B/B Review Flashcards
1
Q
When the heart muscle contracts, pushing blood out
A
systole
2
Q
Enzymes that catalyze the breakdown of proteins into smaller polypeptides or single amino acids
A
protease
3
Q
ssDNA is held together by what type of bond?
A
phosphodiester bonds
4
Q
How is ssDNA denatured?
A
When the nucleases break apart their phosphodiester bonds that hold the individual nucleotides
note: Slight increases in heat would NOT break apart these bonds. They would for hydrogen bonds in dsDNA though
5
Q
DNA renaturation involves the formation of base pairs. This is an [exothermic/endothermic] process
A
exothermic process
heat is released
forming bonds is ALWAYS exothermic
6
Q
Bond breaking is an [endothermic/exothermic] process
A
endothermic process
because it REQUIRES energy
7
Q
adds nucleotides to growing DNA chains and participates in DNA replication
A
DNA polymerase
8
Q
True or False
Proteins lose 3D shape when they’re denatured, but not their amino acid (primary) formation
A
True
this breaks the hydrogen bonds
9
Q
myelinating cells of the central nervous system (CNS)
A
oligondendrocyte
10
Q
Signals from neurons that have myelin degredation would disspiate [faster/slower] than healthy neurons
A
faster
11
Q
genetic regulatory system found in bacteria and their viruses in which genes coding for functionally related proteins are clustered along the DNA
A
operon
12
Q
a region of DNA upstream of a gene where relevant proteins (such as RNA polymerase and transcription factors) bind to initiate transcription of that gene
A
promoter
13
Q
a gene involved in controlling the expression of one or more other genes
A
regulator gene
14
Q
genes that code for proteins and RNAs except regulatory factors
A
structural genes
15
Q
a series of three genes in bacteria that produce the necessary enzymes to obtain energy from lactose.
A
lac operon
16
Q
organic compounds without a benzene ring
A
aliphatic compounds
17
Q
catalyse the transfer of phosphate groups from ATP molecules to a specific substate.
A
kinase
18
Q
catalyze the decomposition of ATP into ADP and a free phosphate ion.
A
ATPase
19
Q
use water molecules to dephosphorylate a substrate
A
phosphatase
20
Q
Presence of the Effector
enables transcription
A
inducible regulation
21
Q
Presence of the Effector
blocks transcription
A
repressible regulation
22
Q
The Repressor binds
to the Operator
to block transcription
A
Negative Regulation
23
Q
The Activator binds
to the Operator
to enable transcription
A
Positive Regulation
24
Q
True or False
Cellular components like lymphocytes, antibodies, proteins, etc are a lot larger than ions and glucose. Unless otherwise stated, don’t assume they can diffuse through membranes
A
true
25
# True or false
a single mutation event is almost always more likely than multiple events
True
26
having only one sex chromosome
monosomy
## Footnote
Monosomy's are usually unviable; they tend to result in a plethora of health problems that cause infantile death
27
# True or False
Multiple mutation events are just as likely as a single mutation event
**False**. A single mutation event is almost always more likely than multiple events
28
Paternal nondisjunction conferring two copies of a gene would result in what genetic condition?
trisomy
## Footnote
two copies from the father, and one from the mother
29
the failure of one or more pairs of homologous chromosomes or sister chromatids to separate normally during nuclear division, usually resulting in an abnormal distribution of chromosomes in the daughter nuclei
nondisjunction
30
another name for amino acids.
Monomeric proteins
31
the fatty acid chains of triglycerides contain ____ fatty acids
the fatty acid chains of triglycerides contain **18** fatty acids
32
glycogen breaksdown into glucose-1-phosphate and glucose
glycogenolysis
33
An increase in glycogenolysis would lead to a [increase/decrease] in glycogen levels
An increase in glycogenolysis would lead to a **decrease** in glycogen levels
34
used as an energy source during the elongation and translocation steps of translation
GTP
35
increases the MW of a molecule (because it is becoming a macromolecule of repeating segments)
oligomerization
36
First step in gene expression. It involves copying a gene's DNA sequence to make an RNA molecule.
transcription
## Footnote
[KA article](https://www.khanacademy.org/science/ap-biology/gene-expression-and-regulation/transcription-and-rna-processing/a/overview-of-transcription)
37
mRNA is "decoded" to build a protein (or a chunk/subunit of a protein) that contains a specific series of amino acids.
## Footnote
[KA article](https://www.khanacademy.org/science/ap-biology/gene-expression-and-regulation/translation/a/translation-overview)
translation
38
The three steps of translation (in order) are...
