Mastering Biology Final

Freshwater fish excrete nitrogenous wastes as ____

AMMONIA

Which of the following causes Earth's seasons?

Earth's tilt on its axis

Like other osmoregulatory animals that live in marine environments, sharks maintain tissue concentrations of sodium, potassium, and chloride that are hypoosmotic to the seawater. In contrast to the bony marine fishes, however, sharks do not need to drink seawater. Why?

High urea and trimethylamine oxide concentrations keep shark tissues slightly hyperosmotic relative to seawater, so water is absorbed passively.

Which statement about lipoproteins is correct?

High-density lipoproteins are cholesterol transporters in the blood.

Which of the following contribute to maintaining the high osmolarity of the renal medulla? I) active transport of salt from the upper region of the ascending limb II) the spatial arrangement of juxtamedullary nephrons III) diffusion of urea from the collecting duct IV) diffusion of salt from the descending limb of the loop of Henle

I, II, and III

Blood cells that function to fight infection are called ____

LEUKOCYCTES

Which of the following represents the correct sequence of flow through the nephron?

Renal corpuscle > proximal tubule > loop of Henle > distal tubule > collecting duct

A normal event in the process of blood clotting is the ___

activation of prothrombin to thrombin

___ in carbon dioxide in your red blood cells, which causes _____ in pH, causes your breathing to speed up.

an increase; a drop

The diagnosis of hypertension in adults is based on the ___

blood pressure being greater than 140 mm Hg systolic and/or greater than 90 mm Hg diastolic

In order for blood to always flow unidirectionally through a closed circulatory system, the _____

blood vessels farthest from the heart must have valves.

During most daily activities, the human respiration rate is most closely linked to the blood levels of ____

carbon dioxide

Most of the carbon dioxide produced by humans is ___

converted to bicarbonate ions

Large proteins such as albumin remain in capillaries rather than diffusing out, resulting in the ____

development of an osmotic pressure difference across capillary walls

Countercurrent exchange in the fish gill helps to maximize ___

diffusion

Damage to the sinoatrial node in humans would _____

disrupt the rate and timing of cardiac muscle contractions

_____ is a hormone that is released from the ________ to stimulate the production of red blood cells.

erythropoietin; kidney

To maintain homeostasis, freshwater fish must _____

excrete large quantities of water

Nitrogen is absent from

fatty acids

Which process in the nephron is least selective?

filtration

Low selectivity of solute movement is a characteristic of ___

filtration from the glomerular capillaries

The only vertebrates in which blood flows directly from respiratory organs to body tissues without first returning to the heart are the ___

fishes

To adjust blood pressure independently in the capillaries of the gas-exchange surface and in the capillaries of the general body circulation, an organism would need a(n) ___

four chambered heart

In which of the following organisms does blood flow from the pulmocutaneous circulation to the heart before circulating through the rest of the body?

frogs

How has the avian lung adapted to the metabolic demands of flight?

gas exchange occurs during both inhalation and exhalation

A decrease of blood pH from 7.4 to 7.2 causes hemoglobin to _____

give up more of its oxygen molecules

In which of the following animals are the blood and the interstitial fluid considered to be the same body fluid?

grasshoppers

Under identical atmospheric conditions, freshwater _____

has more dissolved oxygen than seawater

If ATP production in a human kidney was suddenly halted, urine production would ____

increase and the urine would be isoosmotic compared to plasma

The amount of oxygen bound to hemoglobin ___

increases in the presence of high concentrations of oxygen

Compared to the seawater around them, most marine invertebrates are _____

isoosmotic

The body fluids of an osmoconformer would be ________ with its ________ environment

isoosmotic; seawater

Developing bird embryos excrete most of their nitrogenous waste as uric acid because ______

it has a low solubility in water and is less toxic to the embryo than other forms of waste

An examination of a marine sea star that had died after it was mistakenly placed in fresh water would likely show that it died because ______

it was so hypertonic to the fresh water that it could not osmoregulate

Among the following choices, the most concentrated urine is excreted by ___

kangaroo rats

Which of the following represents the correct flow of air into the lung of a mammal?

larnyx → trachea → bronchi → bronchioles → alveoli

An examination of a freshwater fish that died after being placed accidentally in saltwater would likely show that _____

loss of water by osmosis from cells in vital organs resulted in cell death and organ failure

Which statement accurately describes the potential effects of disturbance on species diversity?

many species are well adapted to survive periodic disturbances.

