Bio/Biochem Missed Questions Flashcards
What does gastrin do?
hormone made by G-cells of the stomach that induces parietal cells to secrete HCl
What technique is used to measure RNA-level expression?
qRT-PCR
1. RNA extracted
2. reverse transcriptase converts RNA into cDNA
3. amplify cDNA using DNA polymerase
What is a nucleoside?
ribose or deoxyribose connected to purine or pyrimidine via B-glycosidic linkage
- no phosphate group
What do plasma cells, eosinophils, and neutrophils do?
plasma: differentiated B lymphocytes that create antibodies key in adaptive immunity
eosinophils: type of granulocyte involved in immune response against parasites and allergic reactions in innate immunity
neutrophils: most abundant WBC, first responders to bacteria and fungal infections in innate immunity
- phagocytosis
What does a protease do? lipase? amylase? sucrase?
protease: cleaves peptide bonds by hydrolysis
lipase: hydrolysis of fats
amylase: starch into sugars
sucrase: sucrose into fructose (5) and glucose (6)
Give me the Hardy-Weinberg Equation.
p+q = 1
p^2 + 2pq + q^2 = 1
What hormone promotes fatty acid breakdown?
growth hormone: release of FA from adipose tissue into bloodstream for energy production
What is happening in the stationary phase of bacterial growth?
reduction of resources slows reproduction rate to the point it equals the death rate
What does hCG do?
replaced by the placenta after the 1st trimester; thickens uterine lining, stops menstruation, stimulates progesterone production from the corpus luteum and maintains it, supports implantation
used to detect pregnancy
Which stage of menstruation is most similar to the state induced by an estrogen agonist?
follicular phase: causes growth in the endometrium via steady increase of estrogen that causes spike in LH and FSH
What describes vesicle traffic in the cell?
ER–> Golgi in anterograde transport
Golgi–>ER in retrograde transport
What are major differences between the somatic and autonomic nervous system?
somatic motor neurons directly connect from the spinal cord to the muscle without synapsing
ANS uses two neurons in series (pre- + postganglionic neurons) to relay messages from the spinal cord to target tissue
- only the ANS uses norepinephrine
What is recombination frequency? How does it relate to linkage?
likelihood two alleles are separated during crossing over is proportional to the distance between them
close to 0% = tightly linked genes
close to 50% = weakly linked genes
What does the seminal fluid contain after a vasectomy?
a normal pH, no sperm, and normal fructose count
– relatively alkaline to survive acidity of female reproductive tract
What structure can span the length of the axon in order to allow movement of molecules from the soma to the nerve terminal?
microtubules = highways for intracellular transport: motor proteins carry vesicles and organelles through the cell
microfilaments: actin; cell movement
intermediate filaments: anchor organelles
What happens in multiple sclerosis?
body’s immune system causes demyelination, replaces it with scar tissue
- nerve damage, brain shrinkage
What do the alar and basal plate form into?
alar: afferent, sensory neurons
- disorder = lack of sensation
basal: motor function
- disorder = quadriplegia
What happens when the total body water is high?
increase flow through the thoracic duct: circulatory system carries more fluid around the body and into tissues, from which the lymphatic system picks it up and returns it into circulation via the thoracic duct
secrete ANP, reduce ADH and aldosterone to excrete more water
What process in the thymus serves to prevent autoimmune reactions?
negative selection: causes apoptosis in cells that are self-reactive
positive selection is for eliminating T-cells that can’t bind to MHC properly
Which cell is most closely related to macrophages?
neutrophils: both come from granulocyte progenitor derived from myeloid stem cell
Describe the splits in hematopoiesis.
stem cell splits into lymphoid and myeloid
1) lymphoid = T-cells + B-cells (plasma cells)
2) myeloid = granulocytes (dendritic + macrophage), eosinophil, basophil (mast cell), platelets, erythrocyte
Where are peptide and steroid hormones stored?
peptide: secretory vesicles called granules
steroid: not stored anywhere because they are nonpolar and small, so they are synthesized when needed and can pass through lipid membranes
What are the ketogenic and glucogenic amino acids?
ketogenic: broken down into acetyl-CoA, which is a precursor for ketone body synthesis or can be used in the CAC for energy, bypassing PDH
- CANNOT contribute to glucose production
- leucine, lysine
glucogenic amino acids: broken down into pyruvate
- can be used in gluconeogenesis to produce glucose
- alanine, arginine, aspartate, glutamine, hisitdine, methionine, proline, serine, valine
both: isoleucine, phenylalanine, threonine, tryptophane, tyrosine
What atoms are involved in the cyclization of fructose to its pyranose form?
ketone functional group on carbon 2 and the hydroxyl group on carbon 6
- pyranose = 6 membered ring
- furanose = 5 membered ring, so carbon 5 attacks
How does underfeeding and overfeeding affect RQ?
