bio Chapter 40

homeostasis

"steady state" referring to the maintenance of internal balance

3 types of connective tissue fibers

1. collagenous fibers 2. reticular fibers 3. elastic fibers

4 types of animal tissue

1. epithelial 2. connective 3. muscle 4. nervous

3 types of muscle tissue`

1. skeletal 2. smooth 3. cardiac

Most land-dwelling invertebrates and all of the amphibians _____. A) are ectothermic organisms with variable body temperatures B) alter their metabolic rates to maintain a constant body temperature of 37°C C) are endotherms but become thermoconformers when they are in water D) become more active when environmental temperatures drop below 15°C

A) are ectothermic organisms with variable body temperatures

You discover a new species of bacteria that grows in aquatic environments with high salt levels. While studying these bacteria, you note that their internal environment is similar to the salt concentrations in their surroundings. You also discover that the internal salt concentrations of the bacteria change as the salt concentration in their environment changes. The new species can tolerate small changes in this way, but dies from large changes because it has no mechanism for altering its own internal salt levels. What type of homeostatic mechanism is this species using to regulate its internal salt levels? A) conformation B) regulation C) integration D) assimilation

A) conformation

A woman standing and watching the stars on a cool, calm night will lose most of her body heat by _____. A) radiation B) convection C) conduction D) evaporation

A) radiation

An example of an ectothermic organism that has few or no behavioral options when it comes to its ability to adjust its body temperature is a _____. A) sea star living deep in the ocean B) bass living in a farm pond C) hummingbird flying through a prairie D) honeybee in a hive on a rural farm

A) sea star living deep in the ocean

) Examine the figure above. Near a goose's abdomen, the countercurrent arrangement of the arterial and venous blood vessels causes the _____. A) temperature difference between the contents of the two sets of vessels to be minimized B) venous blood to be as cold near the abdomen as it is near the feet C) blood in the feet to be as warm as the blood in the abdomen D) loss of the maximum possible amount of heat to the environment

A) temperature difference between the contents of the two sets of vessels to be minimized

What is an example of negative feedback?

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

The temperature-regulating center of vertebrate animals is located in the _____. A) thyroid gland B) hypothalamus C) subcutaneous layer of the skin D) liver

B) hypothalamus

An example of a properly functioning homeostatic control system is seen when _____. A) the core body temperature of a runner rises gradually from 37°C to 45°C B) the kidneys excrete salt into the urine when dietary salt levels rise C) a blood cell shrinks when placed in a solution of salt and water D) the blood pressure increases in response to an increase in blood volume

B) the kidneys excrete salt into the urine when dietary salt levels rise

Positive feedback differs from negative feedback in that _____. A) positive feedback benefits the organism, whereas negative feedback is detrimental B) the positive feedback's effector responses are in the same direction as the initiating stimulus rather than opposite of it C) the effector's response increases some parameter (such as body temperature), whereas in negative feedback it can only decrease the parameter D) positive feedback systems have only effectors, whereas negative feedback systems have only receptors

B) the positive feedback's effector responses are in the same direction as the initiating stimulus rather than opposite of it

Which principle of heat exchange is the most important explanation for why birds look larger in colder weather because they fluff their feathers? A) Fluffing feathers results in less cooling by radiation because feathers emit less infrared radiation than other tissues do. B) Fluffing decreases the amount of heat lost by conduction when the bird makes contact with cold objects in its environment. C) Fluffing creates a pocket of air near the bird that acts as insulation. D) Fluffing decreases the surface-area-to-volume ratio, thus decreasing the amount of heat lost to the environment.

C) Fluffing creates a pocket of air near the bird that acts as insulation.

You are studying a large tropical reptile that has a high and relatively stable body temperature. How would you determine whether this animal is an endotherm or an ectotherm? A) You know from its high and stable body temperature that it must be an endotherm. B) You know that it is an ectotherm because it is not a bird or mammal. C) You subject this reptile to various temperatures in the lab and find that its body temperature and metabolic rate change with the ambient temperature. You conclude that it is an ectotherm. D) You note that its environment has a high and stable temperature. Because its body temperature matches the environmental temperature, you conclude that it is an ectotherm

C) You subject this reptile to various temperatures in the lab and find that its body temperature and metabolic rate change with the ambient temperature. You conclude that it is an ectotherm.