Atrial systole ____

occurs at the same time as ventricular diastole

As a property of enzymes, cooperativity refers to

one enzyme subunit altering the behavior of others.

Which of the following events would you predict as carbon dioxide is released from your muscles into the surrounding capillary bed?

oxygen delivery to muscle is increased when more carbon dioxide is produced by the muscle

A human who has no access to fresh water but is forced to drink seawater instead will ______

passively excrete excess water in order to remove the high concentration of ingested salt

Cellular respiration

produces CO2 and ATP.

Which statement about human blood vessels is correct? Arteries carry blood toward the atria of the heart. The pulmonary artery carries oxygen-rich blood from the lungs. Arteries carry oxygenated blood; veins carry oxygen-poor blood. Veins transport blood from the heart to the capillaries. Pulmonary veins carry oxygen-rich blood to the heart.

pulmonary veins carry oxygen-rich blood to the heart

Hyperventilation (rapid inhalation and exhalation) can result in respiratory alkalosis (increased blood pH). Why?

rapid breathing depletes the blood of carbon dioxide, thus the blood pH increases.

Unlike an earthworm's metanephridia, a mammalian nephron

receives filtrate from blood instead of coelomic fluid.

When you hold your breath, which of the following blood gas changes first leads to the urge to breathe?

rising CO2

The fluid with the highest osmolarity is ____

seawater in a tidal pool

African lungfish, which are often found in small stagnant pools of fresh water, produce urea as a nitrogenous waste. What is the advantage of this adaptation?

small stagnant pools do not provide enough water to dilute the toxic ammonia.

Which of the following develops the greatest pressure on the blood in the mammalian aorta?

systole of the left ventricle

Which of the following statements comparing respiration in fish and in mammals is correct?

the movement of the respiratory medium in mammals is bidirectional, but in fish it is unidirectional.

If a molecule of CO2 released into the blood in your left toe is exhaled from your nose, it must pass through all of the following except

the pulmonary vein

The greatest difference in the concentration of respiratory gases is found in which of the following pairs of mammalian blood vessels?

the pulmonary vein and the superior vena cava

Circulatory systems compensate for ___

the slow rate at which diffusion occurs over large distances

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

Which of the following respiratory systems is not closely associated with a blood supply?

the tracheal system of an insect

Within a normally functioning kidney, blood can be found in ___

the vasa recta

What role do transport epithelia play in osmoregulation of marine fish with bony skeletons?

they are involved in excretion of excess salt.

Unlike most bony fishes, sharks maintain body fluids that are isoosmotic to seawater, so they are considered by many to be osmoconformers. Nonetheless, these sharks osmoregulate at least partially by ____

tolerating high urea concentrations that are balanced with internal salt concentrations to seawater osmolarity

What is the difference between a countercurrent multiplier system, such as the one involving the loop of Henle, and the countercurrent systems that maximize oxygen absorption by fish gills or reduce heat loss in endotherms?

unlike the other countercurrent systems, a countercurrent multiplier system, such as the one involving the loop of Henle, expends energy in active transport.

The advantage of excreting nitrogenous wastes as urea rather than as ammonia is that _____

urea is less toxic than ammonia

Which of the following is characteristic of most terrestrial biomes?

vegetation demonstrating vertical layering

Which of the following is the correct sequence of blood flow in birds and mammals?

vena cava → right atrium → right ventricle → pulmonary artery

An advantage of gas exchange in fresh water, compared with gas exchange in air, is that ___

water loss through evaporation across the respiratory surface can be minimized