RQ = carbon dioxide produced/oxygen consumed
underfeeding, increase in calories from lipids, lower RQ
overfeeding, increase in glucose, high CO2 made, higher RQ
How are proteins conjugated into lipoproteins, glycoproteins, and nucleoproteins?
covalent bonding with lipid, carbohydrate, or nucleic acid prosthetic group
What does the blood in the pulmonary arteries have higher concentrations of compared to blood in the pulmonary veins?
pulmonary arteries: deoxygenated blood to the lungs
- high H+, low pH, high CO2
pulmonary veins: oxygenated blood to the heart
- low CO2, high O2, low HCO3-, high pH
How long are sleep cycles? When is dreaming most likely to occur?
NREM (1-4) and REM lasts 90 minutes
- REM increases throughout the night
Most likely to dream during REM in the last sleep cycle closest to waking
What is the difference between internal and external validity?
internal: causality; if a change in the independent variable is really causing a change in the dependent variable
- increases when an experiment becomes more tightly controlled
- decreases when experiment becomes more like the real world and there are confounding variables
external: generalizability; if the observed relationship applies to other situations
- increases when experiment becomes more like the real world
- decreases when the experiment becomes more tightly controlled
What are the principles of training a new behavior in operant conditioning?
1) increase motivational state = deprive of a desirable stimulus (food)
2) shaping: rewarding successive approximations of desirable behavior
3) continuous reinforcement: rewarding desirable behavior
What does the spleen do?
filters the blood; destroys pathogens and damaged RBCs; immune response mounted by lymphocytes
ex) bacteria is circulated through lymph are removed in lymph nodes and bacteria in blood removed by the spleen
A certain eukaryotic species is triploid and has 24 total chromosomes. What is a feature of this species?
inability of some chromosomes to form homologous pairs during meiosis
- triploid species produce gametes with three copies of each chromosome
- STERILE
What is the Sapir-Whorf hypothesis / linguistic relativity?
language influences our perception and cognition
- stronger version = language CONTROLS perception and cognition
What is the Young-Helmholtz theory / trichromatic theory?
all the colors we see are result of combined activity of three types of photoreceptors
- short (blue), medium (green), and long (red) wavelengths
What would a patient with a lesion in the right primary visual cortex lose?
the left visual field is processed by the right cortex, so she would not be able to see anything to the far left of her central fixation point
What are the parvo and magno pathways of vision?
parvo: retina to ventral (lower) layers of the LGN
magno: retina to dorsal (upper) layer of LGN
color and motion are processed simultaneously via these two pathways
What is the difference between longitudinal, cross-sectional, case-control studies?
longitudinal: data gathered at multiple time points; assess risk factors or outcomes
cross-sectional: data gathered at one point in time; can determine prevalence of an outcome in a population
case-control: data gathered from individuals with the condition of interest compared to controls
If a patient has elevated kidney function, how should you change the dose of an antibiotic?
increase: antibiotic secreted at an elevated rate
What is the result of overactivity of beta cells in the pancreas?
increased levels of insulin causes:
1) triglyceride uptake by adipocytes
2) hypoglycemia
3) fatty acid synthesis in liver
Why would a culture of epinephrine not demonstrate a noticeable effect on cell metabolism?
require thyroid hormone to have a strong effect by increasing the number of epinephrine receptors on target cells
Why can’t muscle cells release glucose into the bloodstream?
they contain glycogen phosphorylase to activate glycogenolysis, but do not have glucose-6-phosphatase that hepatocytes have to convert it to glucose
Why is it a bad idea to eat a ton of carbs right before you run a marathon?
large amounts of glucose would release insulin which promotes lipid synthesis and prevents lipolysis, preventing fatty acid mobilization = main energy source for extended exercise
Which pathogen is not affected by CD4+ T-cell response?
virus: targeted by CD8+ T-cells after being activated by CD4 + T-cells
bacteria, fungus, and parasites are mostly extracellular
Which cell type does not present antigen in conjunction with MHC class II molecules?
natural killer cells
- induce apoptosis in virally infected cells by detecting decrease in MHC I expression
B-cells, dendritic cells, and macrophages all present antigens
What is the pathway for galactose to enter glycolysis?
galactose (+galactokinase, ATP) –>galactose-1-P (+uridyl transferase) –>glucose-1-P (+mutase)–>glucose-6-P –> glycolysis
What degrades ubiquinated structures inside the cell? What are the other digestive organelles?
