MCAT Bio 2014 Flashcards
Is ENDOpeptidase one enzyme, or a group of enzymes?
group
what do ENDOpeptidases do?
break the peptide bonds of NONterminal amino acids
peptidases are AKA?
protease,
proteinase
proteases are AKA?
peptidase
What is protease?
any enzyme that does proteolysis
What is peptidase?
any enzyme that does proteolysis
what’s the fancy word for the enzymatic destruction of proteins?
proteolysis
ENTEROpeptidase is AKA:
enterokinase
What region/part of the body MAKES Enteropeptidases?
cells of the Duodenal mucosa
what gland in the body secretes ENTERopeptidase?
crypts of Lieberkuhn
What does ENTERopeptidase do?
converts trypsinogen (a zymogen) into its active form trypsin
How do proteases and peptidases differ?
they’re the same shit
the Ampulla of Vater is formed by the merging of the ___ and the ___.
pancreatic duct,
common bile
The common bile duct is formed by the merging of the ____ with the ____.
Common hepatic duct,
cystic duct
The duct that goes directly into (or, “comes straight out of”) the Gallbladder is the:
cystic duct
pancreatic duct merges with the common bile duct to form the:
Ampulla of Vater
Common hepatic duct and cystic duct merge to form the:
common bile duct
The ___ duct and cystic duct merge to form the common bile duct.
common hepatic
the Alpha cells of the pancreas produce:
glucagon
the Delta cells of the pancreas produce:
somatostatin
the Beta cells of the pancreas produce:
insulin,
amylin
the Gamma cells of the pancreas produce
pancreatic polypeptide
the Epsilon cells of the pancreas produce:
ghrelin
the ____ cells of the pancreas produce glucagon:
Alpha
the ____ cells of the pancreas produce amylin and insulin:
beta
the ____ cells of the pancreas produce somatostatin
delta
the ____ cells of the pancreas produce **pancreatic polypeptide **
gamma
the ____ cells of the pancreas produce ghrelin
Epsilon
What is a monogenic disorder?
an inherited disorder that is caused by a defect in only ONE gene
What is the # assigned to the sex chromosome?
No. 23
What is an autosome?
any non-sex chromosome.
So chromosomes # 1 - 22 are all Autosomes.
The opposite of an autosome is:
a sex chromoxome
(e.g., X or Y)
A chromosome that’s not a sex chromosome is called a/n:
autosome
T/F:
All sex-chromosome linked diseases are caused by mutations on the X chromosome.
FALS.
Although very rare, there are some “Y-linked” disorders.
The term “dominant” or “recessive” is used for genetic disorders that are [autosomal / sex-linked / either]
either
List 3 well-known Eicosanoids:
leukotrienes,
prostaglandins,
thromboxanes
(1) What’s a missense mutation?
(2) What is the result of a missense mutation?
alteration in a single nucleotide of an amino acid coding sequence
is a point mutation, in which a single nucleotide change results in a different codon that codes for a different amino acid.
Result is a possible change in that specific amino acid, thus creating a change in the primary structure of the protein.
What is a nonsense mutation?
what is the result of a nonsense mutation?
change in the nucleotide sequence,
will create a STOP codon that prematurely cuts off the polypeptide’s synthesis
What’s a frameshift mutation?
the addition/insertion, or deletion, of one or more base-pairs in multiples other than 3
what’s a point mutation?
a change in a *single *nucleotide in a double strand of DNA
What is a transition mutation?
changes a purine nucleotide to another purine (A ↔ G)
OR
a pyrimidine nucleotide to another pyrimidine (C ↔ T).
what’s a transversion mutation?
the substitution of a purine for a pyrimidine
OR
vice versa
What’s a non-frameshift mutation?
the addition or deletion of exactly 3 nucleotides to an amino acid coding sequence,
causing the addition or deletion of an amino acid
In virology, what is the eclipse period?
the time between the injection of viral nukes into the Host, and the appearance of the first fully formed virion
What is a chylomicron?
What is a chylomicron made of?
Large particles of lipoprotein, that consist of:
triglycerides (~ 85-90%),
phospholipids,
cholesterol,
proteins
What is the function of a chylomicron?
transport dietary lipids from the intestines to:
- liver,
- adipose,
- cardiac, and
- skeletal muscle tissue
List the five major groups of lipoproteins that enable fats and cholesterol to move within the watery solution of the blood.
chylomicrons,
VLDL,
IDL,
LDL,
HDL
Very-low-density lipoproteins are made by the ____
liver
(1) What are Apolipoproteins?
(2) Their fcn?
proteins that bind lipids to form lipoproteins.
–They transport the lipids through the lymphatic and circulatory systems.
–Apolipoproteins also serve as
enzyme cofactors, and
ligands for cell-surface receptors
Chylomicrons are identified by a surface marker called:
apoprotein B-48
Plasma lipoprotein lipase hydrolyzes:
chylomicrons
Which of the major lipoproteins is synthesized by the liver?
VLDL
What’s the fcn of VLDL?
to transport triglycerides and cholesterol from liver to adipose tissue
IDL, LDL, and VLDL
Which of the above lipoproteins is a precursor to the synthesis of which? Rearrange and order the above.
VLDL → IDL → LDL
What factors/variables can directly affect the activity of enzymes?
pH,
temperature,
and [substrate] (i.e., substrate concentration)
Which one of the major Lipoproteins has the lowest lipid density?
chylomicrons
Which of the major Lipoproteins has the highest lipid content?
chylomicrons
What effect do enzymes have on activation energy?
↓↓ energy of activation
What effect do enzymes have on the rate of a reaction?
enzymes ↑↑ the reaction’s Rate
What effect do enzymes have on the rate of the reverse reaction?
enzymes ↑↑ the rate of the reverse reaction
T/F:
Enzymes ↑↑ the rate of both the forward and reverse reactions.
true
What effect do Enzymes have on the Keq of a rxn?
none
What effect do enzymes have on the Δ S of a reaction?
none
What effect do enzymes have on the Δ G of a reaction?
none
What effect do enzymes have on the Δ H of a reaction?
none
Do RBCs possess mitochondria?
No
T/F:
RBCs don’t have any organelles.
t
T/F:
RBCs have Na+/K+ pumps.
t.
All cells in the human have Na/K pumps.
The citric acid cycle not only converts sugars, it also accepts _____.
fatty acids and
proteins
Acetyl CoA is made from the breakdown of these fuels:
glucose, or
fatty acids
What product of glucose breakdown can be converted into amino acids?
pyruvate
In order to be optically active, a molecule or compound must be ____.
assymetric
[T/F]:
Symmetric molecules can be optically active.
F. Only asymmetrical molcules can be optically active.
Can fatty acids be converted into glucose via Gluconeogenesis?
yep.
Only ODD-chained fatty acids (i.e., odd number of Carbons) can.
In order for a compound to enter into Glycolysis, that compound must contain at least [#] carbons.
3
What is an isozyme?
Isozymes are enzymes that differ in amino acid sequence but catalyze the same chemical reaction.
For a non-carbohydrate precursor to enter Gluconeogenesis, that precursor must first be converted into:
pyruvate;
oxaloacetate;
dihydroxyacetone phosphate (DHAP)
Oxaloacetate requires a ____ shuttle to cross the inner mitochondrial membrane.
malate
Oxaloacetate requires a malate shuttle to cross the ____ membrane.
inner mitochondrial
Gluconeogenesis can occur in the ____.
–Liver
–Cortex of kidney
What is the role of NAD+ in glycolysis?
to accept high-energy electrons during oxidation
What is the role of FAD in glycolysis?
to accept high-energy electrons during glycolysis
How many carbons does Pyruvate have?
