B/B Incorrects

Question 1

Which of the following best explains why, after several weeks of starvation, acetyl CoA is primarily converted into ketone bodies?

Answer 1

gluconeogenesis depletes the supply of OAA, which is essential for the entry of acetyl coa into the Krebs cycle

Question 2

Which of the following is likely to occur immediately following a meal

Answer 2

inhibition of glucagon secretion (activation of insulin!)

Question 3

RBCs are grown on a nutrient medium containing dinitrophenol, a poison that blocks the electron transport chain. Result on ATP?

Answer 3

remain the same. RBCs don’t have a mitochondria and produce energy anaerobically

Question 4

How to separate aspartic acid and phenylalanine using isolectric focusing?

Answer 4

Asp is an anion and will migrate to the anode. choose a mid pH so they will divide.

Asp (pI 3), Phe (pI6)

Question 5

Which organelle breaks down misfolded proteins?

Answer 5

Lysosome.
They also recycle organelles.

Not
Peroxisomes break down hydrogen peroxide

Question 6

CFTR is active in most epithelial tissues, but not structural tissues such as bone. The form of CFTR gene found in bone cells exhibits:

Answer 6

increased DNA methylation

and thus inactivation

Question 7

Two sick people decided to move to a desert island and start a community that would have a higher freq of individuals that carry the allele for their disorder. This is an example of

Answer 7

founder effect

Not:
bottleneck is the result of a natural disaster

both are extreme specific examples of genetic drift (where allele freq change over generations)

Question 8

A researcher is attempting to use persistent viruses as a vector for gene therapy in insulin resistant diabetics. the new gene will code for a glucose transporter in muscle, connective, and epithelial tissue. Which of the following features of persistent viruses the researcher not likely to modify?

Answer 8

the protein coat recognition marker for tissue type specificity

Question 9

Both immediately before and during exercise, there is increased sympathetic activity. There is a rise in both systolic and diastolic pressure during exercise. Why?

Answer 9

Vasoconstriction of systemic blood vessels, except for those in active muscles

Question 10

An r-selected species of protist uses pseudopia for movement. Which cellular component has the most prominent role in the cleavage and contractility of the cytoplasm during movement?

Answer 10

microfilaments (aka actin)

NOT
microtubules which are imp for cell shape and get walked on

Question 11

amino acid is subjected to electrophoresis at pH 8.5 and observed to migrate to the anode. the isoelectric point of the amino acid is generally:

Answer 11

less than 8.5

Question 12

the nucleoli in the alpha cells will be the largest in a patient with

Answer 12

pancreatic cancer

Question 13

Feline erythrocytes are isolated and all of the RNA is extracted. When the mixture undergoes high-speed centrifugation, for discrete bands at 42, 9s, 18s, and 28s are produced. It must be true that the band at 4S corresponds to

Answer 13

noncoding RNA aka tRNA

Question 14

stenosis is a condition in which the leaves of a heart valve adhere to each other. A patient diagnosed with stenosis in the mitral valve would experience the greatest increase in blood pressure in his:

Answer 14

left atrium

the mitral (bicuspid) valve sits between the left atrium and left ventricle preventing backflow into the atrium

Question 15

A GTPase is activated. What happens?

Answer 15

substrate (eg. glucose) sits, inducing a conformational change

alpha subunit trades GDP > GTP

uses that energy to modify an enzyme or protein (eg. adenylate cyclase)

Question 16

What does adenylate cyclase do?

Answer 16

converts ATP to cyclic AMP (second messenger that activates PKA)

Question 17

Protein Kinase A

Answer 17

Phosphorylates targerts, activating them

Activated by Cyclic AMP

Question 18

Hybridization of a carbonyl?

Answer 18

sp2

Question 19

polar molecules ____ cross the cell membrane

Answer 19

cannot!

Question 20

glycolysis requires

Answer 20

NAD+! We make NADH thanks to GAPDH

Question 21

oxidation of a 2ndary ROH gives you

Answer 21

ketone!

Question 22

Intron 8 of HSP110 most likely contains which of the following

Answer 22

splice acceptor site and 5’ donor site where the spliceosome can bind, form a C complex, create a lariat and catalyze the trans esterification (hydrolysis/condensation) of phosphodiester bond breaking and making

Question 23

HSP110 can bind structurally similar heat shock proteins and functions to facilitate proper protein folding and to reduce levels of nonfunctional protein aggregates. It is which type of protein?

Answer 23

a chaperone

adhesion proteins are integrin and selectin which help cells bind to other cells or the extracellular matrix

Question 24

mature AT1 mRNA is most likely to contain a sequence coding for which genetic factor(s)?

Answer 24

signal sequence (aka localization sequence). something that will tell the synthesized protein where to go

Question 25

poly(A) tail

Answer 25

What you add to the 3’ end of premRNA to protect from degradation outside the nucleus

Question 26

deadenylation

Answer 26

breakdown of the polyA tail

Question 27

meso compound

Answer 27

a compound that has multiple chiral centers
is achiral
has an internal plane of symmetry

Question 28

Where does filtrate have its highest concentration?

Answer 28

medullary collecting duct

Question 29

How will this steroid hormone exert its effects on the cell?

Answer 29

It will diffuse into the cell and produce slow, sustained effects by changing transcription of a gene

Question 30

A certain bacterium was cultured for several generations in medium containing 15N, transferred to medium containing 14N, and allowed to complete two rounds of cell division. Given that the bacterium’s genome mass is 5.4 fg when grown in 14N media and 5.5 fg when grown in 15N medium, individual bacteria with which of the following genome masses would most likely be isolated from this culture?

Answer 30

5.4 fg and 5.45 fg due to semiconservative DNA replication

Question 31

Where is translated protein cleaved?

Answer 31

The endomembrane system. This is posttranslational processing