*** A&p Review Questions

Front 1

What happens in oxidation and reduction? Leo says ger

Back 1

Oxidation: atom loses an electron. Decrease in potential energy. Dehydrogenation (removal of hydrogens) liberated hydrogen transferred by coenzymes (NAD and FAD), glucose is oxidized in cellular respiration.

Reduction: atom gains an electron, increase in potential energy, O2 is reduced in cellular respiration.

- O2 is common electron acceptor.

- redox reactions always occur in pairs. One atom loses the electron, the other gains it and energy transferred from one to another.

- all molecules have stored energy potential in the bonds between their atoms.

Front 2

What is energy used for? (3)

Back 2

1. Immediate use by cells to conduct their normal metabolic processes (muscle contraction, secretions, active transport).

2. Synthesis of structural or functional molecules to repair and replace cells (mitosis and cytokinesis).

3. Storage (glycogen or fat) for later use as energy (nutrient reserves)

Front 3

Other ATP expenses (6)

Back 3

Locomotion, contraction, intracellular transport, cytokinesis, endocytosis, exocytosis.

Front 4

What is metabolism and what does it include (2)?

Back 4

Metabolism: total of all chemical reactions occuring in the body.

Includes: catabolism: break down complex molecules. Is exergonic: produces more energy than they consume. Anabolism: combine simple molecules into complex ones. Is endergonic: consumes more energy than they produce.

Front 5

What is ATP?

Back 5

Adenosine triphoshate. The energy currency. ADP + P- + energy= ATP

Front 6

What is the metabolism circle?

Back 6

* simple molecules such as glucose, amino acids, glycerol and fatty acids leads to anabolic reactions which transfer energy from ATP to complex molecules.

* complex molecules such as glycogen, proteins and TGs (releases heat) leads to catabolic reactions which transfer energy from complex molecules to ATP. Leading back to simple molecules (releases heat)

Front 7

What is the central feature of metabolism and energy transfer?

Back 7

Transfer of phosphoryl group: ADP + P- + energy= ATP.

Front 8

What is the reaction mechanism to transfer free energy in biological systems?

Back 8

Transfer of electron on oxidation reduction reactions. Oxygen is the strongest electron accessory in biological systems due to its electronegativity hence making it the strongest oxidizing agent.

Front 9

Glucose transporters (GluT) bring glucose into cell via

Back 9

Facilitated diffusion

Front 10

What causes insertion of more of these transporters?

Back 10

Insulin increasing rate of entry into cells.

Front 11

Describe protein metabolism

Back 11

Production of a protein molecule using an RNA model through a ribosome (translation), protein will then be modified through RER and golgi before secretion/use. Use of amino acids from digestion to build new protein.

Front 12

Protein catabolism

Back 12

PROTEIN CATABOLISM: proteins are digested in the gut into amino acids (hydrolysis of peptide bonds) which are then absorbed into blood and extracellular fluid. Excess proteins can serve as fuel like carbohydrates and fats. Nitrogen is removed producing carbon skeletons (oxidized) and ammonia (detoxified and excreted in urine), is highly toxic, but soluble, can be excreted by aquatic organisms as ammonia but terrestrial organisms must detoxify it first.

Front 13

Protein anabolism

Back 13

PROTEIN ANABOLISM: Transamination= adding an amino group (NH2) to pyruvic acid to produce any of the nonessential amino acids. Deamination: removing an amino group from an amino acid to form an acetyl molecule.

Front 14

Lipid metabolism, what is lipolysis, beta oxidation and lipogenesis?

Back 14

Lipolysis: break down TG in glycerol and 3 fatty acids (FA), glycerol enter glycolysis, FA are oxidized. Beta oxidation: break down FA into 2 carbon compound (acetyl CoA, cellular respiration). - oxidation of one 18-C stearic acid will net: 146 ATP. - glycerol nets: 22 ATP, so 1 triglyceride nets: 460 ATP. - by comparison: oxidation of 3 glucose (18 Cs) nets: 108 ATP. Lipogenesis: formation of lipids from non-lipids (glucose)

Front 15

What are lipoproteins?