Proteasomes degrade ubiquinated structures
Lysosomes: degrade cellular structures (damaged organelles) and macromolecules (proteins, nucleic acids, carbs)
Peroxisome: break down fatty acids and reduce ROS
What is the difference between juxtacrine and paracrine signaling?
juxtacrine: direct contact between two directly adjacent cells; ligand on one cell binds to a receptor on the other; there is NO secretion
paracrine: secretion of signaling molecules over a short distance
What amino acids are ketogenic but NOT glucogenic?
leucine and lysine
Where does menstruation occur on the plot of hormones?
periods occur during the point of lowest LH and FSH secretion
What stage of embryogenesis is a freshly fertilized egg?
zygote: two haploid gametes (sperm + ovum) fusing to form a diploid cell
morula: zygote undergoes few rounds of cellular division, 16-32 cells
blastula: inner cell mass and trophoblast
implantation –> gastrula: three germ layers
neuralation: ectoderm into neural plate
How can killed cells still induce development?
killed cells cannot participate in metabolism, but they still contain the inducer chemicals that can be released upon their death
Which cell type produces antibodies?
B cells
What results from long-term damage to the cilia of the respiratory epithelia from smoking?
cilia move mucus and trapped particles from lungs
increased infection by pathogens, increased obstructive lung disease, decreased cough reflex
What are the properties of cartilage that make RA damage irreversible?
avascularity (cannot be repaired easily from lack of materials and energy needed for cell replication and tissue repair)
What determines the strength of DNA binding?
the amount of CG content (3 H bonds) and the length
How do you get deltaG from E?
deltaG = -nFE
deltaG = -RTlnK
when K<1, lnK is NEGATIVE
Where is proline most likely to be found in a cytosolic protein?
turns between B-pleated sheets
Individuals that display a homozygous recessive genotype typically do not survive early childhood. What accounts for the continued presence of that allele in the gene pool?
heterozygote advantage: carriers of the recessive allele have a survival advantage
What is hybrid vigor?
breeding two different species; offspring are generally infertile
What responds to parasitic infection first?
eosinophils: release histamine which helps drive inflammatory response
- leaky blood vessels for macrophages + neutrophils to enter and start digesting
What happens during a pneumothorax?
intrapleural pressure increases and the diaphragm is pushed downward
- differential pressure is dissipated
A deficiency in which enzyme would cause the inability to effectively produce nucleotides?
glucose-6-P dehydrogenase
- need pentoses; this turns glucose into ribose-5-phosphate
Pentose phosphate pathway
What vitamin depends on the exocrine pancreas for absorption?
K: exocrine pancreas secretes lipase which digests fat-soluble vitamins to be absorbed
A,D,E,K
What is an irreversible inhibitor?
permanent loss of enzymatic activity; doesn’t wear off (7 days)
ex) aspirin binds irreversibly, so new enzyme has to be synthesized
What conditions would impair de novo synthesis of fatty acids?
1) mutations in the citrate shuttle (carries acetyl-CoA into the cytoplasm)
2) increased oxidative stress, decreasing NADPH (reducing agent)
3) biotin deficiency: co-factor for acetyl-CoA carboxylase (first step to convert to malonyl-CoA)
What is the appendicular vs. axial skeleton?
axial consists of skull, vertebral column, rib cage, and hyoid bone
remainder is appendicular
- 100/206 are in hands and feet
Where do humans have cartilage?
intervertebral discs, joints, walls of larynx and trachea, ears, nose
What is true regarding the loop of Henle’s descending and ascending limb?
descending limb is a CONCENTRATING segment because it is only permeable to water
ascending limb is a diluting segment because it is only permeable to solutes
What happens in curare poisoning (binds irreversibly to ACh receptors in NMJ)?
depolarization of the sarcolemma is prevented, causing muscle relaxation
A developing T lymphocyte is LEAST likely to be prevented from entering circulation and becoming activated if its cell-surface receptor recognizes:
self-MHC but not self-antigen
- cells that can’t recognize MHC undergo apoptosis (positive selection)
- cells that attack self-antigens are killed (negative selection)
Where is the lesion is a patient presents with blindness in the superior right quarter of his visual field?