3
Which reaction product in the Glycolysis chain, can isomerize into another compound?
Dihydroxyacetone phosphate ↔ glyceraldehyde 3-phosphate
glyceraldehyde 3-phosphate is AKA
PGAL
PGAL is also called:
glyceraldehyde 3-phosphate
Which reactions within the Glycolysis chain, needs ATP input for energy?
(1) the conversion of glucose to glucose 6-phosphate
(2) conversion of fructose 6-phosphate to fructose 1,6-diphosphate
How much ATP is needed for the conversion of glucose to glucose 6-phosphate?
1
How much ATP is needed for the conversion of fructose 6-phosphate to fructose 1,6-diphosphate.
1
What is pyrophosphate?
simply, 2 phosphate ions (PO4 3-) bonded together
Write out the net reaction for glycolysis:
**Glucose **+ 2 **ADP **+ 2 Pi<em> </em>+ NAD+ →
2 **pyruvate **+ 2 ATP + 2 NADH + 2 H+ + 2 H2O
In what reaction(s) of the Glycolysis chain, is new ATP synthesized?
(1) 1,3-bisphosphoglycerate → 3-phosphoglycerate
(2) phosphoenolpyruvate → pyruvate
RedOx reactions happen in pairs.
If pyruvate is reduced (during fermentation) into lactic acid or ethanol, then what is oxidized?
NADH is oxidized back into NAD+
What is the Cori cycle?
the reaction pathway in which lactate (produced by anaerobic glycolysis) in the muscles moves to the liver and is converted to glucose, which then returns to the muscles and is metabolized back to lactate.
From one glucose, we ultimately get [#] NADH.
(assume it’s Aerobic respiration)
2 from glycolysis
+
2 from decarboxylation of Pyruvate into Acetyl CoA
+
6 from TCA cycle
____________________
Total = 10 per Glucose
To start the TCA cycle, you react Acetyl CoA with Oxaloacetate to create ______.
citrate
To start the TCA cycle, you react Acetyl CoA with _____ to create Citrate.
Oxaloacetate
Which high-energy intermediates “carry” the electrons from the TCA cycle to the electron transport chain?
NADH and FADH2
Which reactions within the TCA cycle, generate NADH?
(1) isocitrate → alpha-Ketoglutarate
(2) alpha-Ketoglutarate → succinyl-CoA
(3) malate → oxaloacetate
Which reactions within the TCA cycle, generate FADH2?
succinate → fumarate
The final electron acceptor in the electron transport chain is:
Oxygen
The electron transport chain can be organized into 4 complexes. These are:
Complex 1: NADH dehydrogenase
Complex 2: succinate-Q oxidoreductase
Complex 3: b-c1 complex
Complex 4: cytochrome oxidase complex
and
Coenzyme Q10 (ubiquinone)
The electron transport chain begins when NADH gives its electrons directly to _____, which is a part of Complex 1.
FMN (flavin mononucleotide)
From Complex 1, the next step in the Electron Transport Chain are when the electrons are passed to _____.
coenzyme Q
In the ET Chain, coenzyme Q passes electrons to _____.
Complex 3
The last step in the ET Chain occurs when electrons from _______, which is a component of Complex 4, is given to an Oxygen.
cytochrome a3
When arriving at the ET Chain, the FADH2 molecules give their electrons to _____, which in turn will give the electrons to _____.
Complex 2
coenzyme Q
Why is cyanide deadly?
it blocks the final transfer of electrons to Oxygen
Why is dinitrophenol (DNP) deadly?
it destroys mitochondrion’s ability to generate a proton gradient
Why do we inhale Oxygen? Why is this gas critical for us?
Oxygen’s role is to be the final electron acceptor in the ET chain.
T/F:
Aldosterone is made in the adenohypophysis.
F.
Aldosterone is from the adrenal cortex.
Where in the cell, does fermentation take place?
cytoplasm
Where in the cell does glycolysis occur?
cytoplasm
Where in the cell does the conversion of pyruvate to acetyl CoA, occur?
mitochondrial matrix
Where in the cell does the TCA cycle, occur?
mitochondrial matrix
Where in the cell is the ET chain, located?
inner mitochondrial membrane
What is the NET yield of ATP from substrate-level phosphorylation?
a net of 4 ATP
(2 from Glycolysis; and 1 from each turn of the TCA cycle = 4)
How many FADH2 are generated by the TCA cycle?
Each turn of the Krebs cycle, gives you 1 FADH2.
In an anaerobic environment, eukaryotic cells can generate __[#]__ ATP.
2
A prokaryote generates __[#]__ ATP from aerobic respiration.
38
A eukaryote generates __[#]__ ATP from aerobic respiration.
36
Fatty acids can be used as cellular fuel, by taking them into the mitocondrial matrix.
Then, inside the matrix, the fatty acids can be converted into ____.
acetyl CoA
Inside the mitochondrial matrix, the reaction to turn fatty acids into acetyl CoA is called:
beta-oxidation
A single beta-oxidation reaction, that generates 1 acetyl-CoA from a fatty acid, generates high-energy-intermediates.
(1) **Which **high-energy-intermediates are made?
(2) How many hi-energy-intermediates are made?
1 NADH,
and
1 FADH2
The removal of the amine moiety from an amino acid is accomplished by this enzyme:
transaminase
The removal of an amine moiety from an amino acid, by transaminases, results in molecules called _____.
alpha-keto acids
To turn a triglyceride into cellular fuel, the glycerol molecule is converted into _____, which will then enter Glycolysis.
PGAL
How can you tell that a molecule is aromatic?
What determines if a molecule is aromatic?
Aromatic compounds comply with All of the following:
- (1)* are Planar
- (2)* are conjugated - i.e., have a minimum of 2 double bonds, in a double-single-double alternating config
- (3)* HUCKEL’s RULE: have 4n + 2 # of pi electrons (lone-pair electrons count)
In a somatic cell, how many chromosomes are present after the S phase?
46
T/F:
After the S phase, there are 96 chromosomes in a human somatic cell.
F. Somatic cells always have 46 (i.e., “2n”) chromosomes. No matter what.
Gyrase is a type of _____ase.
topoisomerase
What does Gyrase do?
How does it do that?
It relieves the severe supercoiling that Helicase induces when Helicase unwinds DNA, by breaking the bonds between nucleotides to relax the DNA.
Deoxyribose and ribose are different at Carbon # ____.
2
(1) List the prokaryotic ribosomal subunits, in Svedberg units.
(2) What is the combined sedimentation coefficient for prokaryotes, in Svedberg units.
30S
50S
combined = 70S
(1) List the eukaryotic ribosomal subunits, in Svedberg units.
(2) What is the combined sedimentation coefficient for eukaryotes, in Svedberg units.
40 S
60S
combined = 80S
What is SSBP?
What does it do?
Single strand binding protein
Fcn: to keep the replication fork open for the Primase to attach and synthesize an RNA primer.
Will an Enantiomer (mirror-image, but Non-superimposable) rotate light in the opposite direction of the original molecule?
Yep.
(d)-molecule is the same thing as ______.
(+)-molecule
(+)-molecule is the same thing as ______.
(d)-molecule
(-)-molecule is the same thing as ______.
(l)-molecule
(l)-molecule is the same thing as ______.
(-)-molecule
T/F:
(D)-molecule is the same thing as (d)-molecule.
F.
Any process that separates enantiomers is called: ___
resolution
An anticodon is found on a [mRNA / tRNA / DNA].
tRNA
A codon is found on a [mRNA / tRNA / DNA].
mRNA
The sk-loop of tRNA contains the _____.
anticodon sequence
The Shine-Delgarno sequence is rich in [purines / pyrimidines].
purines
T/F:
In order for an organic molecule to be optically active, it must possess chiral centers.
tru
Can Enantiomers be separated by distillation?