1. initiation
2. elongation
3. termination
## Footnote
[KA article](https://www.khanacademy.org/science/biology/gene-expression-central-dogma/translation-polypeptides/a/the-stages-of-translation)
39
in this stage of translation, the ribosome gets together with the mRNA and the first tRNA so translation can begin.
initiation
40
in this stage of translation, amino acids are brought to the ribosome by tRNAs and linked together to form a chain.
elongation
41
in the stage of translation, the finished polypeptide is released to go and do its job in the cell.
termination
42
small organic molecules that allow enzymes to be effective
coenzyme
43
generally non-protein inorganic molecules that allow enzymes to be effective
cofactor
44
Elements that can insert and remove themselves from the genome. In prokaryotes, they can act as a "stress response: system, allowing for rapid inactivation of genes in response to alteration in environmental conditions.
transposons
45
Cell-surface components or appendages of bacteria that facilitate adhesion or adherence to other cells or to surfaces, usually in the host they are infecting or living in. ____ are a type of virulence factor.
surface adhesins
46
an activator protein is unable to bind to the gene and no transcription takes place until an inducer binds to the activator protein
positive inducible operons
47
allows filtration (movement from the circulation into the nephron tubule) of small molecules while blocking the filtration of plasma proteins)
glomerulus
48
# Name the kidney structure
reabsorption of water, which serves to concentrate the filtrate.
descending loop of Henle
49
Capillaries that supply nutrients to the nephron. Not part of filtration process itself as they are not apart of the nephron
vasa recta
50
# True or False
Salt is PASSIVELY filtered into Bowman's capsule at the glomerulus and does not require active sectretion to become a part of the filtrate.
True
51
Amount of solute per kg of solution. requires reabsoprtion and secretion to be regulated and controlled by the kidney.
blood osmolality
52
How is sugar filtered through the glomerulus and proximal convuluted tubule?
Sugar is passively filtered at the glomerulus and then ACTIVELY reabsorbed in proximal convulated tubule
53
Occur when the binding properties of a macromolecule change as a consequence of a second. ligand binding to the macromolecule and altering its affinity towards the first, or primary, ligand. In Hb, the binding of oxygen to one of the subunits is affected by its interactions with the other subunit
allosteric effects
54
If less water is reabsorbed through the loop of Henle, [more/less] water is eventually excreted in urine
If less water is reabsorbed through the loop of Henle, **more** water is eventually excreted in urine
## Footnote
One of many causes of this could be glucose being trapped in the nephron isntead of being reabsorbed
55
The partial pressure of oxygen in the alveoli must be [higher/lower] than the partial pressure of oxygen in the capillaries. This is b/c oxygen difussed from the aveoli to the alveolar capillaries
The partial pressure of oxygen in the alveoli must be **higher** than the partial pressure of oxygen in the capillaries.
56
begins when the morula develops a fluid-filled cavity, which by the fourth day of development becomes a hollow sphere of cells called the blastula
blastulation
57
the avg molecular weight of an amino acid is...
110daltons
58
How do you figure out how many amino acids are in a protein given the protein's molecular weight?
Divide the protein's weight by the avg weight of an amino acid (110) e.x a protein whose weight is 15 kDa / 110 daltons = 140 aa's in the protein
59
****β-adrenergic receptors are predominant postsynaptic receptors in which division of the nervous system?
The **sympathetic** nervous system
## Footnote
remember, **adrenaline = epinephrine**, a key neurotransmitter/hormone in the sympathetic nervous system
60
The concentration of ligand at which half the receptors are occupied
Kd
## Footnote
Kd for receptors and their ligands is analogous to Km in enzyme-substrate interactions
61
A competitive receptor antagonist (inhibitor) is something that....
Bind to the same sites on the receptor as a ligand and (unlie non-competitive and other allosteric inhibitors) can be displaced with suffiecient quantaties of ligand
62
Enzymes decrease the activation energy of a reaction by stabilizing the ____
transition state
63
The balance point of catalysis. The state corresponding to the highest potential energy along this reaction coordinate
Transition state
64
Acidic amino acids have ____ charges at physiological pH
Negative
## Footnote
Acidic amino acids are those amino acids that have a carboxylic acid group on their side chains at neutral pH, resulting in acidic properties in the molecule. The aqueous solution of these amino acids at physiological pH results in the ionization of the three functional groups present on the amino acids. This results in the** overall charge of -1.**
65
The attractive or repulsive interaction between objects having electric charges
electrostatic interactions
| aka Van der Waals
66
A protein that is 118 amino acids long has how many peptide bonds?
117
## Footnote
There is always one less peptide bond than there is amino acids
67
Process where a metabolite produced early in a pathway activates an enzyme that catalyze a reaction further down the pathway.
feed-forward activation/stimulation
## Footnote
Ex: pyruvate kinase being stimulated by fructose-1,6-biphosphate in glycolysis
68
# True or False
Hyperinflated lungs occur when air gets trapped in the lungs and causes them to overinflate. Hyperinflated lungs can be caused by blockages in the air passages or by air sacs that are less elastic, which interferes with the expulsion of air from the lungs.
True
69
The diaphram has ____ muscle
skeletal
70
The effector neurotransmitter of the diaphram is ....
acetylcholine
## Footnote
when you think muscle contraction NT, think acth!