left hemisphere on the lower bank of the sulcus
- visual fields are processed by the contralateral side of the brain
How does hydrostatic and oncotic pressure change across capillaries?
at the start of the capillaries, blood pressure is high and therefore hydrostatic pressure is high to drive fluids and nutrients across the capillaries
there is little fluid at the venous end, increasing the concentration of albumin which increases oncotic pressure to draw fluid back into bloodstream
What is the role of albumin?
transports lipid hormones and fatty acids through the bloodstream, helps with regulation of fluids through oncotic pressure
low levels when there is liver failure
Which type of hormone directly stimulates transcription in the nucleus?
steroid: nonpolar and small, so they can pass through the membrane and directly stimulate transcription
During pregnancy, where is hCG produced and why?
in the placenta to thicken uterus, stimulate corpus luteum to produce progesterone, stops menstruation
hCG levels decline by second trimester because placenta is big enough to secrete estrogen + progesterone itself
What is true of gasses in the alveoli?
the partial pressure of oxygen is higher in the alveoli than in the alveolar capillaries to ensure diffusion into the bloodstream
the partial pressure of carbon dioxide is greater in the capillaries than the alveoli so it diffuses out of the blood
What is something eukaryotes have to regulate gene expression that prokaryotes don’t have?
histones
What is true of all promoters in eukaryotes?
TATA boxes to which RNA polymerase and secondary transcription factors are recruited by the primary transcription factor
Where is secretin expressed and what does it do?
decrease in the pH of luminal contents causes the duodenum to release secretin (neutralizes pH) to stimulate the secretion of pancreatic enzymes (lipase, amylase)
- allows proper enzymatic function
What is the key enzyme in the PPP?
glucose-6-phosphate dehydrogenase
- first step that produces NADPH
How do you read a gel electrophoresis of DNA fragments?
bottom to top (+ to -) is 5’ to 3’
What are the 5 types of bones?
1) Long bones: longer than they are wide
- femur (thigh bone)
- humerus (upper arm bone).
2) Short bones: cube-shaped bones with similar length and width
- wrist
- ankle
3) Flat bones: thin, flattened bones
- skull bones, rib cage, shoulder blades
4) Irregular bones: bones with complex shapes that don’t fit into the other categories
- vertebrae and facial bones.
5) Sesamoid bones: small, round bones embedded within tendons
- patella
What is an epimer, anomer, and enantiomer?
epimer: differs at one carbon
anomer: differs at C-1
enantiomer: differs at every carbon
How are neuronal tracts organized in the spinal cord?
CNS group of axons = tracts
afferent sensory neurons carry information to the brain in the dorsal white matter (myelinated axons)
efferent motor neurons carry information from the brain to the periphery in the ventral white matter (myelinated axons)
What is the difference between kinesin and dynein?
kinesin: moves intracellular cargo along microtubules in anterograde axonal transport (away from nucleus and towards distal site)
dynein: retrograde axonal transport of intracellular cargo (distal sites towards nucleus)
What would cause an embryo to implant in a location other than the uterine lining?
reduced number of fallopian cilia: help propel the fertilized oocyte toward the uterus for implantation
What does the Hill coefficient represent?
0< 1 : negative cooperativity
1: independent binding
> 1: positive cooperativity
What is the shape of MM kinetics graph for a changing concentration of cofactor and substrate?
hyperbolic with no cooperativity
positive cooperativity = sigmoidal
What does increase temperature trigger in addition to sweating?
vasodilation of the surface capillaries
Which layer of the skin is responsible for keeping it relatively impermeable to water?
stratum corneum: outermost layer composed of many layers of keratinocytes
Which steps of the citric acid cycle produce electron carriers? Which step produces GTP?
1) isocitrate to alpha-ketglutarate: 1 NADH
2) alpha-ketglutarate to succinyl-CoA: 1 NADH
3) succinate to fumarate: 1 FADH2
4) malate to oxaloacetate: 1 NADH
succinyl-CoA to succinate: 1 GTP
What happens to initiate apoptosis?
oxidative stress + DNA damage; mitochondrial membrane is permeabilized in response
increase cystolic Cyt C which induces proteolysis by activating caspases
How many NADH and FADH2 is produced per one pyruvate?