No
Can Enantiomers be distributed by recrystallization?
no
The Shine-Delgarno sequence is located [#] base-pairs upstream of the 5’ end of the start codon on an mRNA.
10
The Shine-Delgarno sequence is found on [DNA / mRNA / tRNA].
mRNA
What reaction pathway in the body synthesizes GTP?
TCA (Krebs) cycle
Which amino acids are known as “helix breakers”?
proline
Which amino acids are also considered as imino acids?
proline
How many amino acids are Achiral?
1
(glycine)
Where in the cell does post-transcriptional modification occur?
Rough ER, and
Golgi
In the body, oxidation of Lipids takes place in the _____.
mitochondria
Protein digestion starts in the ___.
stomach
Protein digestion in the stomach is made possible by an enzyme called ___.
Pepsin
Digestion of proteins begins in the stomach, and is completed in the _____.
small intestine
Phenylalanine is converted into another amino acid called ___.
tyrosine
Tyrosine is a precursor of ____.
dopamine and
norepinephrine
What is a Barr body?
a permanently inactivated X-chromosome
T/F:
Males have Barr bodies.
Fals. Only Females!
T/F:
Females have Barr bodies.
Tru
Females have two X chromosomes. Are both expressed?
No.
Normal females have XX, and one of these X chromosomes is inactivated and turned into a Barr body.
If a gene is “imprinted”, that means that the gene is ____.
methylated.
A person w/ 2 Barr bodies has how many X chromosomes?
You always have 1+n X chromosomes and n Barr bodies.
Give 4 High Yield facts about autosomal dominant inheritance.
- Only 1 copy of the mutant gene is needed to have the disease.
- Traits DO NOT SKIP generations
- There’s an equal number of Males and Females who get the disease.
- Father’s can give the disease to their sons.
Can genetic mutations lead to abnormal carbohydrate function?
NO.
Mutations alter proteins, not carbs.
For sex-linked disorders, which inheritance pattern/type will show “skipped generations”?
X-linked RECESSIVE
T/F:
A man with an X-linked recessive disease can pass it on to his sons.
Fals.
Fathers give their sons the Y chromosome. So men who have an X-linked disease, got it from their MOMs.
Males get their Y chromosome from [mom / dad / either].
ONLY from Dad !!!
T/F:
DNA Polymerase proofreads the new DNA strand during replication/synthesis.
Tru.
DNA Polymerase proofreads as it synthesizes.
The protein, that relaxes the tension caused by the opening of the replication fork, is called ___.
gyrase
If a heterozygous man and heterozygous woman both carry an autosomal recessive gene, there is a ____ percent chance that they will have a child with the active disease.
25 %
(draw a Punnett square to see why)
If a heterozygous man and heterozygous woman both carry an autosomal recessive gene, there is a ____ percent chance that they will have a healthy child with no abnormal genes.
25 %
(draw a Punnett square to see why)
B cells are made in the ____.
Bone marrow.
T-cells are made in the ____.
bone marrow
T-cells go to the ____ to mature.
Thymus
Okazaki fragments are bonded together by ____ase.
DNA ligase
Which has a Lower affinity for oxygen:
myoglobin or hemoglobin?
Hemoglobin
Which has a Higher affinity for oxygen:
myoglobin or cytochrome oxidase?
cytochrome oxidase
Most viruses acquire their envelopes from the ____.
Host’s plasma membrane
HSV-1 acquires its envelope from ______.
the Host’s nuclear membrane.
All invading particles (viruses, bacteria, fungi, etc.) have ____ , AKA _____ that allow them to be detected by the Host’s immune system.
surface markers, AKA antigens
Define “virulence”.
ability to cause infection
T/F:
HSV-1 can be spread thru skin contact.
tru
How does HSV-1 get from skin to your nervous system?
HSV-1 travels from skin to a Ganglion, via retrograde movement along the axons of afferent sensory nerve fibers.
HSV-1 travels, from skin, along axons of [afferent / efferent] [motor / sensory] nerve fibers.
afferent;
sensory
During its latency period, HSV-1 “hides” in your body in ____.
ganglia
(usually the Trigeminal nerve’s ganglion)
In Virology, what is tegument?
a cluster of proteins that is located between the virus’ capsid and envelope.
Teguments are associated with this family of viruses:
Herpesviruses
Herpesviridae are a family of [single / double]-stranded [DNA / RNA] viruses.
double
DNA
Tyrosine is created from this amino acid:
phenylalanine
phenylalanine is a precursor to this amino acid:
tyrosine
What is the Michaelis-Menten equation for competitive inhibition?
Vo =
(Vmax* [S]) ** /** ([S] + Km )
A reaction has a certain Km and Vmax. If you add a competitive inhibitor to the reaction, the Km will [increase / decrease / not change].
increase
A reaction has a certain Km and Vmax. If you add a noncompetitive inhibitor to the reaction, the Vmax will [increase / decrease / not change].
decrease
EXPLANATION:
Non-competitive inhibition is a form of mixed inhibition where the binding of the inhibitor to the enzyme reduces its activity but does not affect the binding of substrate. As a result, the extent of inhibition depends only on the concentration of the inhibitor. Vmax will decrease due to the inability for the reaction to proceed as efficiently, but Km will remain the same as the actual binding of the substrate, by definition, will still function properly.
A reaction has a certain Km and Vmax. If you add a noncompetitive inhibitor to the reaction, the Km will [increase / decrease / not change].
Not change
EXPLANATION:
Non-competitive inhibition is a form of mixed inhibition where the binding of the inhibitor to the enzyme reduces its activity but does not affect the binding of substrate. As a result, the extent of inhibition depends only on the concentration of the inhibitor. Vmax will decrease due to the inability for the reaction to proceed as efficiently, but Km will remain the same as the actual binding of the substrate, by definition, will still function properly.
A reaction has a certain Km and Vmax. If you add a competitive inhibitor to the reaction, the Vmax will [increase / decrease / not change].
Not change
Hexokinase catalyzes the reaction of _____ to _____.
turns glucose into glucose-6-phosphate
What reaction does Phosphoglucomutase catalyze?
the interconversion of glucose 1-phosphate and glucose 6-phosphate.
The glucose subunits within glycogen are bonded to each other through _____ linkages.
α─1,4
T/F:
The liver lacks glucose-6-phosphatase.
Fals
Glucose-6-phosphatase is found in ____ but is lacking in ____, although both these organs contain glycogen.
the Liver;
skeletal muscle
The enzyme glycogen phosphorylase [creates / breaks down] glycogen.
breaks down
The enzyme that catalyzes the rate-limiting step in Glycogenolysis is ____.
glycogen phosphorylase
Glycogen phosphorylase breaks down glycogen into:
glycogen, and glucose-1-phosphate
T/F:
Glucose-6-phosphate cannot freely diffuse out of the cell.
Tru.
That’s why glucose-6-phosphate is hydrolyzed into glucose.
VLDL transports _____, from _____ to ____.
triglycerides and cholesterol;
the liver;
adipose tissue
Fatty acids can be converted into glucose, via Gluconeogenesis; HOWEVER:
Only ODD-chained fatty acids (i.e., odd number of Carbons) can.
The time period, between the injection of viral nukes into the Host and the appearance of the first fully formed virion, is called the _____.
eclipse period
The “c” in the term cDNA stands for:
complementary
What is cDNA, or “complementary DNA”?
complementary DNA (cDNA) is DNA synthesized from a messenger RNA (mRNA) template in a reaction which is catalysed by the enzymes reverse transcriptase and DNA polymerase
Why do scientists or researchers use cDNA?
cDNA is often used to clone eukaryotic genes inside prokaryotes.
