Mastering BIO Exam 3

Thermoregulation in the body is accomplished by several feedback systems. The feedback system shown uses vasoconstriction and vasodilation in the skin and extremities to regulate body temperature.

A. vasodilation B. body temperature decreases C. homeostasis D. body temperature increases E. vasoconstriction This is a negative feedback loop

What is the driving force for the filtration of blood by the renal corpuscle?

Higher pressure in glomerular capillaries than in the surrounding Bowman's capsule.

Which regions of the nephron function independently of hormonal control for the most part?

Renal corpuscle, proximal tubule, and loop of Henle.

Homeostasis typically relies on negative feedback because positive feedback __________.

drives processes to completion rather than to a balance point

The loss of water from the _______results in urine that is highly concentrated

filtrate

Trees are rare in the savanna biome because of

frequent fires.

What are the most abundant animals found in the pelagic zone?

zooplankton

Which of the following actions is not a function of the epithelium?

Allows the internal environment to alter its conditions to match those of the external environment.

Which term describes a steady state in which the internal conditions of an organism are kept within a narrow range without regard to the external conditions?

Regulatory homeostasis.

The most abundant solute in urine is _____.

urea (and other nitrogenous wastes)

Active transport

-against a concentration gradient -requires energy from cells -sodium-potassium pump

Passive transport

-down a concentration gradient -does not require energy from cells -osmosis

collecting duct

1. active transport of NaCl associated with loss of water from filtrate 2. hormones control permeability to water and transport of NaCl

descending limb of loop of henle

1. numerous aquaporins (water channels) but almost no ion channels 2. no energy required for transport 3. epithelium always permeable to water

ascending limb of loop of henle

1. passive transport of NaCl in the thin segment and active transport of NaCl in the thick segment 2. no aquaporins (water channels)

Which of the following statements best describes the actions of the hormone ADH on the nephron?

ADH causes the collecting duct to increase water reabsorption by the surrounding tissue under conditions of dehydration.

Increases water reabsorption

ADH secretion, dehydration due to inadequate water intake, sweating, eating salty food

Which of the following statements describes a negative feedback response?

After a meal, blood sugar levels in the body rise; insulin is secreted to lower blood sugar levels.

Which of these is an example of negative feedback?

After you eat, insulin stimulates the lowering of blood sugar levels.

____ are the main male hormones

Androgens

Which statement describes how climate might change if Earth was 75% land and 25% water?

Earth's daytime temperatures would be higher and nighttime temperatures lower.

Which of the following causes Earth's seasons?

Earth's tilt on its axis

Which of the following is an accurate statement about thermoregulation?

Endotherms and ectotherms differ in their primary source of heat for thermoregulation.

What would be the effect on climate in the temperate latitudes if Earth were to slow its rate of rotation from a 24-hour period of rotation to a 48-hour period of rotation?

Larger ranges between daytime high and nighttime low temperatures would be frequent.

In which region of the nephron is a steep osmotic gradient created?

Loop of Henle

Which of the following statements best describes the interaction between fire and ecosystems?

Many kinds of plants and plant communities have adapted to frequent fires.

This osmolarity gradient is maintained by both the passive transport and the active transport of

NaCl

Which of the following statements best describes the effect of climate on biome distribution?

Not only is the average climate important in determining biome distribution, but so is the pattern of climatic variation

Why is the climate drier on the leeward side of mountain ranges that are subjected to prevailing winds?

Pushed by the prevailing winds on the windward side, air is forced to rise, cool, condense, and drop its precipitation, leaving drier air to descend the leeward side.

Palm trees and subtropical plants are commonplace in Land's End, England, whose latitude is the equivalent of Labrador in coastal Canada, where the local flora is subarctic. Which statement best explains why this apparent anomaly exists between North America and Europe?

Regions such as Labrador are actually colder than England because colder Arctic water flows down to eastern North America and warm water from the equator flows to England.

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

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

Which of the following events might you predict to occur if the tilt of Earth's axis relative to its plane of orbit was increased to 33 1/2 degrees?

Summers and winters in the United States would likely become warmer and colder, respectively.

What might be the adaptive significance of these unusual forests growing the way they do in this marginal habitat?

Taproot formation is impossible, so trees developed shallow root beds and easily tilt.

What is the basic functional unit of the kidney?

The nephron. Nephrons perform the work required to maintain water and electrolyte balance.

Why are experiments that involve transplanting species seldom conducted today?

The transplanted species are often disruptive to their new communities.

Air masses formed over the Pacific Ocean are moved by prevailing westerlies where they encounter extensive north-south mountain ranges, such as the Sierra Nevadas and the Cascades. Which statement best describes the outcome of this encounter between a landform and an air mass? Air masses formed over the Pacific Ocean are moved by prevailing westerlies where they encounter extensive north-south mountain ranges, such as the Sierra Nevadas and the Cascades. Which statement best describes the outcome of this encounter between a landform and an air mass?

The warm, moist Pacific air rises and cools, releasing precipitation as it moves up the windward side of the range, and this cool, now dry air mass heats up as it descends on the leeward side of the range.

What is a biome?

a major type of ecosystem

Which marine zone is expected to have the lowest rates of primary productivity (photosynthesis)?

abyssal

Glucose is removed from filtrate by

active transport

What hormone promotes water retention by the kidneys?

antidiuretic hormone (ADH)

Animals can be classified according to their mode of thermoregulation. Sort the animals below, indicating their likely thermoregulatory strategy. homeothermic ectotherm

arctic shrimp

Receptors for nonsteroid hormones are located in _____.

association with a cell's plasma membrane Submit

Which is the most inclusive level of organization in nature?

biosphere

Which of these is NOT one of the four major categories of tissue?

blood

increases both water and Na+ reabsorbtion

blood loss, aldosterone release, severe diarrhea

cardiac muscle is the only muscle composed of ____ fibers

branched

Which hormone opposes the action of parathyroid hormone?

calcitonin

Many kinds of plants and plant communities have adapted to frequent fires.

can change the species composition within biological communities.

