Question 1

According to Fick’s Law of Diffusion, which of the following adaptations would most effectively increase the rate of gas exchange in an aquatic animal’s gills?

Accepted Answer

Increasing the partial pressure difference of oxygen across the gill membrane

Question 2

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 3

Countercurrent flow in fish gills is more efficient than concurrent flow because:

Accepted Answer

It maintains a constant partial pressure gradient along the entire length of the gill

Question 4

Which of the following best explains why mammalian lungs are not 100% efficient at gas exchange, even though they have a large surface area?

Accepted Answer

The partial pressure gradient of oxygen is not maximized due to residual air in the lungs

Question 5

During vigorous exercise, the Bohr shift causes hemoglobin to release more oxygen to tissues. Which change in the blood triggers this effect?

Accepted Answer

A decrease in blood pH

Question 6

Which of the following best describes how carbon dioxide is primarily transported in the blood?

Accepted Answer

As bicarbonate ions ($$\mathrm{HCO}_3^-) in $$plasma

Question 7

Which of the following is a correct sequence of events during the cardiac cycle?

Accepted Answer

Atrial contraction → ventricular contraction → atrioventricular valves close → semilunar valves open

Question 8

Which structural feature allows arteries to withstand the high pressure generated by the heart?

Accepted Answer

A thick layer of elastic connective tissue and smooth muscle

Question 9

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

Accepted Answer

They lack smooth muscle and have only a single layer of endothelial cells

Question 10

A patient is diagnosed with a disorder that impairs the function of their lymphatic system. Which of the following symptoms would most likely result?

Accepted Answer

Edema (swelling) due to accumulation of interstitial fluid

Question 11

Which of the following best describes the role of voltage-gated sodium channels in the generation of an action potential?

Accepted Answer

They open when the membrane potential reaches threshold, allowing Na$$^+$$ influx and depolarization

Question 12

Which of the following is a function of the sympathetic division of the autonomic nervous system?

Accepted Answer

Increasing heart rate and dilating bronchioles during a 'fight or flight' response

Question 13

Which of the following best explains how sensory information is transmitted from a mechanoreceptor to the central nervous system?

Accepted Answer

Mechanical pressure opens gated ion channels, generating a receptor potential that triggers action potentials

Question 14

Which of the following statements correctly distinguishes between rods and cones in the vertebrate eye?

Accepted Answer

Rods detect dim light and are more sensitive, while cones are responsible for color vision

Question 15

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

Accepted Answer

Actin filaments slide past myosin filaments, shortening the sarcomere

Question 16

Which of the following is a key difference between peptide hormones and steroid hormones?

Accepted Answer

Peptide hormones are hydrophilic and bind to cell surface receptors, while steroid hormones are lipophilic and bind intracellular receptors

Question 17

A patient has high blood glucose levels after a meal. Which hormone is released to restore homeostasis, and what is its effect?

Accepted Answer

Insulin; stimulates uptake of glucose by cells and storage as glycogen

Question 18

Which of the following best describes how peptide hormones transmit their signal into a target cell?

Accepted Answer

They bind to cell surface receptors, triggering a signal transduction cascade inside the cell

Question 19

Which of the following best describes the relationship between the hypothalamus and the pituitary gland?

Accepted Answer

The hypothalamus produces hormones that are stored and released by the posterior pituitary

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

Study Guide - Practice Questions

Study Guide - Flashcards