Question 1

Which of the following best explains why the resting membrane potential of a neuron is typically around $$-70\ \mathrm{mV}$$?

Accepted Answer

Because the concentration gradients of $$\mathrm{Na}^+$$ and $$\mathrm{K}^+$$ across the membrane and selective permeability to $$\mathrm{K}^+$$ create a negative interior.

Question 2

A peptide hormone binds to its receptor on the surface of a target cell. What is the most immediate intracellular event that follows?

Accepted Answer

A second messenger, such as $$cAMP$$, appears in the cytoplasm.

Question 3

Which of the following statements about peptide hormones is INCORRECT?

Accepted Answer

Peptide hormones are always found in the bloodstream bound to carrier proteins.

Question 4

Catecholamines, such as epinephrine and norepinephrine, are best classified as which type of molecule?

Accepted Answer

Amino acid-derived hormones synthesized from tyrosine.

Question 5

Which two factors determine the equilibrium potential for an ion across a cell membrane, as described by the Nernst equation?

Accepted Answer

The concentration gradient of the ion and its valence (charge).

Question 6

A patient is exposed to a toxin that blocks voltage-gated $$\mathrm{Ca}^{2+}$$ channels at the axon terminal. Which process will be directly impaired?

Accepted Answer

Exocytosis of neurotransmitter into the synaptic cleft.

Question 7

Which of the following best describes the role of ATP during skeletal muscle contraction?

Accepted Answer

ATP hydrolysis provides energy for the power stroke and detachment of myosin from actin.

Question 8

Which property of the action potential ensures that the signal travels in only one direction along an axon?

Accepted Answer

The refractory period, during which voltage-gated $$\mathrm{Na}^+$$ channels are inactivated.

Question 9

Why is myelin not continuous along the entire length of an axon?

Accepted Answer

To permit the generation of action potentials at the nodes of Ranvier, enabling saltatory conduction.

Question 10

A person is exposed to a drug that blocks all autonomic ganglia. Which of the following effects would most likely be observed?

Accepted Answer

Disruption of both sympathetic and parasympathetic regulation of target organs.

Question 11

Which of the following best describes the difference between the sympathetic and parasympathetic pathways in terms of neurotransmitters and receptors?

Accepted Answer

Sympathetic postganglionic neurons typically release norepinephrine onto adrenergic receptors, while parasympathetic postganglionic neurons release acetylcholine onto muscarinic receptors.

Question 12

Which of the following best defines 'driving force' for an ion across a membrane?

Accepted Answer

The difference between the membrane potential and the ion's equilibrium potential.

Question 13

Which of the following is an example of lateral inhibition and its importance in sensory perception?

Accepted Answer

Enhancing contrast at the edge of a touched object by inhibiting neighboring sensory neurons.

Question 14

Which event occurs immediately after acetylcholine (ACh) binds to nicotinic receptors on a skeletal muscle cell?

Accepted Answer

Voltage-gated $$\mathrm{Na}^+$$ channels open, leading to depolarization of the muscle membrane.

Question 15

Which of the following best describes spatial and temporal summation in neurons?

Accepted Answer

Spatial summation is the addition of multiple graded potentials from different locations; temporal summation is the addition of graded potentials from a single source over time.

Question 16

Which of the following is a function of the regulatory proteins in the thin filaments of skeletal muscle?

Accepted Answer

Troponin and tropomyosin regulate the binding of myosin to actin by covering or exposing binding sites.

Question 17

How does the inner ear code for pitch and amplitude of sound?

Accepted Answer

Pitch is coded by the location of hair cell activation along the basilar membrane; amplitude is coded by the frequency of action potentials.

Question 18

Which of the following best describes cerebral lateralization?

Accepted Answer

The specialization of certain functions to either the left or right hemisphere of the brain.

Question 19

Which of the following is a correct example of a sensory receptor and its function?

Accepted Answer

Photoreceptors in the retina detect light.

ANP Exam 2 Practice Questions – Step-by-Step Study Guidance

Study Guide - Practice Questions

Study Guide - Flashcards