BIOL 2160-Exam 3

A larger than threshold stimulus would result in:

a. more frequent action potentials

b. none of these

c. faster action potentials

d. larger action potentials

e. longer action potentials

a. More frequent action potentials

A stimulus that opens muscarinic acetylcholine receptors on the post-synaptic cell will generally result in the production of:

a. EPSP

b. IPSP

b. IPSP

Neurons do not have a resting membrane potential.(T/F)

False

An auto-immune disease that attacks myelin sheaths on ganglia will have a direct effect on which type of glial cell?

a. Schwann cells

b. Oligodendrocytes

Schwann cells

An EPSP arriving at a dendrite immediately after another EPSP arrives is an example of:

a. Spatial summation

b. Temporal Summation

Temporal Summation

An individual with a BMI above 35 is approximately ____ times as likely to develop Type 2 diabetes than an individual with a BMI below 25.

a. six

b. three

c. four

d. two

a. Six

An injection of atropine would result in:

a. No paralysis

b. Skeletal muscle paralysis

c. Both Skeletal and cardiac muscle paralysis

d. Cardiac muscle paralysis

a. No paralysis

Application of curare will prevent the production of:

a. EPSPs

b. IPSPs

a. EPSP's

At -50mv, during the falling phase of an action potential, which is larger?

a. K+ current

b. Na+ current

a. K+ current

At rest, voltage-gated Na+ channels are found in which conformation?

a. Closed (but capable of being opened)

b. Inactivated

c. Open

a. Closed (but capable of being opened)

At rest, which ion is the cell most permeable to?

a. NA+

b. K+

b. K+

Conductance affects driving force. (T/F)

False

Damaged beta cells in the pancreas would result in:

a. Hypoglycemia

b. Hyperglycemia

b. Hyperglycemia

During phase 3 of the action potential, the cell is:

a. More permeable to K+

b. More permeable to Na+

a. more permeable to K+

During the relative refractory period, voltage gated K+ channels are:

a. open

b. closed

a. Open

During the falling phase of the action potential voltage-gated Na+ channels will be:

a. Inactivated

b. Closed

c. Open

a.Inactivated

During the post-absorptive state, more cells metabolize:

a. Glucose

b. Aldehydes

c. Glycogen

d. Protein and Fats

d. Protein and Fats

During the relative refractory period, the cell is less permeable to:

a. Na+

b. K+

a. Na+

Exocytosis of synaptic vesicles is a direct results of which ion?

a. Na+

b. K+

c. Ca2+

c. Ca2+

High blood sugar will indirectly ______ the ph of the blood.

a. Lower

b. Raise

a. Lower

How does insulin lower blood sugar levels?

a. By causing downregulation of GLUT-4

b. By activating glucagon

c. By making cells more permeable to glucose

c. By making cells more permeable to glucose

Hyper-osmolar Non-ketotic coma is a result of ______ urination.

a. increased

b. decreased

a. increased

Decreased insulin production would result in _____ urine output.

a. increased

b. decreased

a. increased

Inter neurons are located in the peripheral nervous system. (T/F)

False

Ion channels do which of the following to membrane resistance?

a. increase

b. decrease

b. decrease

it is possible to produce an action potential during the absolute refractory period with a large enough stimulus. (T/F)

False

Movement of calcium from the sytosol into the Endoplasmic Reticulum (ER) is an active process. (T/F)

True

Neurotransmitters are used where?

a. chemical synapses only

b. Both electrical and chemical synapses only

c. Electrical synapses only

a. Chemical synapses only

Skeletal muscle contraction is under control of:

a. parasympathetic nervous system

b. somatic nervous system

c. afferent nervous system

d. sympathetic nervous system

b. Somatic nervous system

The membrane potential moving from -50mv to -70mv is an example of:

a. Repolarization

b. Hyperpolarization

c. Depolarization

a. Repolarization

The nicotine acetyloline receptor is more permeable to Na+ than it is to K+. (T/F)

False

The permeability of the cell to K+ is highest during:

a. At rest

b. The falling phase

c. The rising phase

d. The undershoot

b. The falling phase

The permiability of the cell to Na+ will be highest at membrane potentials more ______ than -70mv.

a. positive

b. negative

a. Positive

The undershoot phase of the action potential is due to:

a. Slow closing of voltage-gated K+ channels

b. Slow opening voltage-gated K+ channels

a. Slow closing of voltage-gated K+ channels

Vision is an example of a ______ sense.

a. visceral

b. somatic

c. special

c. Special

What causes the transition from the rising phase to the falling phase of the action potential?

a. Inactivation of voltage-gated Na+ channels

b. None of these

c. Opening of voltage-gated K+ channels

d. Both of these

d. Both of these

What percentage of total diabetes cases are juvenile-onset?

a. 5-10%

b. 90-95%

a. 5-10%

What type of channel is opened by the G-protein in a muscarinic receptor?

a. Na+ channel

b. K+ channel

b. K+ channel

Where is resistance the highest?

a. membrane

b. extracellular solution

c. Intracellular solution

a. Membrane

Where will commissures be found?

a. PNS

b. CNS

b. CNS

Which glial cells produce cerebrospinal fluid (CSF)?

a. Astrocytes

b. Microglia

c. Schwann Cells

d. Ependymal cells

d. Ependymal cells

Which hormone is most likely to stimulate glycogenesis?

a. Insulin

b. Glucagon

a. Insulin

Which is more likely to occur during negative energy balance?

a. Glycogenolysis

b. Glycogenesis

a. Glycogenolysis

Which of following is a catabolic hormone?

a. Glucagon

b. Insulin

a.Glucagon

Which of the following might describe an IDSP?

a. None of these

b. Change in membrane potential from -70mv to -90mv

c. Change in membrane potential from -90mv to -70mv

b. Change in membrane potential from -70mv to -90mv

Which of the following will NOT turn off synaptic transmission?

a. Pumping Ca2+ out of the cell

b. Pumping Ca2+ into the mitochondria

c. Pumping Ca2+ into the ER

d. Pumping Ca2+ into the cytosol

e. none of these

d. Pumping Ca2+ into the cytosol

Which of these is uni-directional?

a. Both

b. Neither

c. Chemical Syapses

d. Electrical Syapses

c. Chemical Syapses

Which type of summation involves inputs arriving at the postsynaptic cell simultaneously?

a. Spatial

b. Temporal

a. Spatial

Why is a stronger stimulus needed to invoke an action potential during the relative refractory period?

a. Because the membrane is more permeable to Na+ than it is to K+

b. Because the membrane is more permeable to K+ than it is to Na+

b. Because the membrane is more permeable to K+ than it is to Na+

Why is propagation in a myelinated axon faster than unmyelinated?

a. Because myelin has very high resistance

b. Because nodes of Ranvier have no ion channels

c. All of these

d. Because ion channels in myelin are not permeable to K+

e. Because the action potential jumps from one syretch of myelin to another

a. Because myelin has very high resistance