Where in nature is cDNA seen?
cDNA is produced naturally by retroviruses (such as HIV) and then integrated into the host’s genome, where it creates a provirus.
Introns and exons are terms that refer specifically to [tRNA / mRNA / rRNA / DNA].
mRNA
T/F:
Introns and exons are not features of eukaryotes.
Fals.
Introns and exons are found in organisms of all of the biological kingdoms. They are also found in viruses.
T/F:
After the virus invades the Host, Reverse transcriptase is synthesized by the Host cell’s machinery.
Fals.
Reverse transcriptase is Not made by eurkaryotic cells. The Retrovirus carries its own reverse transcriptase and brings it into the Host cell.
T/F:
Retroviruses are diploid.
tru.
B cells mature in this part of the body.
Bone marrow.
Bacterial growth when graphed, follows a _____-shaped curve.
S shaped
The 4 phases of the bacterial life cycle are:
- lag phase
- exponential growth phase
- plateau / stationary phase
- bacterial death phase
The chronological order of events, from a virus’ invasion into the Host cell, to viral replication, are:
- target cell binding (“tissue tropism”)
- Attachment via host cell’s surface surface receptors.
- Penetration
- Uncoating
- Viral synthesis
What does “tissue tropism” mean?
each virus (species) has a specific target tissue preference
What is translocation?
the rejoining of broken chromosomes’ ends
T/F:
Some prokaryotes have cell walls made of chitin.
Fals.
The cell walls of prokaryotes are made from peptidoglycan.
What does “mass action” mean?
refers to the Net movement of mass (from location to another)
T/F:
The process of endocytosis requires ATP.
tru
Insulin is a [peptide / tyrosine / steroid] hormone.
peptide
T/F:
Insulin is lipid soluble.
Fals.
Insulin is water soluble. Insulin is a peptide hormone.
T/F:
Prolactin is water-soluble.
tru
Three physiologic causes of a drop in Blood Pressure are:
- arteries or arterioles dilate
- heart rate ↓↓↓
- a ↓↓ in blood volume
DNA tends to be [negatively / positively / not] charged.
negatively
Do histones have a charge?
If so, which?
positive
Histones are [acidic / basic / neutral].
Basic
Fungi spend a lot of their time in a [haploid / diploid] state.
haploid
What happens to somebody who’s given thermogenin?
↑↑ body temperature
Teichoic acids are found in [gram + / gram-neg / neither] bacteria.
ONLY Gram Positive
A specific type of covalent bond found in the cell walls of gram + bacteria is the ______ bond.
phosphodiester
Two important “acids” found in the cell walls of gram + bacteria are:
teichoic acids; &
lipoteichoic acid
N-acetyl muramic acid is found only in this organism:
bacteria
Mycoplasma is this type of organism:
bacteria
Mycoplasma lack this organelle/component, which almost all other species of bacteria have:
cell walls
The release of any neurotransmitter from the axon terminal into the synaptic cleft requires an influx of _____.
Calcium ions
Glycosaminoglycans (GAG) have [no // a net positive // a net negative] charge at normal body pH.
net Negative
What is the difference between PRIMARY active transport, versus SECONDARY active transport?
Primary A.T. consumes ATP directly.
Secondary A.T. burns ATP to create a concentration gradient. The new concentration gradient is what “moves” the molecule across the membrane.
The cells which secrete surfactants are called _____.
pneumocytes
Where inside the cell does GLUCONEOGENESIS occur?
in BOTH the mitochondria and cytosol
Actin is a [microfilament // microtubule].
microfilament
Teichoic acids are found in [gram + / gram negative / both / neither] bacteria.
only gram POSITIVE
A specific type of covalent bond found in the cell walls of gram positive bacteria is the _____.
phosphodiester bond
Two important “acids” found in the cell walls of gram POSITIVE bacteria are:
- lipoteichoic acid
- teichoic acids
N-acetyl muramic acid is found only in this organism:
bacteria
Mycoplasma is this type of Organism (fungus, bacteria, virus, etc.):
bacteria
Mycoplasma lack this component/structure, which almost all other species of bacteria have:
cell walls
The release of any neurotransmitter from the axon terminal into the synaptic cleft requires an influx of _____.
Ca++
Glycosaminoglycans (GAG) have [a net positive / a net negative / no] charge at normal body pH.
net negative
What is the difference between PRIMARY active transport, versus SECONDARY active transport?
Primary A.T. consumes ATP directly.
Secondary A.T. burns ATP to create a concentration gradient. This new concentration gradient is what “moves” the molecule across the membrane.
The cells that secrete surfactants are called ____.
pneumocytes
Where inside the cells does GLUCONEOGENESIS occur?
in BOTH mitochondria & cytosol
Actin is a [microfilament / microtubule].
microfilament
T/F:
Dendrites can Not synapse with other dendrites.
Fals.
Yea they can.
Which receptor is slower? Nicotinic or Muscarinic?
Muscarinic
What does superoxide dismutase do?
Catalyzes dismutation of superoxide radical into hydrogen peroxide
What are the major areas/surfaces of the body where cilia are found?
- trachea and bronchi of the resp tract
- lumen of the Small intestine
- fallopian tubes
Conduction of a cardiac impulse thru Purkinje fibers depend on [sodium / ion]-dependent channels.
sodium
On a myelinated neuron the greatest concentration of Na+ -ion channels is found on the:
Nodes of Ranvier
As the radius of an axon ↓↓ , the speed of an action potential:
↓↓↓
(see Poiseuille’s Eqn)
- Which organism causes toxoplasmosis?
- Which species is that pathogen?
a protozoan, named Toxoplasma gondii
The Electron Transport Chain accepts these 2 substrates/intermediates:
NADH,
FADH2
NAD+ serves as a substrate for [glycolysis / Krebs / ETC].
Glycolysis, & Krebs cycle
Does tubulin consist of 1 polypeptide, or more than 1?
Tubulin is a globular heterodimer, made of 2 peptide chains?
Ca 2+ must bind to this component of a sarcomere, to cause the actin-myosin interaction to occur:
troponin C
Another name for the THICK filament in a sarcomere is:
myosin
Another name for the THIN filament in a sarcomere is:
actin
Myosin is a [microfilament / microtubule].
microfilament
Actin is a [microfilament / microtubule].
microfilament
The neuromuscular endplate region is mediated by ions of this element:
Sodium
Define sarcolemma
cell membrane of striated muscle cells
What are T-tubules?
invaginations of the sarcolemma
Inside each skeletal muscle fiber, ions of this element have to be released in order for the muscle power stroke to occur:
calcium
Describe labile cells.
Labile cells, are cells that are in constant need of cell division to replace dead/damaged cells.
Give 3 examples of “labile” cells:
- skin
- tympanic membrane
- GI tract
Which of these cells can NOT divide?
- pancreatic
- liver
- nerve
- cardiac
nerve cells, and cardiac
Hyperpolarization of a cell occurs when ____ exits that cell.
K + ions
Which muscle types are T-tubules found in?
skeletal
cardiac
Depolarization of the T-tubule membrane triggers the release of _____ from the _____, thus causing muscle contraction.
calcium;
sarcoplasmic reticulum
Which muscle types have myosin light chain kinase?
smooth
The acquired immune system consists of 2 categories/components:
cell-mediated; and
humoral
- Which muscle types have troponin?
