Biology II Unit 2

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 _____.

160 mm Hg.

A patient with a blood pressure of 120/75, a pulse rate of 70 beats/minute, a stroke volume of 70 mL/beat (milliliters per beat), and a respiratory rate of 25 breaths/minute will have a cardiac output of _____.

4,900 mL/minute.

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 _____.

80 mm Hg. (380*0.21)

Organisms with a circulating body fluid that is distinct from the fluid that directly surrounds the body's cells are likely to have _____.

a closed circulatory system.

Which of the following is the best definition of autoimmune disease?

a condition in which self-molecules are treated as non-self.

Ingested dietary substances must cross cell membranes to be used by the body. This process is known as _____.

absorption.

A normal event in the process of blood clotting is the _____.

activation of prothrombin to thrombin.

Clonal selection is an explanation for how _____.

an antigen can provoke production of high levels of specific antibodies.

An anthropologist discovers the fossilized heart of an extinct animal. The evidence indicates that the organism's heart was large, was well-formed, and had four chambers, with no connection between the right and left sides. A reasonable conclusion supported by these observations is that the _____.

animal was endothermic and had a high metabolic rate.

A patient complaining of watery, itchy eyes and sneezing after being given a flower bouquet as a birthday gift should first be treated with _____.

antihistamines.

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

carbon dioxide.

Septic shock, a systemic response including high fever and low blood pressure, is a response to _____.

certain bacterial infections.

Most types of communication between cells utilize _____.

chemical or electrical signals.

Most of the carbon dioxide produced by humans is _____.

converted to bicarbonate ions by an enzyme in red blood cells.

T cells of the immune system include _____.

cytotoxic and helper cells.

Countercurrent exchange in the fish gill helps to maximize _____.

diffusion.

Atria contract _____.

during systole.

If you gently bend your ear, and then let go, the shape of your ear will return because the cartilage of your ear contains_____.

elastic fibers.

The hormone that stimulates the production of red blood cells, and the organ where this hormone is synthesized, are _____.

erythropoietin and kidney, respectively.

Sweating allows a person to lose heat through the process of _____.

evaporation.

Animals that migrate great distances would obtain the greatest energetic benefit of storing chemical energy as _____.

fats.

When a woman has her gallbladder removed, she should probably reduce her consumption of _____.

fats.

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 tissues.

Among the following choices, which organism likely has the highest systolic pressure?

giraffe.

Cattle are able to survive on a diet consisting almost entirely of plant material because cattle _____.

have cellulose-digesting, symbiotic microorganisms in chambers of their stomachs.

The function of mechanical digestion is to break down large chunks of food into smaller pieces. Why is this important? Smaller pieces of food _____.

have more surface area for chemical digestion than do larger pieces of food.

A relatively long cecum is characteristic of animals that are_____.

herbivores.

The body's automatic tendency to maintain a constant and optimal internal environment is termed _____.

homeostasis.

The temperature-regulating center of vertebrate animals is located in the _____.

hypothalamus.

Villi and microvilli in the small intestine _____.

increase the surface area to increase the efficiency of nutrient absorption.

Inflammatory responses typically include _____.

increased activity of phagocytes in an inflamed area.

Small swollen areas in the neck, groin, and axillary region are associated with _____.

increased activity of the immune system.

An individual who has been bitten by a poisonous snake that has a fast-acting toxin would likely benefit from _____.

injection of antibodies to the toxin.

In a healthy person, after a large meal, the production of _____ will increase. After fasting, the production of _____ will increase.

insulin; glucagon.

In a cool environment, an ectotherm is more likely to survive an extended period of food deprivation than would an equally sized endotherm because the ectotherm _____.

invests little energy in temperature regulation.

Innate immunity _____.

is activated immediately upon infection.

Blood is best classified as connective tissue because _____.

its cells are separated from each other by an extracellular matrix.

Some human infants, especially those born prematurely, suffer serious respiratory failure because of _____.

lung collapse due to inadequate production of surfactant.

Vaccination increases the number of _____.

lymphocytes with receptors that can bind to the pathogen.

If a patient is missing B and T cells, what would be absent from the immune response?

memory.

As the size of some animals has evolved to greater sizes, the effectiveness of their adaptations that promote exchanges with the environment have also increased. For example, in many larger organisms, evolution has favored lungs and a digestive tract with _____.

more branching or folds.

The absorption of fats differs from that of carbohydrates in that _____.

most absorbed fat first enters the lymphatic system, whereas carbohydrates directly enter the blood.

When the body's blood glucose level rises, the pancreas secretes insulin and, as a result, the blood glucose level declines. When the blood glucose level is low, the pancreas secretes glucagon and, as a result, the blood glucose level rises. Such regulation of the blood glucose level is the result of _____.

negative feedback.

An immunoglobulin (Ig) molecule, of whatever class, with regions symbolized as C or V, H or L, has a light chain made up of _____.

one C region and one V region.

The Bohr shift on the oxygen-hemoglobin dissociation curve is produced by changes in _____.

pH.

What type of immunity is associated with breast feeding?

passive immunity.

Mucus occurs in both the respiratory and digestive tracts. What is its main immunological function?

physically trapping pathogens.

Naturally acquired passive immunity can result from the _____.

placental transfer of antibodies.

Once labor begins in childbirth, contractions increase in intensity and frequency, causing more contractions to occur until delivery. The increasing labor contractions of childbirth are an example of which type of regulation?

positive feedback.

Which of the following is crucial to activation of the adaptive immune response?

presentation of MHC (major histocompatibility complex)-antigen complex on a cell surface.

A woman standing and watching the stars on a cool, calm night will lose most of her body heat by _____.

radiation.

Yearly vaccination of humans for influenza viruses is necessary because _____.

rapid mutation in flu viruses alters the surface proteins in infected host cells.

Clonal selection and differentiation of B cells activated by antigen exposure leads to the production of _____.

short-lived plasma cells that secrete antibodies for the antigen.

In the digestive system, peristalsis is _____.

smooth muscle contractions that move food along the esophagus.

Digestive secretions with a pH of 2 are characteristic of the _____.

stomach.

Penguins, seals, and tuna have body forms that permit rapid swimming, because _____.

the shape is a convergent evolutionary solution, which reduces drag while swimming.

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.

Jenner's successful use of cowpox virus as a vaccine against the smallpox virus was due to the fact that _____.

there are some epitopes (antigenic determinants) common to both pox viruses.

Certain nutrients are considered "essential" in the diets of some animals because _____.

these animals are not able to synthesize these nutrients.

Hummingbirds are small birds that require a regular food supply. When hummingbirds are faced with a situation that decreases their food supply, such as a storm, which of the following adaptations would be most useful for the bird to survive such an unpredictable and short-term absence of food resources?

torpor.

Obesity in humans is most clearly linked to _____.

type 2 diabetes and cardiovascular disease.

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

vena cava → right atrium → right ventricle → pulmonary artery.

Damage to the sinoatrial node in humans _____.

would disrupt the rate and timing of cardiac muscle contractions.