Prelim 2 Questions Flashcards
Which of the following statements correctly describes phototrophs and chemotrophs?
A. All phototrophs are unicellular
B. Chemotrophs obtain energy from chemicals and phototrophs obtain energy from light
C. Both obtain their energy from light
Both obtain their energy from chemicals
D. Both obtain their energy from chemicals
B. Chemotrophs obtain energy from chemicals and phototrophs obtain energy from light
Which statement best explains how the digestion and absorption of fats differs from that of carbohydrates?
A. Carbohydrates require emulsification before digestion whereas fats do not.
B. Most absorbed fat first enters the lymphatic system, whereas digested carbohydrates directly enter the blood.
C. Fats, but not carbohydrates, are digested by bacteria before absorption.
D. Fat absorption primarily occurs in the stomach, whereas carbohydrates are absorbed from the small intestine.
E. Fats must be completely digested before being absorbed while carbohydrates can be absorbed before they are completely broken down.
B. Most absorbed fat first enters the lymphatic system, whereas digested carbohydrates directly enter the blood.
Consider an ectotherm and an endotherm of equal body size. The ectotherm is more likely to survive food deprivation for a longer period of time than the endotherm because:
A. the ectotherm has greater insulation on its body surface.
B. the ectotherm is sustained by a higher basal metabolic rate.
C. ectotherms always expend less energy on growth than comparably sized endotherms.
D. the ectotherm will expend more energy per kilogram of body weight than the endotherm.
E. the ectotherm will invest little or no energy in temperature regulation.
E. the ectotherm will invest little or no energy in temperature regulation.
All of the following processes can cause an animal to acquire heat EXCEPT:
A. uncoupling of cellular respiration from ATP
B. synthesis.
C. evaporation.
D. convection.
E. metabolism.
F. radiation.
C. evaporation.
The nutrient procurement function of the root hairs of a plant is most analogous to the function of which of the following?
A. microvilli and villi of the cells lining the small intestine of a mammal
B. the gastrovascular cavity of a hydra
C. the food vacuoles of a sponge
D. amoeba feeding by phagocytosis and cytoplasmic streaming
A. microvilli and villi of the cells lining the small intestine of a mammal
How does countercurrent exchange increase regional heterothermy in arctic foxes?
A. Heat from the veins helps warm up the blood in arteries due to conduction.
B. Heat from the veins helps warm up the blood in arteries due to radiation.
C. Blood vessels close to one another increase heat transfer between vessels and increase conductive heat loss from the skin.
D. Blood vessels close to one another reduce heat transfer between vessels and increase radiative heat loss from skin.
E. Blood vessels close to one another increase heat transfer between vessels and reduce heat loss from appendages.
E. Blood vessels close to one another increase heat transfer between vessels and reduce heat loss from appendages.
One circulatory feature that amphibians and humans have in common is:
A. A heart that pumps only oxygenated blood.
B. a low arterial blood pressure in the systemic circuit.
C. they both contain a pulmonary and systemic circuit.
D. a complete separation of circuits for circulation.
E. a single ventricle.
C. they both contain a pulmonary and systemic circuit.
If the osmotic pressure on the venous side of capillary beds drops below the hydrostatic (blood) pressure, then:
A. precapillary sphincters will relax.
B. precapillary sphincters will contract.
C. fluids will tend to accumulate in tissues
D. plasma proteins will escape through the endothelium of the capillaries.
C. fluids will tend to accumulate in tissues
Which statement about the heart and circulation in humans is correct?
A. The flow of blood through the networks of systemic capillaries is relatively constant.
B. Blood pressure is higher during diastole than it is during systole.
C. Contraction of the mammalian heart is initiated by the atrioventricular (AV) node.
D. Movement of fluid in the circulatory system removes the necessity for diffusion in animals possessing circulatory systems.
E. Blood pressure is typically highest in the arteries, intermediate in the capillaries, and lowest in the veins.
E. Blood pressure is typically highest in the arteries, intermediate in the capillaries, and lowest in the veins.
Sieve tube elements of phloem tissue can build up a turgor pressure 5-10 times that in an automobile tire. How are sieve elements able to establish such high pressures?
A. Nutrients diffuse passively into the sieve elements in leaf veins in response to a concentration gradient.
B. Nutrients are actively transported into sieve elements, and water follows passively by osmosis.
C. Nutrients are actively transported into sink regions of sieve elements, and water follows passively to lower the turgor pressure.
D. Negative pressure in the xylem causes positive pressure build-up in the adjacent phloem cells.
E. Water is actively transported into the sieve elements to build up a high turgor pressure.
B. Nutrients are actively transported into sieve elements, and water follows passively by osmosis.
If damage occurs to the pulmonary semilunar valve in the heart such that the valve fails to close properly:
A. blood would accumulate in the left ventricle.
B. blood would be forced backwards from the right ventricle into the right atrium during systole.
C. the left side of the heart would enlarge.
D. there would be backflow of blood into the right ventricle.
E. the blood pressure in the aorta would be decreased.
D. there would be backflow of blood into the right ventricle.
In order for blood to be brought back properly from the lower extremities of the human body to the heart, it is necessary that:
A. skeletal muscle contraction occurs.
B. both skeletal muscle contraction occurs and one-way valves in veins prevent backflow.
C. arterial blood pressure remains as high in the veins as in the arteries.
D. the veins have one-way valves.
B. both skeletal muscle contraction occurs and one-way valves in veins prevent backflow.
Damage to the sinoatrial (SA) node in humans is most likely to result in a:
A. disruption on the rate and timing of cardiac muscle contractions.
B. direct effect on blood pressure sensors in the aorta.
C. negative effect on peripheral resistance.
D. blockage in conductance between the bundle branches and the Purkinje fibers.
A. disruption on the rate and timing of cardiac muscle contractions.
The body fluids of an osmoconformer would be _______ with its _______ environment.
A. hyperosmotic; seawater
B. isosmotic; seawater
C. hypoosmotic; seawater
D. hyperosmotic; freshwater
B. isosmotic; seawater
Upon dehydration, the brain modifies your behavior and can generate thirst as well as induce a craving for salt. Which statement is true?
A. Intracellular thirst occurs when blood volume drops. It triggers the activation of baroreceptor cells that stimulate thirst.
B. Extracellular thirst occurs when blood volume drops. It triggers the activation of baroreceptor cells that stimulate thirst and craving for salt.
C. Intracellular thirst occurs when blood osmolarity increases. It causes a shape change of osmoreceptor cells that stimulates thirst and craving for salt.
D. Extracellular thirst occurs when blood osmolarity increases. It triggers a shape change of osmoreceptor cells that stimulates thirst and craving for salt.
B. Extracellular thirst occurs when blood volume drops. It triggers the activation of baroreceptor cells that stimulate thirst and craving for salt.