- Tropomysin?
skeletal, and
cardiac
Which hormone inhibits the secretion of ACTH from the pituitary, via negative feedback?
cortisone
The 3 functions of T-cells are:
- activate B-cells
- stimulate **macrophage **growth
- destroy foreign invaders and abnormal tissue
The part of the brain responsible for motor coordination and balance is:
cerebellum
The part of brain responsible for controlling respiratory rate, and heart rate:
medulla
Inhibin is secreted by these cells:
Sertoli cells
Sertoli cells secrete ______
inhibin
What hormone from the hypothalamus stimulates the pituitary to release FSH?
GnRH
Gonadotropin-releasing hormone
What hormone from the hypothalamus stimulates the pituitary to release LH?
GnRH
gonadotropin-releasing hormone
GnRH (gonadotropin-releasing hormone) is secreted by the _____.
hypothalamus
GnRH (gonadotropin-releasing hormone), from the hypothalamus, tells the pituitary to secrete ____.
FSH,
and LH
This hormone, from the hypothalamus, stimulates the release of prolactin from the pituitary gland:
TRH
(Thyrotropin-releasing hormone);
also called
TRF (thyrotropin-releasing factor)
This hormone, from the hypothalamus, triggers the release of TSH from the pituitary gland:
TRH
thyroid-releasing hormone
This hormone, from the hypothalamus, triggers the release of ACTH from the pituitary gland:
CRF
corticotropin-releasing factor
What does a trophic hormone do?
tells other glands to secrete their own hormones
What characteristic distinguishes the EXOcrine system?
uses ducts to release active compounds
What are the 3 major proteins found in serum/plasma?
albumin,
globulins,
fibrinogen
What hormone is known to suppress levels of phosphorous?
parathyroid hormone
What causes hyperpolarization of a neuron?
excessive efflux of K+ out of a neuron
What does Vitamin D do in the body?
↑↑ absorption of Ca2+ from the intestine, thus promoting bone formation and mineralization
What hormone helps convert Vitamin D to its active form?
parathyroid hormone
Bile salts are made in the _____
liver
Epi and Norepi are synthesized by these cells of the adrenal medulla:
chromaffin cells
High levels of fat metabolism leads to ↑↑ levels of _____ in the blood
ketone bodies
Ketone bodies are end products of _____ metabolism
fat
Gap junctions are particularly abundant in the cells of these organs:
heart,
and smooth muscle
Thyroid hormone ↑↑ the basal metabolic rate by ______.
stimulating protein synthesis and ↑↑ the activity of the Na/K-ATPase.
Which hormone(s) lower blood volume?
atrial natriuretic peptide
What effect does calcitonin have on the kidneys?
blocks tubular reabsorption of Calcium and Phosphorous, so those minerals are lost in the urine.
The active form of Vitamin D is called:
Cholecalciferol
(or 1,25-dihydroxycholecalciferol)
Where is the receptor for cortisol located on a cell?
on the nuclear envelope
After cortisol diffuses into the cell and binds to a receptor on nuclear envelope, what happens next?
the cortisol receptor complex binds to a specific DNA region to activate gene transcription
Where on a cell is the receptor for a lipid hormone, located?
lipid hormone = steroids
All steroids bind to receptors on the nucleus
Which steroid hormones activate a cell by 2nd-messenger system?
NONE of the lipid-soluble hormones need 2nd-messenger or CAMP. Steroids bind directly to receptor, on nuclear envelope, or found in cytosol.
Which hormone(s) require a 2nd-messenger system to move “signal” from cell membrane receptor to the nucleus?
ALL peptide hormones need 2nd-messenger systems
What binds to alpha-2 receptors?
norepi
What effect does cortisol have on protein?
causes ↓↓ in synthesis of protein, AND
causes ↑↑ in Catabolism of proteins
What in a person’s blood work is/are sign(s) of elevated cortisol levels?
↑↑ amino acids in bloood;
↑↑ in blood sugar
Which hormones released by the anterior pituitary are NOT peptide hormones?
They’re ALL peptide hormones
Using arrows, list the pathway that shows how the 3 tyrosine-derivatives are made from phenylalanine:
Phenylalanine → Tyrosine → L-dopa → Dopamine → Norepinephrine → Epinephrine
What cells in digestive system secrete intrinsic factor?
the same parietal/oxyntic cells that secrete HCl
List all the ENDOcrine glands:
Adrenal cortex
Adrenal medulla
Hypothalamus
Islets of Langerhans
Ovaries
Parathyroid gland
Pineal gland
Pituitary
Testes
Thyroid
p. 278 of Kaplan
T/F:
Epinephrine and norepinephrine are responsible for the “fight or flight response.”
Fals (partly)
ONLY norepinephrine
Which neurotransmitter(s) is/are inhibitory?
GABA
Glycine
(Dopamine can be Both excitatory and inhibitory)
List the phases of the menstrual cycle:
- menstruation
- follicular / proliferative phase
- ovulation
- luteal / secretory phase
The vas deferens connects the _____ to the ______.
epididymis;
prostatic urethra
The 2 vas deferens (1 from each testicle) merge to form the ____.
ejaculatory duct
Semen is produced by the ingredients of all these glands:
prostate,
seminal vesicles,
bulbourethral gland
These glands contribute to the alkalinity of semen:
prostate;
bulbourethral gland
Germ cells are ____ploid.
diploid
(gametes are Haploid)
Where are Sertoli cells located?
walls of the seminiferous tubules
The final stages of sperm maturation occur in the _____.
epididymis
Define interstitium.
a thing, or a region, which is between other structures
Do spermatogonia divide by mitosis, or by meiosis?
mitosis
During gametogenesis, sister chromatids remain paired with each other until this stage:
until anaphase of the 2nd meiotic cell division
T/F:
Genetic recombination occurs between sister chromatids
Fals.
Gen recomb occurs between homologous chromosomes, NOT sister chromatids
Where do mitochondria in sperm get their energy?
from fructose
The fructose that feeds/energizes sperm, comes from this part of the body:
seminal vescicles
ACTH stimulates the adrenals to:
release glucocorticoids
The opposite of a “direct” hormone is a/n ____ hormone.
trophic
- How are Trophic hormones similar to Direct hormones?
- How are they different from Direct hormones?
Like “direct” hormones, “trophic” hormones also bind to receptors on organs. But rather than having an immediate effect, they cause the release of effector hormones.
So trophic hormones are an intermediate.
ADH is secreted in response to ____.
↑↑ blood osmolarity
↓↓ blood volume
What part of body detects changes in blood osmolarity?
osmoreceptors
What part of the body detects changes in blood volume?
baroreceptors
ADH acts on this part of the body:
collecting duct
In terms of physiology, what does ADH do to achieve ↑↑ blood pressure and volume?
↑↑ permeability of duct to H2O, so water is retained in the body
What are signs of somebody suffering from HYPERthyroidism?
↑ activity levels
↑ body temp
↑ respiratory rate
↑ heart rate
↓↓ weight
intolerance to heat
- What is cretinism?
- What is its cause?
- metal retardation and developmental delay
- thyroid hormone deficiency
Where are C-cells found?
thyroid
The _____ cells of thyroid produce thyroid hormones.
follicular
The _____ cells of the thyroid produce calcitonin.
C-cells
The effects of cortisol/cortisone are:
↑↑ gluconeogenesis
↓↓ protein synthesis
↓↓ inflammation
↓↓ immune response
Renin is secreted by ____ cells.
granular cells of the **juxtaglomerular apparatus **of the kidney
Somatostatin blocks this hormone:
Insulin; and
Glucagon
T/F:
LH causes (mens’) interstitial cells to produce testosterone.
tru
Why is testosterone important for males?
