Ch. 42 Gas Exchange & Circulation

Predict how Antarctic icefish can transport enough oxygen in their blood to meet their needs even though they lack hemoglobin. a. Antarctic icefish has a high speed of blood circulation. b. Cold water carries more oxygen than warm water does. The oxygen is simply dissolved in the blood. c. Hemoglobin has more affinity to oxygen and carbon dioxide in low temperature. d. Antarctic icefish has a big quantity of erythrocytes.

b. Cold water carries more oxygen than warm water does. The oxygen is simply dissolved in the blood.

What do stomata do? a. transport water and ions b. facilitate gas exchange c. connect the cytoplasm of adjacent plant cells d. store wastes

b. facilitate gas exchange

What does the cuticle do? a. stores nutrients b. reduces water loss c. transports water and ions d. forms thorns

b. reduces water loss

Which of the following respiratory systems is NOT closely associated with the blood supply? a. the skin of an earthworm b. the tracheal system of an insect c. the lungs of a vertebrate d. the gills of a fish

b. the tracheal system of an insect

What is the correct order of processes involving the movement of oxygen from the environment to mitochondria in vertebrates? a. circulation, ventilation, cellular respiration b. ventilation, circulation, cellular respiration c. circulation, cellular respiration, diffusion in tissues d. diffusion in tissues, cellular respiration, diffusion at respiratory surface e. ventilation, diffusion in tissues, circulation

b. ventilation, circulation, cellular respiration

Atmospheric pressure at sea level is equal to a column of 760 mm Hg. Oxygen makes up 21 percent of the atmosphere by volume. The partial pressure of oxygen (PO2) in such conditions is _____. a. 120/75 b. 16 mm Hg c. 160 mm Hg d. 760/21 e. 21/760

c. 160 mm Hg

Which of the following aquariums would require the most air bubbled in to maintain oxygenation of the water: Aquarium A with warm water and some fish; Aquarium B with cold water, some fish, and some algae; or Aquarium C with warm salt water and some fish? See Section 42.1 (Page 875) . a. All the tanks would need the same amount of air bubbled in if they are the same volume. b. Aquarium B c. Aquarium C d. Aquarium A

c. Aquarium C-Warm temperature, lack of photosynthetic organisms, and salt all reduce water oxygenation.

Which feature is common to gills, lungs, and tracheae? See Section 42.3 (Page 878) . a. Countercurrent exchange mechanism b. Dead space c. Large surface area d. Delivering oxygen directly to cells without a circulatory system

c. Large surface area-Correct! All have a relatively large surface area for better gas exchange.

Countercurrent exchange in the fish gill helps to maximize ________. a. osmosis b. active transport c. extraction of oxygen from the water d. endocytosis e. blood pressure

c. extraction of oxygen from the water

At the summit of a high mountain, the atmospheric pressure is 380 mm Hg. If the atmosphere is still composed of 21percent oxygen, then the partial pressure of oxygen at this altitude is about _____. a. 380 mm Hg b. 760 mm Hg c. 0 mm Hg d. 160 mm Hg e. 80 mm Hg

e. 80 mm Hg

both oxygen and carbon dioxide

enters alveoli during inhalation transported by hemoglobin

Plants from wet habitats

have a relatively large number of stomata have thin cuticle

Plants from dry habitats

have relatively few stomata have thick cuticle

carbon dioxide only

net diffusion from body tissues to blood waste product of cellular respiration sometimes transported as bicarbonate net diffusion from lung capillaries to alveoli

oxygen only

required for cellular respiration net diffusion from alveoli to lung capillaries