Biology- Chapter 38

A chemical reaction has a Q10 of 2.5. At 30°C, the rate of the chemical reaction is 5. What is its rate at 40°C?

12.5

Refer to the graph. In this experiment, the same fish was caught and brought into the lab in both winter and summer. Its metabolic rates (O2 consumption) was measured at the pond temperatures for each season (?) and at other temperatures (′). The "winter fish" has a Q10 of _______; the "summer fish" has a Q10 of _______. 4; 4 4; 1 8; 2 (2; 2) 2; 1

2; 2

Your body is 60 percent water, two-thirds of which is intracellular fluid. If you weigh 150 pounds, about how much of your weight is due to water contained within your cells?

60 pounds

Which statement is correct? Collagen is a type of tissue. Some tissues are acellular. An organ performs a specific function and is composed of a single type of tissue. An organ is composed of an epithelium and one or more other kinds of tissues. Blood is not a tissue, because it is fluid.

An organ is composed of an epithelium and one or more other kinds of tissues.

Two tissues you would find inside your skull are shown in parts

B and E.

Which type of tissue has a high mineral content?

Bone

Which statement about the graph is true? Line A represents the rates of reactions of most biological processes in ectotherms. The Q10 for line C is 30 divided by 9.The Q10 for line B is higher than for line C. If line B represents the rate of a reaction in an organism in the summer, the line may shift when the reaction is measured in the winter. The rates of most biological reactions fall between lines A and B.

If line B represents the rate of a reaction in an organism in the summer, the line may shift when the reaction is measured in the winter.

Which characteristic pertains to brown fat?

Its cells have numerous mitochondria.

Which correctly represents an energy budget?

Metabolism + radiation absorbed = convection + conduction + evaporation + radiation lost

Which statement is true? Thermal tolerances are unrelated to the distribution ranges of organisms. The biochemical reactions of organisms are mostly independent of each other. Dramatic changes in body temperature are the result of homeostasis. Rapid environmental change, such as the present global warming, may place animals at risk of being exposed to conditions that exceed their thermal tolerances. Metabolic functions are more sensitive to long-term changes in temperature than to short-term changes.

Rapid environmental change, such as the present global warming, may place animals at risk of being exposed to conditions that exceed their thermal tolerances.

Which statement about endotherms is true? Some can acclimatize to seasonal temperature changes. They are unable to raise their body temperature through metabolic heat production. They can lower their body temperature by raising their basal metabolic rate. They respond to cold by lowering their metabolic rate. Their metabolic rate decreases above the thermoneutral zone.

Some can acclimatize to seasonal temperature changes.

Which statement about endotherms is true? -Endothermy likely evolved in animals where a mutation prevented leaks in ion channels, giving them a selective advantage by increasing their time of activity in the cooler night temperatures. -Some can use regulated hypothermia to conserve energy. -They respond to cold by mobilizing active mechanisms for heat loss. -They can raise their body temperature by mobilizing active mechanisms of heat loss. -They can lower their body temperature by producing heat metabolically.

Some can use regulated hypothermia to conserve energy.

Which statement is correct? Within the thermoneutral zone, an endotherm's thermoregulatory responses require a lot of energy. thermoneutral zone of an endotherm is bounded by a lower critical temperature and an upper critical temperature. Below the thermoneutral zone, an endotherm's thermoregulatory responses do not require a lot of energy. At temperatures well outside the thermoneutral zone, endotherms can still maintain their body temperatures without expending additional energy. Above the thermoneutral zone, an endotherm's thermoregulatory responses do not require a lot of energy.

The thermoneutral zone of an endotherm is bounded by a lower critical temperature and an upper critical temperature.

Macrophages engulf cellular debris, microbes, cancer cells, and foreign substances, so it is advantageous for them to be large. Why don't they keep growing ever larger?

Their size is limited by the amount of cell membrane surface area they have.

Which statement about glial cells is true? They provide immune functions for the central nervous system. They are insulated by neuronal processes. They secrete enzymes as part of an epithelium. They coordinate smooth muscle in the gut. They are found primarily in skeletal muscle tissue.

They provide immune functions for the central nervous system.

When people run, they sweat, which cools them as the sweat evaporates. Sweating is

an active process that generates heat in the process of dissipating heat.

Most physiological processes occur within a broad range of temperatures. have Q10 values greater than 3. go faster at lower temperatures. have Q10 values of 1. are temperature sensitive.

are temperature sensitive.

If you are ill and contract a fever, the portion of your _______ called the _______ has generated a new set point for your body's temperature.

brain; hypothalamus

Effectors cause change in the internal environment. stimulate negative feedback mechanisms. stimulate positive feedback mechanisms. control regulatory systems. provide feedback information for comparison with internal set points.

cause change in the internal environment.

Feedforward information is received by effectors. changes the set point. returns a physiological process to its normal set point. amplifies a response. eliminates feedback from the external environment.

changes the set point.

The mechanism of heat transfer that occurs when two physical objects at different temperatures come into direct contact is called

conduction

Homeostatic mechanisms in the human body

dampen fluctuations around a set point to keep internal conditions within a certain range.

A weight lifter does multiple sets of bench presses, as many repetitions per set as she can. If she cools her palms while resting between sets, she can increase the total number of lifts she can complete in her workout. The most likely explanation for this is that

extracting heat from the palms increases the capacity of arm muscles to do work.

Ectotherms can never increase body temperature above ambient temperature. have the same body temperatures as similar-size endotherms when the environmental temperature is near 0°C. have cells that are more leaky to ions than endotherms do. have lower metabolic rates than endotherms of the same body size. release more heat than do endotherms when maintaining concentration gradients of ions across membranes.

have lower metabolic rates than endotherms of the same body size.

Positive feedback returns a system to a set point. increases deviation from a set point. is more common than negative feedback in physiological systems. decreases the physiological response. is associated with responses that tend to terminate slowly.

increases deviation from a set point.

Stratified squamous epithelium is made up of a single layer of cube-shaped cells.is made up of tall, slender cells and is found in the gut. forms kidney tubules. is made up of several layers of cells, the outer layers of which are flattened. is made up of several layers of cube-shaped c

is made up of several layers of cells, the outer layers of which are flattened.

Acclimatization

is the physiological adjustment made by organisms to gradual changes in their environment.

When an ectotherm and an endotherm of the same body size are held in a closed chamber and the temperature is lowered, the

metabolic rate of the endotherm increases.

When compared with the thermal limits for life, the thermal tolerance of a given species is usually

narrower.

Shivering releases heat by converting ADP to ATP. relies on brown fat. occurs in birds and mammals. produces heat by increasing sweating. relies on contraction of smooth muscles.

occurs in birds and mammals.

In regulatory systems, sensors move the system away from the set point. issue commands to controlled systems. reflect internal conditions. integrate information. provide information to be compared with the internal set point.

provide information to be compared with the internal set point.

"Hot" fishes lose less heat to the water because they infrequently pass water over their gills. retain heat in swimming muscles. retain metabolic heat in their large dorsal aorta. swim slowly. can have a body temperature lower than the water temperature.

retain heat in swimming muscles.

Q10 describes the

temperature sensitivity of a reaction or process.