Question 1

According to Fick’s Law of Diffusion, which adaptation would most effectively increase the rate of oxygen diffusion across a respiratory membrane in a fish?

Accepted Answer

Increasing the difference in partial pressure of oxygen across the membrane

Question 2

Which of the following best explains why countercurrent flow in fish gills maximizes oxygen uptake?

Accepted Answer

It ensures that the partial pressure gradient for oxygen is maintained along the entire length of the gill.

Question 3

A patient is exposed to high levels of carbon dioxide. Which of the following best describes how hemoglobin’s affinity for oxygen will change, and what is this effect called?

Accepted Answer

Affinity decreases; this is the Bohr shift.

Question 4

Which equation correctly represents Fick’s Law of Diffusion as it applies to gas exchange?

Accepted Answer

$$J = D \frac{A (P_2$ - P_1$)}{d}$$

Question 5

Which of the following best describes how the contraction of the diaphragm powers inhalation in mammals?

Accepted Answer

The diaphragm contracts, increasing thoracic cavity volume and decreasing pressure, causing air to flow in.

Question 6

Which of the following is NOT a correct comparison between arteries and veins?

Accepted Answer

Arteries have a larger lumen than veins.

Question 7

Which of the following best explains why capillaries cannot withstand high pressure?

Accepted Answer

They have thin walls and lack the thick muscular and elastic layers found in arteries.

Question 8

Which of the following best describes the role of the central nervous system (CNS)?

Accepted Answer

It integrates sensory information and coordinates responses.

Question 9

During an action potential, which event occurs immediately after the membrane potential reaches threshold?

Accepted Answer

Voltage-gated sodium channels open, causing rapid depolarization.

Question 10

A neuron receives both excitatory and inhibitory inputs. Which of the following best describes how it integrates these signals?

Accepted Answer

It fires an action potential if the sum of all inputs at the axon hillock reaches threshold.

Question 11

Which of the following is a correct sequence of events for synaptic transmission at a chemical synapse?

Accepted Answer

Action potential arrives at axon terminal → voltage-gated calcium channels open → neurotransmitter released → postsynaptic cell responds

Question 12

Which of the following best describes how sound waves are converted into action potentials in the mammalian inner ear?

Accepted Answer

Sound waves cause movement of fluid in the cochlea, bending hair cells and opening ion channels.

Question 13

Which of the following statements about rods and cones in the vertebrate eye is correct?

Accepted Answer

Cones are responsible for color vision and function best in bright light.

Question 14

Which of the following best describes the sliding filament mechanism of muscle contraction?

Accepted Answer

Myosin heads bind to actin and pull the thin filaments toward the center of the sarcomere.

Question 15

Which of the following is a correct comparison of the three types of animal skeletons?

Accepted Answer

Hydrostatic skeletons rely on fluid pressure, exoskeletons are external and rigid, and endoskeletons are internal and rigid.

Question 16

Which of the following best explains how peptide hormones signal target cells?

Accepted Answer

They bind to receptors on the cell surface, triggering a signal transduction pathway.

Question 17

Which of the following correctly describes the relationship among the hypothalamus, anterior pituitary, and posterior pituitary?

Accepted Answer

The hypothalamus produces hormones that are stored and released by the posterior pituitary, and it regulates hormone release from the anterior pituitary via releasing hormones.

Question 18

A person has low blood glucose levels. Which hormone is likely to be secreted to restore homeostasis, and what is its effect?

Accepted Answer

Glucagon; it stimulates the breakdown of glycogen to glucose in the liver.

Question 19

Which of the following best describes how the lymphatic system contributes to circulation?

Accepted Answer

It returns excess interstitial fluid to the bloodstream and helps filter pathogens.

BIO 114 Exam 3 Study Guide: Gas Exchange, Circulation, Nervous System, Sensory System, Animal Movement, and Chemical Signals

Study Guide - Practice Questions

Study Guide - Flashcards