4 NADH and 1 FADH2
Which muscle types are striated?
skeletal and cardiac
- contain sarcomeres
Which muscle cells have gap junctions?
cardiac and smooth
What is a reducing sugar?
free, anomeric carbon that can be oxidized
How does an enzyme affect a reaction already at equilibrium?
it does not affect its rate; net rate remains at 0
How do you get the M+ and M+2 peak on mass spec graphs?
M: molecular weight
M+: immediately after M peak
M+2: add two to the molecular weight
3:1 ratio indicates single chlorine
1:1 ratio indicates single bromine
Describe fetal blood flow.
1) Oxygenated blood from the placenta travels via the umbilical vein
2) Blood bypasses the liver through the ductus venosus entering the inferior vena cava (IVC)
3) Blood enters the right atrium (RA) and follows two main pathways:
1. Foramen ovale: Shunts oxygenated blood from the RA to the left atrium (LA) → left ventricle (LV)→ aorta → systemic circulation
2. Right ventricle (RV) path: Some blood enters the RV → pulmonary artery, but most bypasses the lungs via the ductus arteriosus → descending aorta → systemic circulation.
4) Deoxygenated blood returns via the umbilical arteries to the placenta for reoxygenation
What kind of chromatography should be used to separate something based on charge?
HPLC ~ ion exchange chromatography
What drives the fluid back into the capillary at the venule end?
hydrostatic pressure at the venule end is lower than the oncotic pressure
- oncotic pressure is constant along the capillary (albumin can’t cross)
In gluconeogenesis, pyruvate is converted to oxaloacetic acid and then to?
phosphoenolpyruvate
What is the difference between euchromatin and heterochromatin?
euchromatin: loosely wrapped chromatin for active transcription
- histones are acetylated to remove + charged ends
heterochromatin: densely packed chromatin
When do proteins start to denature?
optimal: 37 degrees celsius (body temperature)
most proteins denature above 45 degrees
greatly reduced maximal activity at 65 degrees
What effect would an iron deficiency have on respiration in RBCs?
no effect: RBCs lack mitochondria, so they rely on anaerobic respiration for energy
What enzyme is active under anaerobic conditions?
pyruvate dehydrogenase: reduces pyruvate to lactate and oxidizes NADH to NAD+
What DNA sequences are best recognized by restriction endonucleases?
palindromic DNA sequences: the 5’–>3’ direction is identical to the 3’–>5’ sequence of the other strand
- split it down the middle and see if they BP
How do you name terpenes?
hemiterpene: 1 isoprene unit, 5 carbons
monoterpenes: 2 isoprene units, 10 carbons
sesquiterpenes: 3 isoprene units, 15 carbons
diterpenes: 4 isoprene units, 20 carbons
What is the difference between red marrow and yellow marrow?
red: production site of RBCs, white blood cells, and platelets
yellow: fat, cartilage
What is passive immunity?
individual receives preformed antibodies from another source, rather than producing them themselves
- mother to fetus
What can you assume about data that is normally distributed?
all three measurements of central tendency (mean, median and mode) will be approximately equal
What is true about the cytoskeleton?
composed of microtubules and microfilaments, maintains cell’s shape, required for mitosis, important for cell mobility
What is brown fat?
keeps you warm when you get cold
Why does hyperthyroidism cause inability to thermoregulate?
elevated thyroid hormone increase metabolic rate and generates excess heat, raising body temperature, making them extra sensitive to heat because they already have excess heat to dissipate
What is the difference between posterior and anterior pituitary?
posterior: stores hormones synthesized in the hypothalamus
- ADH (Vasopressin), oxytocin
anterior: synthesizes hormones itself
- ACTH, TSH, GH, prolactin, FSH, LH
What supports the conclusion that brown eyes are the dominant trait in eye color?
two parents with brown eyes produce an offspring with blue eyes
What is the difference between sphingomyelins and glycospingolipids?
sphingomyelins: fatty acid backbone, phosphocholine (polar) head group
glycospingolipids: fatty acid backbone, have sugar (polar) head group
In an inducible operon, how does the inducer function as a positive controller?
it complexes with a repressor sitting on the operator, preventing DNA binding and allowing transcription to occur
Which of the following sugars contain B-glycosidic linkages?
cellulose, starch, fructose, lactose, maltose
cellulose and lactose
- fructose: monosaccharide
- maltose: glucose-glucose via alpha linkage
- starch + glycogen: alpha 1,4/1,6 linkages
The failure of “soft spots” of the skull to close within a few months after birth is a failure of:
intramembranous ossification: flat bones form in skull
What is endochondral ossification?