Back 15

Lipoproteins: surrounding triglycerides with apoproteins to make them more transportable in water (carrier): - very low density lipoproteins (VLDLs)- low density lipoproteins (LDLs)- high density lipoproteins (HDLs)As found in the liver.

Front 16

The absorpitive state

Back 16

* Nutrient source: nutrients absorbed at digestive tract, to... * Distributed in bloodstream: lipids, amino acids, glucose, to... * Destinations: - ADIPOSE TISSUE: use: storage as triglyceridesStimulated by: insulin - SKELETAL MUSCLE: use: ATP production Stimulated by: insulin - ALL TISSUES: use: protein synthesis Stimulated by: insulin, GH, androgens/estrogens. - ALL TISSUES (EXCEPT SKELETAL MUSCLE: use: ATP production Stimulated by: insulin - LIVER AND SKELETAL MUSCLE: use: storage as glycogen Stimulated by: insulin *all are stimulated by insulin.

Front 17

The postabsorbitive state

Back 17

Nutrient source: Liver: lipid and amino acid breakdown.Stimulated by: glucocorticoids (1. Gluconeogenesis and 2. Glycogenolysis. Stimulated by: 1. Glucocorticoids and 2. Glucagon, epinephrine). Adipose tissue: triglyceride breakdown. Stimulated by: epinephrine, glucocorticoids. Skeletal muscle: protein breakdown by cathepsins. Stimulated by: glucocorticoids. Glycogen breakdown and glycolysis. Stimulated by: glucagon, epinephrine. Distributed in bloodstream: - ketone bodies- glucose - lipids - amino acids - lactic acid Destinations: All tissues: Use: ATP production Stimulated by: glucocorticoids Neural tissue: Use: ATP production All tissues (except neural): Use: ATP production Stimulated by: glucocorticoids Liver: Use: gluconeogenesis and ketone body production.Stimulated by: glucocorticoids Use: gluconeogenesis Stimulated by: glucocorticoids

Front 18

What happens when a person overeats?

Back 18

A. eating in excess of energy needs, body stores a small amount of glycogen and much larger quantities of fat.

Front 19

What happens when a person draws on stores (fasting)?

Back 19

B. nutrients from a meal are no longer available to provide energy (2-3 hrs after meal), body draws on its glycogen and fat stores for energy.

Front 20

What happens if the fast continues beyond glycogen depletion?

Back 20

C. (24hrs of starvation), body begins to break down its protein (muscle and lean tissue) to amino acids to synthesize glucose needed for brain and nervous system energy. Liver converts fats to ketone bodies, serving as alternative energy source for the brain, thus slowing breakdown of body protein.

Front 21

In energy metabolism, Define aerobic respiration, anaerobic respiration and fermentation

Back 21

- aerobic respiration: glycolysis to pyruvate decarboxylation to citric acid cycle to oxidative phosphorylation (electron transport chain + ATP synthase). - anaerobic respiration: electron acceptors are other than oxygen. - fermentation: glycolysis to substrate level phosphorylation (ABE, ethanol, lactic acid)

Front 22

Describe metabolism is specific parts

Back 22

- protein metabolism: protein synthesis, catabolism. - carbohydrate metabolism (carbohydrate catabolism and anabolism): human= glycolysis, gluconeogenesis, glycogenolysis, glycogenesis, pentose phosphate pathway. Nonhuman= photosynthesis, chemosythesis. - lipid metabolism (lipolysis, lipogenesis): fatty acid metabolism, other: steroids, etc. - amino acid: amino acid synthesis, urea cycle. - nucleotide metabolism: purine metabolism.- other: metal metabolism (iron), ethanol metabolism.

Front 23

Because RBCs lack mitochondria, ATP production happens through

Back 23

Glycolysis?

Front 24

Because RBCs lack mitochondria, ATP production happens through

Back 24

Glycolysis