71
Organisms that undergo a fair amount of cellular activity must use a fair amount of ATP. What cellular process would best support this ATP production?
oxidative phosphorylation
## Footnote
whenever a MCAT question asks about an organism that is complex enough to have a good amount of cellular actrivity, think significant ATP levels, and think oxidative phosphorylation
72
Produces essential precursor ribose-5-phosphate for nucleotide synthesis, necessary for both DNA replication and RNA transcription
pentose phosphate pathway
73
cAMP mediated protein kinase activity is increased when ____ are bound and activated
G protein coupled receptors
74
Largest family of membrane proteins and mediate **most cellular responses to hormones and neurotransmitters**, as well as being responsible for vision, olfaction and taste.
GPCRs
75
The most destructive mutations are ....
frameshift mutations
## Footnote
move stuff around
76
mutation causes the substitution of one amino acid for another
missense mutation
## Footnote
does not always cause mutations, is possible though
77
Involves a single alteration to the DNA base pair that results in the production of a stop codon, thereby terminating protein synthesis prematurely. Results in a shortened protein that may function, but also may not.
nonsense mutation
78
Three-nucleotide deletion in the gene would result in the loss of one amino acid. Is this as devastating as a framseshift mutation?
No. A 3-nucleotide deletion *could* affect the three-dimensional structure of the resulting protein, but this is not as devastating an effect as is a reading frame shift
79
Do intermediates count as products in pathways?
Yes
80
# True or False
If something in a reaction is reduced, then another thing is oxidized
True, this is why they are called reduction-oxidation reactions
81
# True or False
Mitosis involves double-stranded DNA breaks during recombination
False. MEIOSIS features recombination and crossing over, not mitosis
82
What's the mnenonic for southern, western, and northern blots?
83
uses fluorescent DNA probes to bind to chromosomes and could detect a translocation by detecting a gene on an unexpected chromosome
fluorescent in situ hybridization (FISH)
84
generally short peptides that act as a signal fragment that mediates the transport of proteins from the cytoplasm into the nucleus.
nuclear localization signal
85
Rroteins involved in the process of converting, DNA into RNA; bind DNAs and must have DNA binding motifs
transcription factors
86
What is the final acceptor in the ETC
oxygen
87
When the electron transport chain is not available to make energy (ATP) the cells will rely solely on anaerobic respiration. What is another name for this process?
Glycolysis
## Footnote
This process needs to be amped up by the body increasing glucose consumption in order for ATP levels to be normal
88
The process of separating compounds in a mixture by injecting a gaseous or liquid sample into a mobile phase, typically called the carrier gas, and passing the gas through a stationary phase
gas chromatography
## Footnote
shorter retention times = more volatile
89
Long retention times on the size-exclusion chromatography column mean that the oligomers are [large/small], which also means they are more volatile. The converse is also true: short SEC retention times mean the oligomers are [large/small] and less volatile
Long retention times on the SEC column mean that the oligomers are **small**, which also means they are more volatile. Short SEC retention times mean the oligomers are large and less volatile
90
Vitamin D functions to [increase/decrease] serum calcium and ____ levels when they are low
Vitamin D **increases** serum calcium and phosphate levels when they are low
91
Antibodies are secreted by ____ into the blood and are classified as ____ immunity
**B-cells**, classified as **humoral** immunity
92
T-cell mediated response is classified as ____ immunity. nnate immunity refers to the general, non-specific protection the body provides (e.g., tears, skin, complement system)
cell-mediated immunity
## Footnote
cell-mediated immunity involve the destruction of infected cells by cytotoxic T cells, or the destruction of intracellular pathogens by macrophages
93
The term exogenous (wrt hormones) refers to any hormones entering the organism that are ....
**not** produced by the patient's own endocrine glands.
94
antigen presenting cells (APCs) express which class of MHC proteins?
Both MHC class I and II
95
# True or False
All nucleated cells express MHC I
True
96
High citric acid levels suggest increased substrate supply (acetyl-CoA) to the Krebs cycle. This would [postively/negatively] regulate PFK in order to [slow down/speed up] glycolysis, thus [reducing/increasing] the availability of acetyl-CoA to the Krebs cycle
High citric acid levels suggest increased substrate supply (acetyl-CoA) to the Krebs cycle. This would **negatively** regulate PFK in order to **slow down** glycolysis, thus **reducing** the availability of acetyl-CoA to the Krebs cycle
97
Low ATP/ADP and NADH/NAD+ ratios suggest that the energy levels of the cell are ....
**Low**
## Footnote
atp/adp ratio also determines if cell metabolism is predominantly oxidative or glycolytic
98
RT-PCR is performed on RNA, to....
give information on gene expression
## Footnote
RT-PCR is reverse transcription-polymerase chain reaction
99
Each round of beta-oxidation produces....
1 acetyl-CoA, 1 NADH, 1 FADH2, decreasing the fatty acid chain length by two carbons
