BIO 206 final

Which of the following statements regarding the squid respiratory system is not accurate?

The branchial heart pumps highly-oxygenated blood to the gills.

How does the immune system of vertebrates utilize a chemical concentration gradient?

The immune system releases chemical signals called chemokines, which create a chemical gradient that leukocytes use in migrating toward the infection site.

Which of these is not a disadvantage of an open circulatory system compared with a closed circulatory system?

The molecules being exchanged between hemolymph and tissues do not have to diffuse across the wall of a circulatory vessel to reach a respiring cell.

If, during protein starvation, the osmotic pressure on the venous side of capillary beds drops below the hydrostatic pressure, then ________.

fluids will tend to accumulate in the interstitial fluid and tissues.

Compare osmoregulation in a marine bony fish, such as tuna, with a freshwater bony fish, such as catfish. The catfish

has chloride channels in the gills that take up chloride ions from their environment, whereas tuna have chloride channels in the gills that secrete chloride ions into the environment.

Carbon dioxide levels in the blood and in cerebrospinal fluid affect pH of these fluids. This enables the organism to sense a disturbance in gas levels as ________.

neurons in contact with cerebrospinal fluid monitor pH and use this measure to control breathing

The velocity of blood flow is the lowest in capillaries because

. the total cross-sectional area of the capillaries is greater than the total cross- sectional area of the arteries or any other part of the circulatory system.

. An animal has a cardiac output of 40 mL/min (milliliters per minute) and a stroke volume of 5.0 mL. What is its heart rate?

8 beats/minute

A stroke volume of 70 mL/beat in a heart with a pulse of 72 beats per minute results in a cardiac output of about ________.

5 liters per minute

Which of these is not an advantage of breathing air instead of water for gas exchange?

Air is relatively dry compared to animal tissues

. Mast cells release lysozyme to prevent bacteria from invading the mucus barrier on human skin.

False

The sinoatrial node and atrioventricular node fire action potentials simultaneously to enable the atria to contract at the same time as the two ventricles.

False

Capillaries exhibit extremely thin walls, as little as a single cell in thickness, which is a characteristic that is important to their overall function. How can such highly functional yet structurally thin capillary walls be maintained without rupturing?

In regions where capillaries are found, they form beds of highly branched vessels.

When athletes exercise, what is the primary physiological variable responsible for their sustained increase in ventilation rate?

Increased partial pressure of CO2 in the blood

Consider how natural selection has worked on the parameters included in Fick's Law to maximize respiration efficiency in animals. In this regard, which of these statements about the characteristics of the mammalian lung is not true?

Lungs increase the temperature of the air and are moist, allowing greater solubility of gases at the respiratory surface, increasing the diffusion coefficient k.

The panels below depict the change in oxygen saturation in the capillaries underlying gill lamellae and the oxygen content of the water that flows across that gill lamellae. Which of the panels depict(s) countercurrent exchange of oxygen?

Panel A only.

In animal respiratory systems, ventilation with water requires more metabolic energy than ventilating with air.

True

A species that has a normal resting systolic blood pressure of greater than 260 mm Hg is likely to be ________.

an animal that has a very long distance between its heart and its brain

Compare the proximal convoluted tubule (PCT) with the thick segment of the ascending limb in the loop of Henle (thick limb). The proximal convoluted tube (PCT)

contains filtrate with an osmolarity of 300milliosmoles/L over the entire length of the PCT, whereas the osmolarity of the fluid in the thick limb changes over the length of the thick limb.

The atrioventricular (AV) node serves to ________.

delay the heartbeat signal before transmitting it to the ventricles

Birds that live in marine environments, and thus lack access to fresh drinking water, ________.

drink seawater and secrete excess ions mainly through their nasal salt glands

The sodium/potassium pump

enables passive entry of sodium ions and passive exit of potassium ions through secondary active transport.

. Memory in B cells

increases the speed and strength of the immune response.

One feature that amphibians and humans have in common is ________.

separate pulmonary and systemic circuits

What is present in arterioles that is NOT present in capillaries?

smooth muscle cells

Which of the following best describes the process of ventilation?

the movement of the respiratory medium over the respiratory surface

If a molecule of carbon dioxide enters the blood in your left toe and is exhaled from your nose, it must pass through all of the following EXCEPT ________.

the pulmonary vein

At the top of Mount Baker, the partial pressure of oxygen is lower than it is in downtown Bellingham, but the percentage of O2 is the same in both places.

true