- Spermatogenesis
- male embryonic differentiation
- male development during puberty
Testosterone provides negative feedback to these hormone(s):
FSH;
GnRH;
LH
What is androgen insensitivity syndrome?
a genetic male (XY) has secondary female sexual characteristics
What is the etiology for androgen insensitivity syndrome?
receptors for testosterone are absent
Type ____ Diabetes is an autoimmune disorder
1
Insulin-dependent diabetes mellitus is AKA ____.
type 1 diabetes
Birth control pills work by blocking this hormone(s):
FSH;
LH
What happens in the follicular phase of the menstrual cycle?
- menstrual flow begins (i.e., menstruation from the previous cycle
- GnRH secretion from hypothalamus → an ↑↑ in FSH and ↑↑ in LH
- FSH and LH cause development of several ovarian follicles
- Follicles secrete estrogen
- Estrogen stimulates endometrium’s growth, revascularization, and glandularization of the decidua
- Follicles secrete estrogen
During which phase of the menstrual cycle does estrogen peak?
in both the proliferative/follicular phase and the luteal/secretory phase
During which phase does progesterone spike?
secretory/luteal
What happens during the secretory phase?
- LH turns ruptured follicle into corpus luteum
- corpus lutem secretes progesterone, which maintains the uterine lining, thus facilitating emplantation of embryo
- both estrogen and progesterone reach high levels, which give negative feedback to GnRH, FSH, and LH
Erythropoietin is secreted by ______ in response _____.
kidney;
low levels of oxygen in the blood
Why can the heart be considered an endocrine gland?
heart secretes atrial natriuretic peptide (ANP)
Why can thymus be considered an endocrine gland?
thymus releases thymosin
What is the function/action of glucocorticoids?
↑↑ blood glucose leel;
↓↓ protein synthesis
What is the function/action of mineralocorticoids?
↑↑ water reabsorption in the kidneys
What is the function/action of norepinephrine?
↑↑ blood glucose level;
↑↑ heart rate
What is the function/action of somatostatin?
suppress the secretion of glucagon and insulin
What is the function/action of erythropoietin?
stimulates the bone marrow to ↑↑ production of red blood cells
What is the function/action of ANP?
involved in osmoregulation (helps regulate salt and water balance)
What is the function/action of thymosin?
stimulates T-lymphocyte development
The primary oocytes of a female infant are stuck in the ____ phase of Meiosis [#] until time for ovulation.
Prophase 1;
1
When does a secondary oocyte complete Meiosis 1?
Trick question!
PRIMARY oocytes do Meiosis 1 (to turn into secondary oocytes). So secondary oocytes do Meiosis 2, not Meiosis 1.
When does an oocyte complete Meiosis 1?
Primary occytes are stuck in Prophase 1 of Meiosis 1, until hormonal signals during a menstrual cycle stimulate several primary oocytes, in the ovary, to compete among themselves to finish Meiosis 1 and become secondary oocytes.
When does a secondary oocyte complete Meiosis 2?
only after fertilization
T/F:
All primary oocytes are formed while a female is still an embryo in her mother’s womb.
tru
When fertilization occurs, the nuclei of the sperm and the egg do not fuse, until:
until the egg extrudes the 2nd polar body, and matures into an ovum
What is an ootid?
a zygote-precursor cell that contains the separate nuclei of both the sperm and the egg.
When menstruation occurs, a woman loses not a mature ovum, but rather a _____.
secondary oocyte that’s frozen in meiosis
When talking about ovaries, what is a follicle?
a primary oocyte surrounded by granulosa cells
The female equivalent of the interstitial cells of Leydig is:
the thecal cells
Define corona radiata.
the name given to the granulosa cells, surrounding the ovum and the ovum’s zona pellucida, after ovulation.
During the first half of the menstrual cycle, estrogen is made and secreted by the ____ cells.
granulosa cells in the ovarian follicle
The corpus luteum makes this hormone(s):
- progesterone, and
- estrogen
Where, in the effector cell, is the receptor for estrogen located?
in the cytoplasm
In terms of the endocrine system physiology, why does menstruation occur?
because when corpus luteum degenrates, it no longer secretes progesterone nor estrogen. The drop in these 2 hormones leads to shedding of the endometrial lining.
T/F:
high levels of estrogen inhibit the secretion of LH and FSH.
tru
What causes the LH surge that will trigger ovulation?
the gradual ↑↑ in estrogen levels during the follicular phase
How does the birth control pill do its job?
pill contains estrogen, which forces estrogen levels in the blood to remain high.
High estrogen levels block ovulation b/c constantly high estrogen levels inhibit the secretion of LH, FSH, and GnRH
Ovulation occurs at around Day # ________ of the menstrual cycle.
14
Menstruation begins at around Day # ____ of the menstrual cycle.
1
After the blastocyst implants into the endometrium, ____ acts as a substitute for LH.
hCG
hCG acts as a substitute for this hormone:
LH
- What is the role/action of hCG?
- How does it achieve that function?
- Maintains endometrium, by keeping up the supply of estrogen and progesterone
- acts as a substitute for LH by stimulating corpus luteum to make estrogen and progesterone
During pregnancy, corpus luteum is necessary during [1st trimester / 1st and second trimester / 3rd trimester only / during ALL of pregnancy / is NOT necessary during pregnancy].
1st trimester
Why is corpus luteum not necessary after 1st trimester?
placenta will secrete enough estrogen and progesterone to maintain the endometrium
Why is the yolk sac important in human embryology?
first red blood cells are formed there
Approx _____ % of filtered Na+ is reabsorbed in the prox convoluted tubule.
67
Approx 67 % of Na is reabsorbed in the ____ of the kidney.
prox. convoluted tubule
cholecystokinin is released into the alimentary canal by cells which are located in the _____.
duodenum, and
prox jejunum
- What is the macula densa?
- What does it do?
a receptor within the juxtaglomerular apparatus that responds to low NaCl levels in the fluid entering the distal nephron
Where in the body are podocytes located?
In the Bowman’s capsule
The kidney filtration barrier is made of these 3 structures:
- capillary endothelium
- basement membrane
- filtration slits
When talking about the heart, what is preload?
the end-diastolic pressure that stretches the right or left ventricle of the heart, as measured by the volume of blood in the ventricle at the end of diastole (“dub”)
What is Starling’s first law?
an ↑↑ in venous blood returning to the heart, causes an ↑↑ in cardiac output.
An ↑↑ in Preload, causes an ↑↑ in total blood volume ejected by the heart.
What is cardiac output?
amount of blood pumped out by the heart
Define afterload.
the resistance, to blood flow, created by the Aorta
What is Starling’s second law?
An ↑↑ in afterload causes an ↓↓ in the amount of blood ejected by the heart, and ↑↑ the total blood volume in the ventricle for the next heart contraction (“lub”).
B/c the blood volume inside the ventricle is ↑ , the ventricle will contract with greater force on the next contraction.
The part of the brain responsible for involuntary breathing is located in the ______.
the medulla, and
pons
What is the normal expected hematocrit for a healthy person?
~ 45 percent
Macrophages are derived from ___ cells.
monocytes
Monocytes are synthesized in the ____ and are precursors to ____ cells.
- bone marrow
- macrophage
Epimysium is the connective tissue sheath that covers the _____.
entire muscle
______ is the connective tissue sheath that covers the entire muscle, and it is continuous with the tendon.
epimysium
T/F:
Epimysium is continuous with the tendon.
tru
What is a fascicle?
a bundle of muscle cells
- What is a perimysium?
- What does it do?
connective tissue sheat that surrounds a fascicle
- What is endomysium?
- What does it ensheath?
connective tissue that surrounds a single muscle cell/fiber
Endomysium is created by ___ cells.
fibroblast
Actin is the _____ filament, while myosin is the ____ filament.
