Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

MCAT Weaknesses > Biological and Biochemical Foundations of Living Systems > Flashcards

Biological and Biochemical Foundations of Living Systems Flashcards

You may prefer our related Brainscape-certified flashcards:
MCAT flashcards
1
Q

What is the body’s physiological response to reduced leptin?

A

A starvation response (increased cortisol, appetite, insulin resistance).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

How are blood calcium levels increased?

A

By stimulating osteoClasts to Catabolize bone, releasing calcium.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

How many molecules of ATP are produced per molecule of glucose by an aerobic organism?

A

36 ATP/glucose.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

How many molecules of ATP are produced per molecule of glucose by an obligate anaerobic organism?

A

2 ATP/glucose.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Water forms a solvation layer around non-polar groups, but what about polar groups?

A

Still forms a solvation layer, but to a lesser extent.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How is the secondary structure of proteins determined?

A

By hydrogen bonding.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

_________ play an important role in the tertiary and quaternary structures of proteins.

A

Hydrophobic interactions.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

A man with type AB blood and a woman with type O blood have children. What blood types might their children inherit?

A

Either type A or type B (think mendelian genetics where A and B are dominant and O is recessive).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What part of an RNA strand gets bound by the repressor when no inducer is present?

A

The repressor binds the operator, preventing transcription.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

How many hydrogen bonds do Adenine and Thymine form with each other? What about Guanines and Cytosines?

A 
AT = 2 H bonds (will denature faster)
GC = 3 H bonds
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Denaturation of DNA is ________ while renaturation is ________.

A

Endothermic. Exothermic.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the centrioles composed of?

A

Microtubules.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Microtubules attach to chromosomes at ______.

A

Centromeres.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the products of the citric acid cycle?

A 
1 GTP
3 NADH
1 FADH₂
2 CO₂
Oxaloacetate
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is the function of sodium-potassium pumps during propagation of an action potential?

A

To pump sodium out of the cell after depolarization. Repolarizes the cell for future action potentials.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

During glycolysis, how many molecules of ATP are produced per molecule of glucose?

A

2 molecules ATP per glucose.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

______ _______ in proliferating ______ cells can lead to cancer.

A

Genetic mutations. Somatic.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Why might host antibodies fail to recognize a bacterial infection in the stomach?

A

Because the antibodies are denatured by the acidic environment and can’t function.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Leukocytes in the body migrate to sites of _________.

A

Inflammation.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is the primary reason for losing water through the skin?

A

To regulate body temperature.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is the function of a lipase?

A

To catalyze the hydrolysis of fats AND other stuff that has a carboxylic acid ester linkage.

22
Q

During bacterial reproduction, what process is associated with the F factor plasmid?

A

Conjugation.

23
Q

If some genes in a bacteria are located apart from the chromosomes, what does this imply?

A

That the separated genes are self-replicating.

24
Q

When vertebrate oocytes undergo meiosis, most of the cytoplasm goes to the ____ while very little goes to the ____ ____.

A

Ovum. Polar bodies (/nurse cells?).

25
Q

Which “replication” process is mRNA (messenger RNA) directly involved in?

A

RNA translation.

26
Q

How do bacteria become resistant to antibiotics?

A

Some bacteria in a population are already resistant. When all their competition is killed off, these flourish. Antibiotics do not “cause” the bacteria to mutate and develop resistance.

27
Q

What process causes norepinephrine to be released into the synapse?

A

An action potential opens calcium channels which floods the synapse with calcium, triggering a series of events which culminate in norepinephrine release.

28
Q

What blood component is not expected to be filtered out by the kidneys?

A

Proteins, which are too big to exit the fenestrated capillaries in the glomerulus.

29
Q

When during mitosis do the tubulin polymers shorten? What event is occurring during this time?

A

During anaphase, when the chromosomes are pulled towards the poles of the cells.

30
Q

Where does calcium bind in the muscle cells to allow muscle contraction?

A

Binds to the troponin complex, allowing tropomyosin to expose the myosin-binding sites on actin.

31
Q

How is blood glucose conserved by the kidney?

A

It gets filtered out in the glomerulus and then reabsorbed in the proximal convoluted tubule.

32
Q

Why might a researcher choose erythrocytes if they wanted to study only plasma membrane proteins?

A

Erythrocytes lack organelles, so when broken down all you get is plasma membrane proteins and not organelle membrane proteins.

33
Q

Which type of bond is formed to link a lengthening glycogen polymer?

A

α-1,4-Glycosidic bonds.

34
Q

Serotonin is released from the neuron via what transport mechanism?

A

Exocytosis.

35
Q

_____ molecules generally have difficulty diffusing across cell membranes.

A

Polar.

36
Q

For a monomeric enzyme, what level of protein structure is the most important for functioning?

A

Tertiary structure.

37
Q

What occurs to sperm mitochondria when they enter the egg? What is the result of this?

A

All sperm mitochondria disintegrate. Therefore, they are not replicated and all future mitochondria come from the mother’s gene line.

38
Q

What is the defining feature of purine structure? What about pyrimidine structure?

A

Purine: double ring
Pyrimidine: single ring.

39
Q

Describe commensalism.

A

One species benefits, the other neither benefits nor suffers.

40
Q

Where do normal gut flora “hang out”? What does this allow them to do?

A

In the cecum, the outpouching of the large intestine (right after the small intestine). This allows them to re-colonize the gut after the gut has been cleansed of bacteria.

41
Q

Which enzyme is responsible for the last step in DNA repair? What does it act alongside?

A

DNA ligase links the new bases back together after the faulty ones are replaced by polymerase.

42
Q

What is the most prevalent protein in the human body?

A

Collagen.

43
Q

What are the 3 stop codons?

A
  1. UAA (U are away)
  2. UGA (U go away)
  3. UAG (U are gone)
44
Q

What is the formula for osmotic pressure?

A

P = iMRT
where P is pressure, i is the # of particles in solution after dissociation, R is the gas constant, T is temp in Kelvin, and M is molarity

45
Q

What are the X steps of glycolysis?

A
  1. Glucose
  2. G6P
  3. F6P
  4. F1,6bP
  5. DHAP and G3P
  6. 1,3 bPG
  7. ATP and 3P
  8. Pyruvate and ATP
46
Q

How many molecules of ATP are produced by glycolysis?

A

4 produced but 2 used, so net +2 ATP.

47
Q

Hemoglobin exhibits what kind of enzyme characteristic?

A

Allosteric effects (cooperativity) whereby the binding of oxygen increases the ability of subsequent oxygen to bind.

48
Q

What differentiates epimers?

A

They differ in structure/orientation at only one carbon (think of a fischer projection).

49
Q

What term is used to describe a signalling cascade in development which changes the structure/function of developing tissues through chemical mediators?

A

Induction. (blah INDUCES blah).

50
Q

At what point do cells in the embryo lose totipotency?

A

Very early on in development when we’re still talking about the “X-cell stages”.

MCAT Weaknesses (3 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions