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Integration Flashcards

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1
Q

Describe the physiological response to a stressor in terms of hypothalamus- pituitary axis

A

1st: alarm–> hypothalamus stimulates pituitary–> pituitary secretes ACTH–> ACTH stimulates adrenal cortex to produce cortisol

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2
Q

Stages of cognitive appraisal

A

1st: initial evaluation of the environment and associated threat
2nd: if and only if primary appraisal reveals a threat–> can I deal with this stress?

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3
Q

Schachter-Singer Theory of Emotion

A

“I am excited because my heart is racing and everyone else is happy”

  • 1st: cognitive appraisal and nervous system arousal
    2nd: Conscious emotion
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4
Q

Cannon-Bard Theory of Emotion

A

“I am afraid because I see a snake and my heart is racing… Let me out of here”

  • 1st response: nervous system arousal and conscious emotion
    2nd: Action
  • *emotional responses are independent responses
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5
Q

James-Lange Theory of Emotion

A

“I must be angry because my skin is hot and my blood pressure is high”

1st: nervous system arousal
2nd: conscious emotion

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6
Q

opponent process theory

A

when a drug is taken repeatedly the body will attempt to counteract the effects of the drug by changing physiology
- cocaine withdrawal would lead to depressed mood, fatigue, decreased heart rate…

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7
Q

From bottom up, state Maslow’s hierarchy of needs

A

Bottom: physiological

  • safety
  • Love/belonging
  • esteem
  • self-actualization
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8
Q

Yerkes-Dodson Law

A

best performance occurs at moderate arousal
Further application: Yerkes-Dodson law of social facilitation states that being in presence of others will greatly increase our ability to perform simple tasks, but we will suck at complex tasks

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9
Q

The notable exceptions to the electron filling orbital

A

has to be transition elements:

Cu and Cr

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10
Q

charge of electron

A

-1.6 * 10^-19 C

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11
Q

Describe UTP

A
  • Uridine 5’-triphosphate
  • ribose and pyrimidine base
  • Its main role is as substrate for the synthesis of RNA during transcription.
  • Metabolism: UDP-glucose enters the synthesis of glycogen. UTP is used in the metabolism of galactose, where the activated form UDP-galactose is converted to UDP-glucose. UDP-glucuronate is used to conjugate bilirubin to a more water-soluble bilirubin diglucuronide.
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12
Q

When UDP-glucose reacts with the non-reducing end of a lengthening glycogen polymer, what type of bond is most commonly formed?

A

alpha-1,4- Glycosidic bond

This is the bond that links most glucosyl moieties in glycogen

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13
Q

Describe the process of action potential induced muscle contraction

A
  • AP depolarized the T-tubule
  • SR releases Ca2+
  • Ca2+ binds troponin
  • tropomyosin exposes myosin-binding site on actin
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14
Q

Paclitaxel stabilizes tubulin polymers once they are formed. What phase of mitosis is likely to be hampered by this? (hint: what process depends on shortening of tubulin)

A

-Anaphase: anaphase is when the chromosomes are pulled towards opposite poles of the cell

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15
Q

The GTP used by tubulin could come directly from the products of:
glycolysis, pentose phosphate pathway, citric acid cycle?

A

The citric acid cycle directly produces GTP

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16
Q

Citric Acid Cycle

A

-In eukaryotic cells, the citric acid cycle occurs in the matrix of the mitochondrion
-Net Results Pyruvate Dehydrogenase Complex and Citric Acid Cycle:
4 NADH; 1 FADH2; 1 GTP
12.5 ATP per pyruvate= 25 ATP per glucose
Regulated by: whenever ATP levels rise, phosphorylating PDH inhibits acetyl CoA production. The Complex is activated by rising levels of ADP and pyruvate dehydrogenase phosphatase
-Rate limiting enzyme: isocitrate dehydrogenase

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17
Q

What derives from the neural crest?

A

neurons and glial cells of sensory, sympathetic, and parasympathetic nervous system

  • medulla cells of adrenal gland
  • pigment cells of epidermis
  • cranial facial components
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18
Q

As non-polar protein groups clusters in water, the water experiences a ____ in entropy?

A

INCREASE. This increase in entropy is the predominant thermodynamic influence resulting in clustering of nonpolar groups in polar solvents

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19
Q

What information is needed to calculate the number of moles of H2CO3 in a sample of rainwater by titrating it with .05 M NaOH??

A

Volume of NaOH used to reach endpoint

- the volume of acid is only needed if we want to find the [ ] of starting material once we found initial moles

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20
Q

enantiomers have ___ physical properties except for _____

A

same, except for direction of polarization for plane polarized light.
** Remember that enzymes are stereospecific

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21
Q

Name the pyrimidines in DNA

A

Thymine, Cytosine

** one carbon-nitrogen ring bases

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22
Q

Name the purines

A

-the 2 carbon nitrogen ring bases
- adenine and guanine
“Pure As Gold”

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23
Q

What pH range for an indicator is best for titration of stomach acid with NaOH?

A

-the titration of a strong acid with a strong base has an equivalence point at 7!!! so any indicator around 7

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24
Q

oxidation number of N

A

-3

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25
Q

if a reaction proceeds spontaneously to the right then Keq must be

A

greater than 1

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26
Q

knowing that a reaction is of 2nd order, we know that

A
  • consists of interactions between 2 molecules
  • 1/ [A] vs time is a straight line
  • rate= k[A]^2
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27
Q

What type of lens would best fix hyperopia (farsightedness)?

A

a convex lens would be best because it would be converging the light

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28
Q

In people with myopia (nearsightedness) the image of the object is focused within the vitreous humor before it reaches the retina. Why does this happen? (consider the ciliary muscle)

A
  • the focal length of the crystalline lens is adjusted by tensing and relaxing the ciliary muscle.
  • people with myopia have a shortened focal length due to the ciliary muscle not being able to relax
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29
Q

Why is atomic oxygen so reactive and rare?

A

it is a free radical: 6 valence electrons

-2 in -1; 1 in 0; 1 in +1

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30
Q

Define effective nuclear charge

A

the net positive charge experienced by valence electrons

-increases to the right and UP

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31
Q

Glycine- how could we possibly test a sample to see if it contains mostly glyceine???

A

not optically active so we can use polarized light to see if sample is optically active

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32
Q

When placed in an electric field, what compound will migrate towards the cathode at pH 7?

A. H2NCH2COOH
B. H2NCH2CHNH2COOH

A

only molecules with an overall positive charge will migrate to cathode!

-at acidic or neutral conditions, -NH2 is protonated!!!! SO B

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33
Q

define mutarotation

A

the phenomenon that occurs with monosacharides around the 1st carbon (anomeric carbon)
-opening and closing results in the formation of anomers in solution

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34
Q

define hemiketal

A
  • derived from ketones
  • formed by addition of an alcohol to it
  • will have an -OR and -OH group
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35
Q

how to determine alpha or Beta linkages?

How is Sucrose connected/ named?

A

You want to compare the anomeric OH with the last CH2OH to determine alpha beta configs

  • alpha means different; beta means same
  • a-D-glucopyranosyl-B-Dfructofuranoside
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36
Q

which form of glucose can be oxidized, linear or hemiacetal?

A

only linear glucose can be oxidized

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37
Q

what compounds have higher Rf values, polar or nonpolar?

A

Non-polar compounds move up the plate most rapidly (higher Rf value)
-Non-polar compounds move up the plate most rapidly (higher Rf
value), whereas polar substances
travel up the TLC plate slowly or not at all (lower Rf
value).

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38
Q

How is blood pH rapidly changed?

A

via changes in respiration

-increased respiration will increase blood pH; reduced respiration will decrease blood pH

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39
Q

A scientist wished to to test the various effects of solutes on osmotic pressure. She has two chambers filled with distilled water separated by semipermeable membrane. Which of following solutes will cause greatest change in osmotic pressure??

  • NaCl
  • HCOC-
  • CaCl2
  • glucose
A
  • osmotic pressure is a colligative property determined by number of particles present (not the identity of the particles).
  • CaCl2 is the answer because it will simply dissolve into more parts
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40
Q

MSG can be isolated via fermentation of corn or sugar cane and is used as food additive. Bacterial production of MSG must be:
anaerobic or aerobic and occur after which metabolic pathway?

A

anaerobic and occur after glycolysis

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41
Q

define nondisjunction

A

There are three forms of nondisjunction: failure of a pair of homologous chromosomes to separate in meiosis I, failure of sister chromatids to separate during meiosis II, and failure of sister chromatids to separate during mitosis. Nondisjunction results in daughter cells with abnormal chromosome numbers (aneuploidy).

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42
Q

maternal lineage can be traced by sequencing the mitochondrial DNA because the mitochondrial genome is derived primarily from the mother. Explain this

A

following penetration, the sperm derived mitochondria disintegrate within the egg

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43
Q

where do the normal gut flora hangout?

A

cecum (large intestine)

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44
Q

facultative anaerobe

A

is an organism that makes ATP by aerobic respiration if oxygen is present, but is capable of switching to fermentation

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45
Q

During replication repair, enzymes can reverse an error that would lead to the formation of an oncogene from a proto-oncogene. What enzyme is involved in the last step of DNA repair??

A

DNA ligase:
During base repair, a base is exercised by a restriction enzyme, replaced by DNA polymerase and linked to the bases around in by DNA ligase

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46
Q

give the formula for osmotic pressure

A 
π = iMRT
i= number of particles in solution per original formula unit
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47
Q

what would an increase in citrate due to levels of pyruvate formation??

A

an increase in citrate would decrease pyruvate formation

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48
Q

define induction in development

A
  • ability of one group of cells to influence the fate of other nearby cells
  • a signaling cascade in development that changes the structure or function of developing tissues via chemical mediators
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49
Q

what affects the frequency of sound waves travelling through air, as measured by the detector?

A

the speed of the source of sound

** distance and surface area of detector only affect intensity

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50
Q

When light passes from one medium to another what changes? What stays constant?

A

velocity and wavelength change.

** frequency stays constant

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51
Q

When sounds passes from one medium to another what properties of the wave change?

A

-wavelength and speed!!!

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52
Q

right the equation that relates free energy to Keq

A

deltaG= -RT lnKeq

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53
Q

define normality

A

(equivalents) of solute per liter of solution.

** will equal M in monoprotic acids

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54
Q

during cold weather adaptation processes, the cells of animals would change how?

A
  • to maintain membrane fluidity in the cold, more unsaturated fatty acids would be added!!!
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55
Q

describe Norepinephrine

A
  • amino acid-derivative hormone
  • fast onset
  • bind G protein-coupled receptors
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56
Q

Thyroxine and triiodothyronine

A
  • amino acod-derivative hormones
  • slower onest, but longer duration
  • function: regulate metabolic rate
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57
Q

Tropic Hormones released by hypothalamus

A

GnRH–> stimulates FSH and LH
GHRH –> stimulates growth hormone

  • TRH –> stimulates thryroid-stimulating hormone (TSH)
  • CRF–> ACTH
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58
Q

ANP

A

atrial natriuretic peptide

  • regulates salt and water balance
  • when cells in atria are stretched from increased blood volume, they release ANP which promotes excretion of Na+. Think of it as functionally antagonistic to aldosterone
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59
Q

ventilation is regulated by the neurons in the

A

medulla oblongata: they contain chemoreceptors that are sensitive to carbon dioxide

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60
Q

emphysema

A

-characterized by destruction of alveolar walls; results in decreased elastic recoil of the lungs

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61
Q

what cells produce pepsinogen?

A

chief cells of the stomach produce pepsinogen which is activated by HCl to pepsin.
- pepsin cleaves peptide bonds near aromatic amino acids

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62
Q

what 6 products does the stomach produce?

A

HCl, pepsinogen, mucus, bicarbonate, water, intrinsic factor

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63
Q

enteropeptidase is secreted by what and has what function?

A

secreted by: duodenum

Function: activates digestive enzymes of accessory organs like trypsin and procarboxypeptidases A and B

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64
Q

Liver

A
  • located upper right quadrant of abdomen
  • bile produced in liver –> bile ducts –> stored in gallbladder
  • received blood draining from abdominal portion of digestive tract through hepatic portal vein– nutrient rich blood is then processed by the liver before entering inf. vena cava
  • detoxifies exogenous and endogenous products: modifies ammonia to urea
  • syntheses: albumin and clotting factors
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65
Q

what activates gallbladder to contract and release bile?

A

CCK

66
Q

Summarize the digestion of Triacylglycerols

A

Mouth–> lipase
pancrease–> lipase
Gall Bladder–> Bile miscelles
metabolized to 2-Monoacylglycerols Fatty Acids

67
Q

Summarize Digestion of Carbohydrates

A

Mouth–> amylase
Pancreas–> amylase
Small Intestine (Brush border)–> sucrase, lactase, maltase, isomaltase
digested to: glucose, galactose, fructose

68
Q

Summarize Digestion of Proteins

A

Stomach–> Pepsin
Pancreas–> Trypsin, chymotrypsin, carboxypeptidases, A and B
Small intestine (brush border): Dipeptidases, aminopeptidases
Digested to: Amino Acids

69
Q

Name the different stages of the cell cycle

A

G1: Presynthetic Gap
S: Synthesis of DNA
G2: Postsynthetic GAP
M: Mitosis

70
Q

What occurs in G1 of the cell cycle

A
  • cells make organelles for energy and protein production and increase in size
  • have to pass through a restriction zone to get to S stage
71
Q

S Stage of cell Cycle

A
  • the cell replicates its genetic material so each daughter will have identical properties
  • after replication.. each chromosome has 2 identical chromatids that are bound at the centromere
  • *still only 46 chromosomes, even though 92 chromatids are present
72
Q

G2 Stage

A

-cell passes through another checkpoint

-

73
Q

M Stage of Cell cycle

A

Mitosis and cytokinesis

74
Q

Stages of Mitosis

A

Prophase, Metaphase, Anaphase, Telophase

75
Q

Prophase of Mitosis

A
  • chromosomes condense, spindle forms
  • centriole pairs separate and move to opposite poles of cell
  • spindle fibers are made of microtubules
  • nuclear membrane dissolves
  • kinetochores appear at centromere
76
Q

Metaphase of Mitosis

A
  • centriole pairs are at opposite ends of cell

- the kinetochore fibers interact with the fibers of the spindle apparatusto align chromosomes at metaphase plate

77
Q

Anaphase of Mitosis

A
  • sister chromatids separate

- sister chromatids pulled towards opposite poles of the cell by shortening of kinetochore fibers

78
Q

Telophase

A
  • new nuclear membrane forms

- chromosomes uncoil

79
Q

nucleolus

A

-where ribosomal RNA is synthesized

80
Q

Prophase 1 (Meiosis 1)

A
  • -chromatin condenses

- major difference from mitosis; homologous chromosomes come together as tetrads during synapsis; crossing over occurs

81
Q

Metaphase 1 (meiosis 1)

A
  • tetrads align at the metaphase plate
  • differences from mitosis: homologous chromosomes line up on opposite sides of metaphase plate as opposed to individual chromosomes lining up on metaphase plate
82
Q

Anaphase 1 (meiosis 1)

A
  • homologous pairs separate and are pulled to opposite sides of cell
  • disjunction: each chromosome of paternal origin separates from its homologue of maternal origin
  • either chromosome can end up on either side of cell resulting in random segregation
83
Q

Telophase 1 (meiosis 1)

A
  • nuclear membrane forms around each new nucleus

- each cell is now haploid (23)

84
Q

What is end result of Meiosis?

A

-up to 4 haploid daughter cells have formed

85
Q

define epimers

A

sugars that only differ around 1 carbon center

ex. D-glucose and D-galactose

86
Q

NADPH is an important reducing agent produced by the …

A

pentose phosphate pathway

87
Q

Maltose is a disaccharide made from

A

glucose and glucose

88
Q

The region between 1760 and 1665 cm-1 in infrared spectroscopy is indicative of what??

A

carbonyl stretch

89
Q

mutarotation

A
  • is the change in the optical rotation because of the change in the equilibrium between two anomers, when the corresponding stereocenters interconvert. Cyclic sugars show mutarotation as α and β anomeric forms interconvert.
  • process by which we get a racemic mixture of anomers in aqueous solutions
90
Q

intercalated discs

A

the organization of multiple miscle cells connected via gap junctions which allows rapid and coordinated contraction

91
Q

what filament is associated with troponin and tropomyosin?

A

actin
Mneumonuc: acTin (t)
acthin–> actin has the thin fillaments

92
Q

which zone of the sarcomere remains constant during contraction?

A

A band

93
Q

name the parts of the sarcomere

A

z- the end of the alphabet and end of the sarcomere
M- Middle of the myosin filament
I- thin letter (thin filaments only)
H- thick letter (thick filaments only)
A- All of the thick filament, whether or not it is overlapping

94
Q

concerning the sliding filament theory, ATP is needed for what purpose?

A
  • the binding of ATP is required for releasing the myosin head from the actin filament
  • **it is the disassociation of ADP and Pi from myosin that is responsible for the powerstroke, NOT hydrolyissi of ATP
95
Q

true or false, the hydrolysis of ATP is the drive for the powerstroke?

A

false; the dissociation of ADP and Pi from myosin is responsible for the powerstroke

96
Q

what causes the disease tetanus?

A

source: bacteria called Clostridium tetani

MOA: the toxin tetanospasmin blocks the release of GABA from neurons that inhibit motor neurons which leads to constant contraction

97
Q

name the 2 energy stores of muscle

A
  1. creatine phosphate

2. myoglobin (has O2 stores) to keep oxidative phosphorylation going

98
Q

what is bone derived from?

A

bone is connective tissue derived from embryonic mesoderm

99
Q

DNA ligase

A

is a specific type of enzyme, a ligase, (EC 6.5.1.1) that facilitates the joining of DNA strands together by catalyzing the formation of a phosphodiester bond.
-Biologically, DNA ligases are essential for the joining of Okazaki fragments during replication, and for completing short-patch DNA synthesis occurring in DNA repair process.

100
Q

parathyroid hormone

A

-promotes bone resorption to increase blood levels of Ca

101
Q

penetrance

A

the proportion of the population with a given genotype who actually express the phenotype

102
Q

expressivity

A

the different manifestations of the same genotype across a population. Its examined at the individual level though

103
Q

Name the 3 ways bacteria increase genetic variability

A
  • transformation:
  • conjugation
  • transduction
104
Q

bacterial transformation

A

acquisition of genetic material from environment that can be integrated into bacterial genome

105
Q

bacterial conjugation

A

transfer of genetic material from one bacterium to another across a conjugation bridge

106
Q

transduction

A

transfer of genetic material from one bacterium to another using a bacteriophage as a vector

107
Q

crossing two heterozygotes for a trait with complete dominance results in

A

1: 2:1 ratio of genotypes

- 3:1 ratio of phenotypes

108
Q

crossing two heterozygotes for both traits in a dihybrid cross results in

A

9:3:3:1 phenotype

109
Q

Which glycolytic reaction cannot be directly reversed in gluconeogenesis?
1,3-bisphosphoglycerate → 3-phosphoglycerate
Glucose → glucose-6-phosphate
Glucose-6-phosphate → fructose-6-phosphate
Glyceraldehyde 3-phosphate → 1,3-bisphosphoglycerate

A

Glucose → glucose-6-phosphate

110
Q

The three most favorable steps of glycolysis are:

A

glucose→ G-6-P, fructose-6-phosphate→ fructose 1,6-bisphosphate, and phosphoenolpyruvate→ pyruvate.

111
Q

amphoteric refers to

A

compounds that can act as an acid or a base

112
Q

amphipathic

A
  • amphiphilic

- Detergents are amphipathic (or amphiphilic) molecules because they are both hydrophilic and hydrophobic

113
Q

Patients suffering from Guillain-Barre syndrome, a demyelinating illness of the peripheral nerves, often need to be artificially ventilated until they recover. What is the most likely explanation for why these patients have difficulty breathing?

A
  • The speed of nerve conduction to muscle is decreased. Correct Answer
    • Myelination speeds up nerve conduction by allowing action potentials to “skip over” myelinated regions of the neuron; these action potentials are instead transmitted between the nodes of Ranvier on the axon. Demyelination due to illness slows nerve conduction enough that a patient would have difficulty contracting the diaphragm (choice C is correct).
114
Q

-where are the main chemoreceptors for respiration located?

A

-the main respiratory drive comes from CO2-sensitive chemoreceptors within the medulla.

115
Q

Addition of reactants to an equilibrated system will result in a change of which of the following?

A. 	Keq
B. 	ΔG°’ 
C. 	ΔG 
D. 	The rate constant k
A

–C. delta G
Addition of a reactant (or a product) would change the ΔG for that reaction (choice C is correct). The remaining three kinetic and thermodynamic constants do not vary with reagent concentration. The relationship between ΔG°’ and ΔG is described by the equation ΔG = ΔG°’ + RT ln Q. Given that Q changes with reagent concentration, ΔG must also change. As ΔG°’ specifies a specific set of reagent concentrations, temperature, and pressure.

116
Q

relate delta G with delta G’not

A

ΔG = ΔG°’ + RT ln Q

117
Q

what is the effect of constriction of the efferent arteriole of the nephron

A

Increased GFR, resulting in increased sodium excretion
WHy? Constriction of the efferent arteriole will restrict the flow of blood out of the glomerulus and result in increased pressure within the glomerulus. This would increase GFR (choices B and D can be eliminated). An increase in GFR would result in more filtrate passing through the nephron, and increased loss of sodium

118
Q

Which of the following viruses does NOT have an immediately infective genome?

A. 	An enveloped (+)RNA virus
B. 	A naked (+)RNA phage
C. 	A retrovirus 
D. 	A (–)RNA virus
A

D. A (–)RNA virus Correct Answer
WHy?:
All (+)RNA viruses have infective genomes because the genome acts like mRNA and can be immediately translated to produce viral proteins (choices A and B can be eliminated). A retrovirus is a type of (+)RNA virus that undergoes the lysogenic cycle (choice C can be eliminated). In contrast, (–)RNA viral genomes are not immediately infective. The (–)RNA must be converted to (+)RNA by an RNA-dependent RNA polymerase (this enzyme must be carried by the virus and encoded in the viral genome) to generate mRNA that can be translated to make viral proteins. If the genome (and only the genome) of a (–)RNA virus enters a cell or is combined with active host cell extracts, nothing will happen. If RNA-dependent RNA polymerase is added, the genome will then be infective and viral progeny will form (choice D is not immediately infective and is the correct answer choice).

119
Q

In cellular respiration, which step causes the difference in ATP yield occur between prokaryotes and eukaryotes and by how many ATP?

A
  • The difference occurs in the electron transport chain and is 2 ATP. Correct Answer
    -WHy:
    The difference in ATP yield between prokaryotes and eukaryotes is 2, with prokaryotes producing 32 ATP and eukaryotes producing 30 ATP (choices C and D are wrong). In prokaryotes, the 2 NADH produced in glycolysis have direct access to the cell membrane where the electron transport chain occurs. However in eukaryotes, the electrons from glycolytic NADH must be transported into the mitochondria before they can enter the electron transport chain; furthermore they do not begin their interaction with the ETC until its second protein (coenzyme Q, choice A is wrong and choice B is correct). Glycolysis has the same output in both prokaryotes and eukaryotes.
120
Q

α-Helices and β-sheets are part of a protein’s:

A

secondary structure and arise from hydrogen-bonding interactions.