- thin;
- thick
(mnemonic: “tough actin’ THIN-Actin”)
What’s a proprioceptor?
a receptor that provides info about the movement or position of a body part
The Golgi tendon organ, and the muscle spindle are types of _____.
proprioceptors
The Golgi tendon organ lies in [series / parallel] with the muscle and it is sensitive to changes in _____.
- series
- tension
The muscle spindle lies in [series / parallel] with the muscle and it is sensitive to changes in _____.
parallel;
length
These specific types of tissue can generate action potentials:
- (some) cardiac myocytes
- neurons, and
- skeletal muscle
Cardiac myocytes that can generate action potentials have channels that are selective for this/these ions:
Na,
Cl,
Ca,
K
What induces the heart to release ANP?
distention of the atrial chamber (i.e., high blood volume)
How does ANF/ANP affect the body?
it stimulates the kidneys to eliminate Na and H2O.
The amount of [actin / myosin / tropomyosin] is the same in both smooth and skeletal muscles.
actin; and
tropomyosin
What are the 2 types of ossification?
- Endochondral;
- Intramembraneous
What is intramembraneous ossification?
the condensation of mesenchymal tissue into intramembraneous bone
What is endochondral ossification?
the indirect conversion of an intermediate cartilage model into endochondral bone
The holes, in bones, which are created by osteoclasts are called:
Howship’s lacunae
The nonspecific immune system is AKA the ____ immune system.
innate
The immune system can be divided into the ____ immunity and ______ immunity.
- innate / nonspecific
- acquired / adaptive
What is interferon?
a protein that prevents viral replication and dispersion
Is interferon part of innate immunity or adaptive immunity?
innate
Which cells are part of innate immunity?
macrophage;
mast cells;
granulocytes (neutrophils, eosinophils, and basophils);
dendritic cells;
NK cells
Which cell(s) are part of adaptive immunity?
B-cell;
T-cell
What are the 4 deviations / exceptions from Mendelian genetics?
- incomplete dominance
- codominance
- penetrance and expressivity
- inherited disorders
What is the numerical ratio that we see with (Mendelian) monohybrid crosses?
3 : 1
What is the ratio that we see with Mendelian dihybrid crosses?
9 : 3 : 3 : 1
What is the ratio that we see with incomplete dominance?
1 : 2 : 1
dominant : mixed : recessive
In genetics, what does penetrance mean?
Penetrance of a genotype is the # of ppl in a population carrying an allele, who actually express that allele’s phenotype.
In genetics, what is expressivity?
the varying severity of the expression of the phenotype (eg, disease symptoms), among ppl who have the same genotype
The ovulation period lasts about ___ days
24 hours
Which hormone(s)/neurotransmitter(s) can ↑↑ blood glucose levels?
- ACTH
- cortisol
- norepi / epinephrine
- glucagon
- growth hormone
- thyroxine
The 2 main tasks of the colon are:
- water reabsorption;
- K+ secretion
The fcn of aldosterone:
reabsorb Na and H2O
What organ(s) does aldosterone target?
Distal convoluted tubule; and
Collecting duct;
Large intestine / Colon
What is reabsorbed in the Proximal Convoluted Tubule?
The
- glucose
- ions
- H2O
- almost all the amino acids
which enter the nephron
- What is reabsorbed in the glomerulus?
- What is reabsorbed in the Bowman’s capsule?
nothing
ADH (and its analogs) stimulate the production of _____ in the nephron’s collecting ducts.
aquaporin channels
Aquaporins in the kidney allow for the :
reabsorption of H2O during the concentration of urine
Aldosterone is produced by the adrenals in response to:
↑↑ potassium levels;
OR
↓↓ Na levels
The mnemonic for the path the sperm takes until ejaculation:
SEVEN UP:
Seminiferous tubules;
Epididymis;
Vas def;
Ejaculatory Duct;
[nothing]
Urethra;
Penis
Which neurotransmitter(s) or hormone(s) can stimulate the parietal/oxyntic cells to secrete HCl:
acetylcholine
gastrin
histamine
S-cells are found in the ____. They secrete ____.
- duodenum;
- secretin
What does secretin do?
it’s an antacid that neutralizes duodenal contents
The ductus arteriosus shunts blood from the ____ to the ____.
pulmonary artery;
aorta
Which sites on the nephron can allow for water to pass through?
- PCT (reabsorbs 2/3 of all water in the nephron)
- descending loop (passive reabsorption)
- DCT (*ONLY *when stimulated by aldosterone)
- Collecting Duct (ONLY when stimulated by ADH)
When does DCT reabsorb water?
when stimulated by aldosterone
When does the nephron’s collecting tubule reabsorb H2O?
When stimulated by ADH
What effect does secretin have in the body? What does it target?
stimulates the pancreas to release bicarbonate
In nephrology, what does “filter”, “secrete”, and “reabsorb” mean?
filtered: passively pushed from blood to urine
secreted: actively pushed out from blood to urine
reabsorbed: pulled from urine back into blood.
Where in the nephron is glucose reabsorbed?
PC Tubule
What is the difference between proteins made by free ribosomes versus proteins made by Rough ER?
free ribosomes made proteins needed within the cell.
Rough ER ribosomes make proteins that will leave the cell.
The macula densa is a receptor that is stimulated to release ____ when it detects:
- renin
- low Na levels entering the distal nephron
The most selective part of the kidney’s filtration barrier is the ______ , which has ______ charge at physiological pH.
- basement membrane;
- negative
B/c the basement membrane of the kidney’s filtration barrier is negatively charged, only positively-charged and neutral particles will enter the _____.
nephron
ADH acts as receptors of the _____.
collecting tubule or collecting duct
Approx. 10 percent of the filtered ____ and 25 percent of the filtered ______ are reabsorbed by the loop of Henle.
- water;
- Na and Cl
Normally, the descending loop of Henle is permeable to ____ and is impermeable to _____.
water;
ions
Normally, the ascending loop of Henle is impermeable to ____ but allows the transport of _____.
- water;
- Na, K, and Cl
The first amino acid found in every eukaryotic protein:
methionine
The bicuspid (mitral) valve is located on the [right / left] side.
left
Function of the thymus is to:
replenish the T-cell population
T/F:
Both ventricles pump the same amount of blood.
tru
Central chemoreceptors respond to changes in [O2 / CO2 / both].
CO2 in arteries
The bronchial arteries, which feed the lungs, branch off of the ____.
aorta
The [Left / Right] lung has 2 lobes.
left
Platelets are synthesized by _____ cells.
megakaryocyte
Antibodies are made by a ____ cell, which is a specific type of B-cell.
plasma cell
A plasma cell is a specific type of ____ cell.
B-cell
B-cells are made in the _____.
bone marrow
T/F:
Cartilage is vascular tissue.
fals. cartilage is Avascular.
Cells of the ____ immune system are not specific, and will go after anything that appears foreign.
innate
A macrophage synthesizes an MHC [ one / two ] receptor, which is used to attach to a T-cell.
TWO
A T-cell can have 2 attachments to a macrophage.
The T-cell’s “t-cell receptor” will bind to the _____, while the T-cell’s ____ arm will bind to the macrophage’s ____ receptor.
- antigen presented by the macrophage
- CD4+ peptide arm
- MHC-2
The acquired/adaptive immune system has these subdivisions:
- cell - mediated;
- humoral
During muscle contraction, which bands and lines in a sarcomere will shorten? Which lengthen? Which remain the same?
UNALTERED: A band
SHORTENS: H and I bands
MOVES CLOSER: Z line
See chart on Question # 792 on page 277 of EK Bio 1001.
______ cells synthesizes muscle tissue.
Fibroblasts
Name the thin myofilaments.
