Biochem Test 4

Front 1

Which of following statements describes a difference between replication of DNA and transcription of RNA?

Back 1

Both strands of DNA are copied in replication, but usually only one is copied in transcription.

Front 2

Which of the following correctly describes a difference between RNA & DNA polymerases?

Back 2

DNA polymerases usually require a primes (i.e., they can only continue a strand, not start one), while most RNA polymerases do not.

Front 3

How do the core enzyme and the holoenzyme of RNA polymerase differ in E. coli?

Back 3

The holoenzyme includes the sigma (alpha) subunit, the core enzyme does not.

Front 4

RNA synthesis begins at the base in the DNA sequence designated by the following number:

Back 4

+1(plus one)

Front 5

Which of the following is not part of the core promoter?

Back 5

the UP element

Front 6

Which of the following offers the best description of a Pribnow box?

Back 6

A promoter consensus sequence located at approximately -10.

Front 7

Which of the following best describes the order of events at the promoter?

Back 7

closed complex --> open complex --> transcription initiation

Front 8

Chain termination occurs, in vivo, when:

Back 8

Either a hairpin loop forms or rho (p) is involved.

Front 9

What is the need for a primer strand in transcription?

Back 9

There is none.

Front 10

Which of the following is the best description of an operon?

Back 10

A group of genes under the control of a common promoter.

Front 11

Which of the conditions would result in the least amount of transcription of the lac operon?

Back 11

glucose lactose

high low

Front 12

RNA transcribed from the coding strand instead of the template strand

Back 12

is called antisense RNA

Front 13

Which of the following RNAs is noted for having a "cloverleaf" structure?

Back 13

tRNA

Front 14

Which end of prokaryotic mRNA are protected from degradation?

Back 14

Neither end

Front 15

Which category of RNA carries amino acids for the process of translation?

Back 15

tRNA

Front 16

The majority of protein synthesis occurs in the

Back 16

cytoplasm

Front 17

Which amino acids have unique codons?

Back 17

trp, met

Front 18

Migration of DNA during electrophoresis is based

Back 18

mostly on the size of the molecule, since the ration of charge to mass is approximately the same, no matter how large the DNA is.

Front 19

Fluorescence and other luminescent methods of visualizing bands offer these advantages over methods dependent on radioactivity.

Back 19

These methods are both more sensitive and require no special license.

Front 20

Enzymes that seal nicks in DNA are called

Back 20

ligases

Front 21

A plasmid is

Back 21

a small circular DNA that is not part of a bacterial chromosome.

Front 22

The following steps are all involved in genetic recombination

1: Screening for cells that contain the recombined gene

2: Cutting the vector with restriction enzyme

3: Mixing the gene of interest with the vector

4: Isolating the gene of interest from its original source

5: Ligating the gene of interest and the vector together.

Back 22

4-->2-->3-->5-->1

Front 23

How is human insulin produced by genetically engineered bacteria?

Back 23

DNA that goes for each of the two polypeptide chains is introduced into two different populations of bacteria.

Front 24

The "c" in cDNA stands for this word:

Back 24

Complementary

Front 25

In the polymerase chain reaction

Back 25

it is possible to amplify small amounts of DNA without cloning.

Front 26

The standard state usually used in biochemistry (deltaGº') includes

Back 26

all concentrations at 1 M, except for [H+], which is 10^-7 M.

Front 27

In general, catabolism

Back 27

is an oxidative process that releases energy

Front 28

Which is the oxidizing agent?

Back 28

NAD+

Front 29

The energy released during metabolism of nutrients can be used to synthesize ATP from ADP and phosphate.

Back 29

True

Front 30

Metabolism takes place in stages

Back 30

and allows for efficient production and use of energy

Front 31

Haworth projection formulas

Back 31

are representations of the cyclic form of sugars; can show the distinction between the alpha and beta anomers

Front 32

In a Fischer projection, which chiral carbon determines whether the sugar is the D- or the L-isomer?

Back 32

highest numbered asymmetric carbon atom

Front 33

Diastereomers are

Back 33

non-mirror-image, non superimposable stereoisomers

Front 34

A pyranose is a sugar that

Back 34

contains a six-membered ring as part of its cyclic structure

Front 35

Which of the following groups is produced when an aldehyde is oxidized?

Back 35

Carboxyl

Front 36

Which of the following best describes the glycosidic bond in the disaccharide shown? (Graph)

Back 36

Alpha(2-4)

Front 37

Glycogen has a similar structure to amylopectin, but is less highly branched.

Back 37

False

Front 38

Plant starch includes amylopectin and cellulose

Back 38

False

Front 39

In humans, pyruvate can be converted to

Back 39

acetyl-CoA and lactate

Front 40

What is the net ATP yield per glucose during glycolysis?

Back 40

2

Front 41

The phosphorylation of fructose 6-phosphate to fructose-1,6-bisphosphate is the committed step in glycolysis because

Back 41

fructose 1,6-bisphosphate can undergo no other reactions than those of glycolysis

Front 42

Which enzyme is the key regulatory enzyme in glycolysis?

Back 42

Phosphofructokinase

Front 43

What kind of enzyme catalyzes the reaction shown?

Back 43

a dehydrogenase

Front 44

How many enzymes of glycolysis are control points for the pathway?

Back 44

3

Front 45

During anaerobic metabolism in red blood cells, the carbons of glucose end up in

Back 45

lactic acid

Front 46

Thiamine pyrophosphate is a coenzyme

Back 46

involved in transfers of two-carbon groups

Front 47

Glycogen is mainly found in

Back 47

liver and muscle

Front 48

The compound uridine diphosphate glucose (UDPG) plays a role in

Back 48

glycogen synthesis

Front 49

Gluconeogenesis differs from glycolysis because

Back 49

the irreversible steps of glycolysis are bypassed

different enzymes are involved

biotin is required for gluconeogenesis and not for glycolysis

All

Front 50

The Cori cycle involves the following

Back 50

Conversion of lactate produced in the muscle by regeneration of glucose in the liver.

Front 51

A chance to be a forensic scientist...... RFLP analysis has been requested

Back 51

The results indicate the accused is innocent

Front 52

Slight differences in a given gene between the two homologous chromosomes are called

Back 52

alleles

Front 53

Which of the following conditions is an example of how genetic engineering is currently used to increase food production?

Back 53

Genetically modified plants have been developed

Genetically modified plants have been

Hormones are given to cows to increase milk

Genetically modified plants have been developed which are resistant to frost

All

Front 54

In DNA sequencing, fragments to be analyzed are produced by

Back 54

selective interruption of DNA synthesis

Front 55

In the conversion of glucose to pyruvate, how many of the actual steps involve electron transfer?

Back 55

1