121
Q

Michaelis-Menten Equations

A
  • describes how the rate of the reaction depends on the concentration of the enzyme and the substrate
  • v= (vmax * [S] ) / (Km + [S] )
122
Q

Lineweaver-Burk Plots

A
  • x-intercept = -1/Km
  • y-intercept= 1/ Vmax

**useful in determining what type of inhibition is at play

123
Q

Competitive Inhibition

A
  • involves occupancy of active site
  • vmax is NOT affected
  • it DOES increase Km
124
Q

Noncompetitive inhibitor

A

non–> allosteric

  • bind to allosteric site instead of active site which induces a change in enzyme conformation
  • they bind equally well to enzyme and enzyme substrate complex
  • *it decreases vmax
    • DOES NOT affect Km
125
Q

Mixed-Inhibition

A
  • when an inhibitor can bind to enzyme or enzyme-substrate complex, but has different affinity for each
  • binds at allosteric site
  • on Lineweaver-Burk plot, the curves for the activity with and without the inhibitor intersect at a point that is not on either axis
  • *decreases vmax
126
Q

Uncompetitive Inhibition

A
  • bind ONLY to the enzyme substrate complex
  • locks the substrate in the enzyme
  • binds at allosteric site
  • lowers Km and Vmax
  • lineweaver-burk plots are parallel
127
Q

Pentose Phosphate Pathway

A
  • occurs in cytoplasm
  • produces NADPH and ribose 5-phosphate
  • oxidative phase is irreversible, produces 2 NADPH, and has rate limiting enzyme G6PD
  • non-oxidative phase: glycolytic intermediates like fructose 6-phosphate and glyceraldehyde 3-phosphate can feed into the pentose but also vice versa
128
Q

products of the citric acid cycle

A
  • 1 GTP
  • 3 NADH
  • 1 FADH2
  • 2 CO2
  • Regenerated oxaloacetate
129
Q

Is it possible to convert acetyl CoA to pyruvate?

A

No.

pyruvate –(pyruvate dehydrogenase)–> acetyl CoA is an irreversible step

130
Q

what do we get from each molecule of pyruvate?

A

4 NADH
1 ATP
1 FADH
** remember we get 2 molecules of pyruvate from 1 molecule of glucose

131
Q

WHAT inhibits pyruvate dehydrogenase?

A
  • Acetyl CoA
  • NADH
  • ATP
  • Fatty Acids
132
Q 
It has been shown that hydroxylation of proline in the presence of ascorbic acid dramatically increases the stability of the procollagen superstructure that comprises collagen. Which of the following likely contributes most to the added stability that results from hydroxylation?
  A. 	Increased hydrogen bonding 
    B. 	Stereoelectronic effects 
    C. 	Van der Waals forces
    D. 	Steric effects
A

B. Hydroxylation of the proline functional group effectively produces an induced dipole in which the electronegative oxygen of the hydroxyl group makes the charge of the adjacent hydrogen and carbon atoms δ+; stereoelectronic effects in the form of “stacked” δ- and δ+ charges from the three inter-woven alpha helices in close proximity to one another creates a highly stable triple helix quaternary structure (answer choice B is correct).

133
Q

An individual action potential in a model neuron results in 100 sodium ions crossing the cell membrane. Given that the sodium-potassium pump requires a single molecule of ATP per cycle, how many acetyl-CoA would be required to generate enough energy to extrude the new sodium in the cell via the pump?

A. 	1 
B. 	4 
C. 	5
D. 	50
A

B. Each acetyl-CoA generates 10 ATP equivalents (3 NADH = 7.5 ATP, 1 FADH2 = 1.5 ATP, and 1 GTP = 1 ATP) and the sodium-potassium pump removes three sodium from the cell per cycle at the expense of one ATP. A total of 34 cycles of the pump would be required to remove the 100 sodium from the cell and this would require 34 ATP. To ensure we have sufficient ATP, four acetyl-CoA are needed (choice B is correct).

134
Q

Which of the following figures best represents the epithelial cell most affected by celiac disease? (Hint:The passage states that celiac disease affects the villi of the small intestine)

A

The small intestine is lined with columnar epithelial cells, which are characterized by being tall in shape (choices A and D can be eliminated). The columnar epithelial cells in the small intestine have microvilli to increase their surface area, not cilia (choice C is correct and choice B is wrong).

135
Q

What best explains why a cold sore breaks out even though the virus herpes complex normally lies dormant?
A. After host cell lysis, the host can immediately recognize the virus via antibodies and subsequently removes HSV-I infection from the body; cold sores are just a side effect of this action.
B. After budding, the virus envelopes itself in the cell membrane of the host; this decreases host recognition of HSV-I, increases the length of time the virus can spread, and leads to a breakout of cold sores. Correct Answer
C. After host cell lysis, the host cannot immediately recognize the virus itself and HSV-I goes on to infect other cells, causing a breakout of herpes cold sores around the mouth. Your Answer
D. After the virus is activated, it causes the host cell to release large amounts of hormones; this sudden regional hormone imbalance causes cold sores.