F-actin;
tropomyosin; and
Troponin C
T-tubules are found in _____ cells.
skeletal muscle; and
cardiac muscle
The first heart sound is actually made by the closing of the :
mitral and tricuspid valves
The 2nd heart sound is actually caused by:
the closing of the aortic semilunar and pulmonary semilunar valves
Which hormone(s) stimulate the kidney to reabsorb Na?
aldosterone
[ADH only reabsorbs water.]
In cardiac muscle cells, gap junctions are called _____.
intercalated discs
The 5 assumptions of the Hardy-Weinberg equilibrium are:
- infinitely large population
- random mating (free love!)
- No mutations (NO TMNJ)
- No migration (xenophobia)
- No natural selection (jerry falwell)
MCAT Rules for X-linked Recessive Inheritance are:
- Disease more common in males
- Males with the mutant gene WILL get the disease
- Disease can skip generations
- If mother is a heterozygous carrier, her kids have **50% chance of getting **the disease
- Males with disease will give it to all of his **daughters **
- Males CANNOT pass it to their sons.
See # 900, page 290 of EK BIo 1001
The MCAT Rules for Autosomal Recessive Inheritance:
- 2 heterozygous (i.e., disease-free) parents can have a child with the disease
- Every time 2 heterozygous carrier parents mate:
- 25 % chance of having homozygous disease-free normal child
- 25 % risk of having homozygous child with disease
- 50 % chance of having a heterozygous disease-free kid who is a carrier
- Half of all kids appear to be disease-free
See Question # 905, page 210 of EK Bio 1001
The most common blood type :
O +
(oh positive)
What is pleiotropism?
When the alteration of one gene results in changing many, seemingly unrelated phenotypes.
E.g., mutation of 1 gene is pleiotropic if it alters development of heart, bone, and inner ears
What is polygenism?
A phenotype/trait is polygenic if it is influenced by many different genes.
E.g., height is polygenic b/c it relies on genes for growth factors, receptors, hormones, bone deposition, muscle development, energy utilization, etc.
What is epistasis?
A situation where the expression of alleles for one particular gene, depends on a different gene
E.g, a gene for curly hair cannot be expressed if a different gene causes baldness.
If an individual’s blood becomes hypotonic with respect to the (kidney) filtrate, would ADH secretion increase or decrease?
↓↓
The reabsorption of water from the kidney filtrate ↑↑ as the concentration of the interstitial fluid [increases / decreases].
increases
Interstitial fluid is [hypo- / hyper-]tonic to kidney filtrate.
hypERtonic
Kidney filtrate is [hypo- / hyper-]tonic to interstitial fluid.
hypOtonic
Fatty acids can be converted into glucose via Gluconeogenesis, HOWEVER:
Only ODD-chained fatty acids (i.e., odd number of Carbons) can.
In fetal blood circulation, where is the fetal blood oxygenated?
placenta
How many shunts exist in fetal blood circulation?
3
A fetus’ umbilical vein carries oxygenated blood from the _____ to the ____.
placenta;
inf vena cava
A fetus’ umbilical vein carries **[deoxygenated / oxygenated]** blood.
oxygenated
The ductus venosus connects the ____ with the ____.
umbilical vein
inf vena cava
The ductus arteriosus connects the ____ with the ____.
pulmonary artery;
aorta
What triggers the inhibition of gastrin’s secretion?
when chyme reaches a pH of 3 and moves into the duodenum
What are the types of dead spaces in the body?
anatomical dead space; and
alveolar
Anatomical dead space refers to:
air that remains in the mouth and trachea after inspiraton, and thus will not contact alveoli
Alveolar dead space refers to:
alveoli that contact air, but do not do any gas exchange
What is NF-κB?
a protein complex that controls transcription of DNA.
What can cause the oxygen dissociation curve to shift to the left?
- ↓↓ the partial pressure of CO2
- ↑↑ the pH
- ↓↓ the temperature
What is the Bohr effect?
the shifting of the oxygen dissociation curve to the RIGHT
What shape does a normal oxygen dissociation curve have?
sigmoidal
How does fetal oxygen dissociation curve differ from an adult’s oxygen dissociation curve?
Fetal hemoglobin has a greater affinity for O2 than adult hemoglobin, so the fetal curve is shifted to the left of an adult’s curve.
T/F:
Lymphatic vessels have smooth muscle.
fals
Lymph rejoins the blood circulation where the thoracic duct joins with the _____.
brachiocephalic vein
How do lymphatic vessels differ from blood vessels?
lymph vessels lack:
- smooth muscle
- tight jcns between the endothelial cells
What is special/important about the fovea of the eye?
it contains the greatest concentration of cones in the eye, & thus has the sharpest vision
List the Starling forces.
- capillary hydrostatic pressure (Pc)
- oncotic pressure (AKA colloid osmotic pressure) from blood plasma proteins (πc)
- hydrostatic pressure of the interstitial fluid (Pi)
- oncotic pressure of the interstitial fluid’s proteins (πi)
When talking about circulation, what does Pc stand for?
capillary’s hydrostatic pressure
When talking about circulation, what does πc stand for?
oncotic pressure of plasma proteins
When talking about circulation, what does P<strong>i</strong>stand for?
hydrostatic pressure of the interstitial fluid
The effect of ANP on the body is the exact opposite of this hormone(s):
aldosterone
Renin is secreted by juxtaglomerular cells, in response to:
- A ↓↓ in arterial blood pressure as detected by baroreceptors (pressure-sensitive cells).
- A ↓↓ in sodium chloride levels in the ultrafiltrate of the nephron. (This flow is measured by the macula densa of the juxtaglomerular apparatus.)
- Sympathetic nervous system activity, which also controls blood pressure (acting through the ß - 1 adrenergic receptors).
Which specific type of cell lines the Bowman’s space or Bowman’s capsule which shelters the glomerulus?
simple squamous epithelium
Define glomerular filtration rate:
- the rate at which liquid (and dissolved compounds) are pushed out from the glomerulus capillaries, into the kidney’s tubules.
- from blood to urine
Define renal corpuscle:
- part of the nephron
- renal corpuscle consists of: Bowman’s capsule + glomerulus
What does Tm stand for? I.e., what is the full term?
tubular transport maximum of any given substance
What is the tubular transport maximum?
the highest rate at which a given substance can be reabsorbed by the kidney
What force causes the filtration of liquid from the glomerulus, to the Bowman’s capsule?
blood pressure
(filtration is passive)
Ducklings will follow any large object they encounter during a critical period after hatching. This type of behavior is called:
imprinting
Is ammonia a Lewis acid, or is it a Lewis base?
Lewis base!
The optimal operating pH of trypsin is:
8
Trypsin does its job inside the [stomach/duodenum].
duodenum
T/F:
Mitochondrial genes are inherited in a Mendelian pattern of inheritance.
Fals.
Mitochondrial genes are passed by moms to all their sons and daughters.
Microfilaments are actually [actin / myosin / neither] filaments.
actin
Which has a greater probability of hydrogen bonding:
carboxylic acids, or alcohols?
carboxylic acid
Proteins are synthesized by starting from the [amino / carboxy]-terminal.
amino-terminal
In mammals, lipid-soluble toxins are metabolized by membrane-bound heme proteins called ____.
cytochrome P-450
In Michaelis-Menten kinetics, which of these is the Vmax is dependent on:
- total enzyme concentration
- substrate concentration
- the concentration of inhibitor that reversibly binds to the enzyme’s active site
Vmax is dependent on total enzyme concentration
In Michaelis-Menten kinetics, what fraction of active sites of the enyme are filled by substrate when [S] = 2*Km??
2/3
A more popular name for prolactin inhibitory factor is ___.
dopamine
