APK2105c exam 2 summer
which of the following is true regarding the first half of hyperpolarization?
cell more permeable to K+ in comparison to resting membrane potential
which of the following correctly pairs a tropic hormone with its respective regulated hormone?
follicle stimulating hormone (FSH) and estrogen
which molecule is most likely to travel through a plasma membrane via facilitated diffusion
glucose
if you were to pour a bunch of salt into the solution surrounding a cell then what would you say about the solution? (Q5)
its osmotic pressure is increasing
what enables intracellular potassium to stay elevated and sodium to stay low inside neurons? (Q7)
primary active transport
what type of transport involves a molecule being moved from low to high past the plasma membrane using ATP as the energy source? (Q5)
primary active transport
which of the following statements regarding osmosis are correct? 1. water moves from an area of low osmolarity to high osmolarity 2. water moves from area of low solute concentration to area of high solute concentration 3. a cell swells when submerged in a hyperosmotic solution 4. a red blood cell will shrink when submerged in a hypoosmotic solution
1 and 2
place following events in order: 1. the neurotransmitter inside the synaptic vesicles is released via exocytosis 2. the ligand-gated channels on the postsynaptic neuron open 3. the voltage gated calcium channels on the axon terminal button open 4. the neurotransmitter binds to the ligand-gated channels on the postsynaptic neuron
3, 1, 4, 2
if oxygen was not present, how would it affect the ETC
4th complex accumulates electrons as O2 would not be there to remove them
describe the ion concentrations associated with intracellular and extracellular fluid of a neuron
Higher [K+] inside, higher [Na+] outside
which of the following molecules/atoms would be able to diffuse through the plasma membrane without and integral protein?
None of the above
which refers to the period of time in which another action potential cannot be generated under any circumstance?
absolute refractory period
with regard to depolarization, which of the following occurs when any given region of the axon hits -55mv?
activation gates on the coltage gated sodium channels open
how does AP allow for exocytosis of neurotransmitters from the button?
allows for voltage gated Ca2+ channels to open in the button
which of the following is an example of simple diffusion
atmospheric oxygen passing through the plasma membrane
which part of the neuron passes information to another cell? (Q7)
axon terminal buttons
which of the following is true regarding absolute and/or relative refractory periods?
b. absolute refractory period requires the sodium channels to be reset between -60 and -70 mV before another AP can be generated
Why can't a neuron generate another AP during repolarization prior to the interior reaching between -60 to -70 mV
because inactivation gates on the voltage gated sodium channels are closed
regarding the answer to the previous question, why does this prevent another action potential from being generated
because inactivation gates will not open under any voltage
why does a non-polar molecule typically use simple diffusion? (Q5)
because of the core of plasma membrane is non-polar and will not reject it
why would benzodiazepines reduce anxiety?
by mimicking GABA and hyperpolarizing neurons
chemical driving force is also known as: (Q7)
diffusion gradient
How does water typically travel through plasma membrane?
diffusion through channels
what happens at the equilibrium potential? (Q7)
electrical and chemical driving forces are equal
what molecule is important for initiating the breakdown of glycogen?
epinephrine
t-cells release protein filled vesicles called cytokines in the ECF. what is this process called?
exocytosis
true or false: if a neuron's axon hillock at rest depolarizes by 10 mV, then a action potential will occur.
false
true or false: passive transport is against the gradient and requires ATP to function.
false
what type of stimulus involves a hormone stimulating tissue to release hormones? (Q6)
hormonal
the pancreas (beta cells) releases insulin when blood sugar rises. what type of stimulus is this? (Q6)
humoral
if someone is taking anabolic steroids, there will be a significant increase in testosterone. what would happen next?
hypothalamus will not release GnRH
neurons are more permeable to potassium than sodium, which results in more potassium leaving than sodium entering. what does this cause to happen? (Q7)
interior to become more negative due to loss of potassium ions
if the solution outside of a cell has the same osmolarity of the solution inside the cell then it is said to be: (Q5)
isosmotic
which of the following is generally true about GABA
it allows chloride into neurons
regarding the previous question, what influence would GABA have on a neuron?
it would make it harder for it to generate an action potential
which hormone is released under a neural stimulus? (Q6)
oxytocin
what is a function of the axon hillock in a neuron?
point of initiation of action potentials
which transport involves diffusion of Na+ ions past an integral protein so another molecule can move from low to high
secondary active transport
if there is a non-polar molecule that is a higher concentration outside the cell compared to the inside, what type of transport?
simple diffusion
which type of transport would you expect a non-polar molecule to use? (Q5)
simple diffusion
why is it dangerous for a cell to be in a highly hypo-osmotic solution?
the cell will fill with water and potentially burst
a fall (decrease) in the amount of estrogen in the blood will DIRECTLY result in: (Q6)
the hypothalamus releasing GnRH
why does the charge of an action potential never go above +30 mV and begin repolarizing from there?
the inactivation gates of Na+ channels close at +30mV AND the rate of potassium leaving the cell begins to be greater than Na+ entering
what is a synapse and what function does it serve?
the meeting of a neuron with another cell and allows for sharing of info
considering osmosis, what would you expect to happen within the image below? (Q5)
the water will move from left to right
what would cause pyruvate to accumulate in the mitochondria
too little NAD in the mitochondria
a hormone that stimulates the release of other hormones is referred to as a: (Q6)
tropic hormone