standard parenteral nutrients because it is unstable in solution and breaks down to form toxic amounts of pyroglutamate and ammonia.

Front 421

Critically ill patient require 20g/day of glutamine - T/F

Back 421

False

Not clear whether administering glutamine improves outcomes in catabolic patients.

Front 422

Glutamine is the principal fuel used by rapidly proliferating cells - T/F

Back 422

True

Front 423

The kidney consumes glutamine during period of metabolic alkalosis - T/F

Back 423

False

Kidney consumes glutamine during periods of metabolic ACIDOSIS

Front 424

Absorption of B12 requires two things - which two?

Back 424

1. intrinsic factor

2. trypsin to facilitate efficient absorption

Front 425

Arctic explorer shouldn't eat polar bear livers because

Back 425

they can develop headache, diarrhea and dizziness as they contain rich sources of vitamin A

Front 426

Sources of carbohydrate which may be used in parenteral nutrition solutions include

Back 426

glycerol

sorbitol

Not maltodextrins or starch

Front 427

Transport of glucose across intestinal cell membranes require -

Back 427

1. sodium transport across enterocyte membranes

2. carrier molecules

Front 428

If conscious, pain would be experienced in response to which of the following stimuli when applied to bowel:

1. visceral distension

2. surgical diathermy

3. visceral ischaemia

4. cutting with a sharp instrument

Back 428

Only visceral distension and ischaemia

Front 429

Uric acid is formed from breakdown of

Back 429

purines

Front 430

Uric acid reabsorption in renal tubules can be inhibited by

Back 430

probenecid

Front 431

Uric acid level in plasma is normally

Back 431

0.2-0.4mmol/L

Front 432

Uric acid urinary excretion is increased by allopurinol - T/F

Back 432

False

Allopurinol works by directly inhibiting xanthine oxidase in the purine degradation pathway. This then decreases uric acid production by preventing breakdown of purine.

Front 433

Serum albumin concentration of <30g/L is strongly correlated with poor clinical outcome - T/F

Back 433

True

Front 434

Albumin is a useful marker of nutritional status because it has a relatively short half life - T/F

Back 434

False

It has a half life of 28 days, so acute changes in serum albumin cannot be due to poor nutrition.

Serum albumin is not affected by starvation until starvation has reached an advanced stage

Front 435

Synthesis of albumin is markedly inhibited during early stages of undernutrition - T/F

Back 435

False

Serum albumin is not affected by starvation until it has reached an advanced stage.

Front 436

Albumin has a low exchange rate between intra and extravascular compartments - T/F

Back 436

False

It has a high exchange rate. Even small variations in percantage of exchange rate can cause variation in serum albumin.

Front 437

Serum albumin concentrations are increased during sepsis - T/F

Back 437

False