In which of the following terrestrial biome pairs are both biomes dependent upon periodic burning?

chaparral and savanna

The body tissue that consists largely of material located outside of cells is __________.

connective tissue

If a meteor impact or volcanic eruption injected a lot of dust into the atmosphere and reduced the sunlight reaching Earth's surface by 70% for one year, which of the following marine communities most likely would be least affected?

deep-sea vent

a neuron consists of

dendrites, a cell body, and axons

Deserts typically occur in a band around 30 degrees north and 30 degrees south latitude because

descending air masses originating from the tropics tend to be dry.

In which biome would you most likely find plants that exhibit C4 or CAM photosynthesis?

desert

Does not increase water or Na+ reabsorption

diabetes insipidus, alcohol consumption, caffeine consumption

Which of the following choices causes all of the others in creating global terrestrial climates?

differential heating of Earth's surface

parts of the nephron

distal tubule proximal tubule Bowman's capsule renal cortex renal medulla collecting duct loop of Henle glomerulus

Which of the following levels of ecological organization is arranged in the correct sequence from most to least inclusive?

ecosystem, community, population, individual

Which of these hormones are responsible for the "fight or flight" response to danger?

epinephrine and norepinephrine

Which of these is a nonsteroid hormone?

epinephrine and oxytocin

Which of these extracellular signal molecules could diffuse through a plasma membrane and bind to an intracellular receptor?

estrogen

A(n) _____ is a region where fresh water and salt water mix.

estuary

The movement of substances out of the glomerulus and into Bowman's capsule is referred to as _____.

filtration

Adrenocorticotropic hormone (ACTH) triggers the release of _____ in response to stress.

glucocorticoids

Which of these glands secretes releasing hormones?

hypothalamus

Which component of a homeostatic system compares sensory information to a target value?

integrator

Which of the following investigations is an example of the study of an abiotic factor?

investigating how the amount of annual precipitation affects the distribution of a tree species

Which hormone stimulates hormone production by the ovaries and testes?

luteinizing hormone (LH)

The _____ biome is the largest of Earth's biomes.

marine

The kidney's ability to concentrate urine depends on the maintenance of an osmolarity gradient between the interstitial fluid of two structures: the cortex and the

medulla

As filtrate moves down the loop of Henle, the surrounding interstitial fluid becomes _____ concentrated than the filtrate, so _____ leaves the filtrate.

more / water

How do nonsteroid hormones differ from steroid hormones?

nonsteroid hormones act via signal transduction pathways; steroid hormones do not act via signal transduction pathways

The growing season would generally be shortest in which of the following biomes?

northern coniferous forest

Coral reefs can be found on the southeast coast of the United States but not at similar latitudes on the southwest coast. Differences in which of the following most likely account for this?

ocean currents

Water responds to the osmolarity gradient by moving from an area of lower solute concentration to an area of higher solute concentration--a process called

osmosis

Osmosis does not require energy. For this reason, osmosis is a form of

passive transport

Trees are not usually found in the tundra biome because of

permafrost

What is the limiting factor for the growth of trees in the tundra?

permafrost

Which hormone stimulates milk production?

prolactin

Parts of the kidney

renal cortex renal medulla ureter

Generalized global air circulation and precipitation patterns are caused by

rising, warm, moist air masses that cool and release precipitation as they rise and then, at high altitude, cool and sink back to the surface as dry air masses after moving north or south of the tropics.

Animals can be classified according to their mode of thermoregulation. Sort the animals below, indicating their likely thermoregulatory strategy. poikilothermic ectotherm

salamander, butterfly, freshwater catfish

Which of the biomes—tundra, coniferous forest, temperate broadleaf forest, temperate grassland, savanna, chaparral, desert, tropical rainforest—require periodic fires to maintain their existence?

savanna, chaparral, temperate grassland, and coniferous forest

The movement of substances from the blood into the proximal tubule is known as _____.

secretion

Which component of a homeostatic system perceives changes in some parameter of the environment?

sensor

Which of the following actions acts to warm a homeothermic body?

shivering

____ muscle is attached to the bones

skeletal

What type of muscle is responsible for contractions of the digestive tract and arteries?

smooth muscle

Which of these is reabsorbed from filtrate?

sodium chloride glucose water amino acids

The main reason that polar regions are cooler than the equator is that

sunlight strikes polar regions at a lower angle.

In mountainous areas of western North America, north-facing slopes would be expected to

support biological communities similar to those found at higher elevations on similar south-facing slopes.

Imagine some cosmic catastrophe jolts Earth so that its axis is perpendicular to the orbital plane between Earth and the sun. The most obvious effect of this change would be

the elimination of seasonal variation.

Steroid hormone-receptor complexes act in _____.

the nucleus

The primary reason steroid hormones usually act slowly is that _____.

they turn genes on or off and it takes time for gene products to build up or become depleted

nervous tissue functions

to sense stimuli

True or false? Organisms must maintain homeostasis because optimal enzyme activity is achieved within a very narrow range of conditions.

true

The osmolarity gradient is also maintained by the passive transport of

urea

Animals can be classified according to their mode of thermoregulation. Sort the animals below, indicating their likely thermoregulatory strategy. homeothermic endotherm

walrus, eagle, coyote

In most cases, the two major climatic factors affecting the distribution of organisms in terrestrial ecosystems are __________.

water and temperature

Which of the following would increase the rate of heat exchange between an animal and its environment?

wind blowing across the body surface