bone formation in the embryonic skeleton through childhood that is the gradual replacement of cartilage with bone tissue
Why is vancomycin ineffective against Gram-negative bacteria?
vancomycin is too large to reach its target
- Gram negative cells have porins that restrict the entry of large molecules
What is most likely a trait of cancer stem cells?
self renewal of undifferentiated stem cells
- generally multi or pluripotent
In prokaryotes, genes can exist as operons that are transcribed into a polycistronic mRNA, containing multiple genes in a single transcript. In eukaryotes, transcripts exist only as monocistronic mRNA containing a single gene. What fundamental genetic difference is responsible for this distinction?
in eukaryotes, each gene has its own transcription initiation site
What is the transmission mechanism of a disease where females transmit it to all their offspring + it’s cytoplasmic?
mitochondrial DNA: transmitted through a cytoplasmic component + maternally inherited from ova
What aspects separate single-crossover events from double-crossover events?
Single-crossover events affect only the ends of chromosome arms, while double-crossover events can affect segments in the middle of chromosome arms.
What happens if the enzyme that catalyzes the transformation of acyl-CoA into acyl-carnitine molecule to enter the mitochondrial matrix is faulty? What are the symptoms?
makes the first step of beta-oxidation faulty, so fatty acids can’t get into the mitochondria
muscle weakness (less energy), liver damage (build up of fat), and high levels of ammonia in the blood from increased protein metabolism, hypoglycemia (glucose as main source of energy)
A researcher analyzes a sample of unknown nucleic acid. After looking at only its nucleotide composition, he concludes that the sample is composed entirely of single-stranded DNA. Which of the following compositions most likely represents this sample?
anything without equal proportions of AT and GC (double stranded)
What is the difference between the two Hardy-Weinberg Equations?
p + q = 1
- allele frequency
ex) recessive autosomal allele is 1.2% ==> q = 0.012, p = 0.988
p2 + 2pq + q2 = 1
- genotype frequency
Those species that are capable of both sexual and asexual reproduction will typically prefer sexual reproduction because it:
creates more variation in the next generation, increasing fitness of the whole species
Positron Emission Tomography (PET) scans follow the movement of a radioactively-labeled compound throughout the body and are often used to detect metabolic activity in cancer cells relative to normal cells. The labeled compound is most likely:
glucose: cancer cells have very high rate of glycolysis relative to normal cells
Why can researchers use measurements of intracellular lactate levels (ILL) in cancer cells to assess efficacy of cancer drugs?
low ILL would indicate that glycolysis is significantly inhibited
- lactate is a product of fermentation: 2 pyruvate –> 2 ethanol or lactate when O2 is absent
What effects does cholesterol have on membrane fluidity at different temperatures?
high temperature: prevents membrane from becoming too fluid by restricting the movement of phospholipids
physiologic: increases membrane rigidity
low temperatures: prevents membrane from being too rigid by preventing phospholipids from packing too close together
Which of the following do NOT have proteins with a nuclear localization signal?
I. E. coli
II. Homo sapiens
III. Fungi
IV. Archaea
I & IV
bacteria and archaea do not have nuclei
fungi + eukaryotes have nuclei
What is the difference between analogous and homologous structures?
analogous: evolved independently to carry out the same function
ex) wing of bird and wing of bee
homologous: similar evolutionary history, even if the structures have different functions
ex) human arm, walrus flipper, bat wing
What are the steps of western blot?
1) gel electrophoresis
2) proteins in the gel are transferred to protein-binding membrane where they become immobilized
3) portions of the membrane to which protein was not transferred are blocked by protein-rich mixtures, preventing antibodies from nonspecifically binding
4) membrane incubated with antibodies that specifically bind to the protein of interest
5) fluorescence
What does isothermal titration calorimetry measure? Why do the peaks decrease over time on the plot?
measures heat of binding as increasing concentrations of ligand are titrated into a solution of protein
- each binding releases energy
- less available binding sites, less heat released
When does a phospholipid membrane have the most unsaturated fatty acid tails?
decreased fluidity at low temperatures, so increase in unsaturated fatty acids to restore fluidity (kinks)
Where are postganglionic neurons located?
outside the CNS in the PNS
- receive signals from preganglionic neurons in the brainstem and spinal cord and then send signals to target organs