A

B. HSV-I is able to lie dormant in host cells, so it must undergo the lysogenic cycle. The question stem also says that the virus enters the productive cycle when it is activated, meaning the new viral particles bud out of the host cell instead of lysing the host cell (choice A and C discuss host cell lysis and can be eliminated). When the virus buds out of the host cell, it acquires an envelope that is derived from the host cell plasma membrane. As a consequence, the host immune system can recognize the virus as “self” instead of “foreign,” and therefore may not immediately attack it (choice B is correct). While a sudden hormone imbalance might trigger activation of HSV-I, cold sores are not caused by sudden regional hormone imbalance as a direct result of virus activation (choice D is wrong).

136
Q

Multiple sclerosis (MS) is an autoimmune disease that results in demyelination of central nervous system axons. Which of the following could change as a result of this condition?

I Perception of sensory stimuli
II. Temporal summation in a postsynaptic neuron
III. The strength of an action potential in a demyelinated axon

A

C. Items I and II are true: Demyelination of an axon can result in slowed or lost conduction of action potentials, which could affect all types of stimuli perceived by the nervous system (choice B can be eliminated). Specifically, this affects the timing of neurotransmitter release by the neuron, which then changes the frequency of EPSPs or IPSPs in the postsynaptic cell (choice A can be eliminated).

137
Q

A couple is told by their doctor that the reason why they cannot have children is that the sperm of the male lack motility because it does not have the structures responsible for propulsion. Which cellular structures are likely to be the underlying cause of this lack of motility?

A

Microtubules form the flagella that give mobility to the sperm.

138
Q

Malformation of which cytoskeletal structures may be linked to an inability to contract muscle?

A

Microfilaments are used for movement and contain the actin filaments used in muscle contraction.

139
Q

Attitudes show flexibity over time unlike personality

A

TRUE

140
Q

Western blot

A

detects specific AA sequence in proteins

141
Q

what derives from mesodermal tissue

A

heart, muscles, skeletal system

142
Q

what derives from the ectoderm?

A
  • lens of the eye
  • mammary glands
  • epidermis, hair, and nails
  • nervous system and adrenal medulla
  • inner ear
143
Q

what derives from the endoderm?

A

epithelial lining of digestive and respiratory tracts

  • parts of the liver
  • pancreas
  • thyroid and bladder
  • distal urinary and reproductive tracts
144
Q

Generating ATP requires

A

unequal contribution of gene products from maternal and paternal DNA

145
Q

where does our mitochondrial DNA come from?

A

maternal descent

146
Q

during DNA testing, often only one locus is investigated. WHat is a locus?

A

-the place on the chromosome where alleles for a gene reside

147
Q

Humanistic perspective

A

free will is the foremost determinant factor in behavior

148
Q

demographic transition

A

a period in which a society with high birth rate and high death rate see both rates drop due to improvements in healthcare and health education

149
Q

The STrecker synthesis produces

A

amino acids

150
Q

in reduced light what photopigment is most important?

A

rods are more functional so rhodopsin is more important

151
Q

Rods

A

rods have low sensitivity to detail

  • not involved in color vision
  • permit night vision
152
Q

cones

A
  • color vision

- fine details

153
Q

Superior colliculus

A

controls saccadic eye movements

154
Q

inferior colliculus

A

processes auditory input

155
Q

reactive social movement

A

resists social change

156
Q

consensus cues

A

relate the extent to which a person’s behaviors differs from others

157
Q

If a person’s behavior deviates from socially acceptable behavior

A

we will form a dispositional attribution about the person’s behavior (internal)

158
Q

symbolic interactionism

A

interactions with others and their opinions influences how a person perceives himself

159
Q

interferon

A

interfere with viral replication

160
Q

the 3 stop codons

A

UAA, UGA, UAG

MCAT integrated (3 decks)

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