Chum salmon (Oncorhynchus keta) are born in freshwater environments and then migrate to the sea. Near the end of their lives, they return to the freshwater stream where they were born to spawn. In freshwater, water constantly diffuses into the body and ions are lost from the body. In salt water, body water diffuses out of the body and excess ions are gained from the water. A salmon's gills have special cells to pump salt in or out of the body to maintain homeostasis. In response to the salmon's moves between freshwater and salt water, some cells in the gills are produced and others are destroyed. These changes made in the cells of the gills during the lifetime of an individual salmon are an example of which of the following? A) evolution B) trade-off C) acclimatization D) adaptation

C) acclimatization

The body's automatic tendency to maintain a constant and optimal internal environment is termed _____. A) balanced equilibrium B) physiological chance C) homeostasis D) static equilibrium

C) homeostasis

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 _____. A) maintains a higher basal metabolic rate B) expends more energy per kilogram of body mass than does the endotherm C) invests little energy in temperature regulation D) has greater insulation on its body surface

C) invests little energy in temperature regulation

The metabolic breakdown of specialized brown fat depots in certain animals is substantially increased during _____. A) acclimatization B) torpor C) nonshivering thermogenesis D) shivering thermogenesis

C) nonshivering thermogenesis

To prepare flight muscles for use on a cool morning, hawkmoths _____. A) relax the muscles completely until after they launch themselves into the air B) decrease their standard metabolic rate C) rapidly contract and relax these muscles to generate metabolic warmth D) reduce the metabolic rate of the muscles to rest them before flight

C) rapidly contract and relax these muscles to generate metabolic warmth

The thin horizontal arrows in the figure above show that the _____. A) warmer arterial blood can bypass the legs as needed, when the legs are too cold to function well B) warmer venous blood transfers heat to the cooler arterial blood C) warmer arterial blood transfers heat to the cooler venous blood D) arterial blood is always cooler in the abdomen, compared to the temperature of the venous blood in the feet of the goose

C) warmer arterial blood transfers heat to the cooler venous blood

Which of the following would increase the rate of heat exchange between an animal and its environment? A) feathers or fur B) vasoconstriction C) wind blowing across the body surface D) blubber or fat layer

C) wind blowing across the body surface

How does connective tissue differ from the other three major tissue types?

Connective tissue often consists of relatively few cells embedded in an extracellular matrix.

Which of the following is an example of negative feedback? A) During birthing contractions, oxytocin (a hormone) is released and acts to stimulate further contractions. B) When a baby is nursing, suckling leads to the production of more milk and a subsequent increase in the secretion of prolactin (a hormone that stimulates lactation). C) After a blood vessel is damaged, signals are released by the damaged tissues that activate platelets in the blood. These activated platelets release chemicals that activate more platelets. D) When the level of glucose in the blood increases, the pancreas produces and releases the hormone insulin. Insulin acts to decrease blood glucose. As blood glucose decreases, the rate of production and release of insulin decreases as blood glucose decreases.

D) When the level of glucose in the blood increases, the pancreas produces and releases the hormone insulin. Insulin acts to decrease blood glucose. As blood glucose decreases, the rate of production and release of insulin decreases as blood glucose decreases.

There are advantages and disadvantages to adaptations. Animals that are endothermic are likely to be at the greatest disadvantage in _____. A) very cold environments B) very hot environments C) environments with a constant food source D) environments with variable and limited food sources

D) environments with variable and limited food sources

Sweating allows a person to lose heat through the process of _____. A) conduction B) convection C) radiation D) evaporation

D) evaporation

The panting responses that are observed in overheated birds and mammals dissipate excess heat by _____. A) countercurrent exchange B) acclimation C) vasoconstriction D) evaporation

D) evaporation

Snake behavior in Wisconsin changes throughout the year. For example, a snake is _____. A) less active in winter because the food supply is decreased B) less active in winter because it does not need to avoid predators C) more active in summer because that is the period for mating D) more active in summer because it can gain body heat by conduction

D) more active in summer because it can gain body heat by conduction

A moth preparing for flight on a cold morning may warm its flight muscles via _____. A) acclimatization B) torpor C) evaporative cooling D) shivering thermogenesis

D) shivering thermogenesis

Which component of a homeostatic system sends instructions based on sensory information?

Integrator

What describes loose connective tissue?

It is a loose weave of fibers that functions as a packing material.

positive feedback

a control mechanism that amplifies the stimulus

negative feedback

a control mechanism that reduces the stimulus

vasoconstriction

a decrease in the diameter of superficial vessels that reduces blood flow and heat transfer

hibernation

a long term torpor that is an adaptation to winter cold and food scarcity

bone

a mineralized connective tissue

torpor

a physiological state of decreased activity and metabolism. an adaptation that enables animals to save energy while avoiding difficult and dangerous conditions

cardiac rhythm

a set of physiological changes that occur every 24 hours

adipose tissue

a specialized loose connective tissue that stores fat in adipose cells

muscle tissue

a tissue that is responsible for all types of body movement

vasodilation

a widening of superficial blood vessels

conformer

allows its internal condition to change in accordance with external changes in the variable

poikilotherm

an animal who's body temp varies with its environment

homeotherm

animals that have a constant body temperature

Cartilage is found _____.

at the end of each bone

tendon

attached muscle to bones

skeletal muscle

attached to bones by tendons is responsible for voluntary movements also called striated muscle

anatomy

biological form

physiology

biological function

_____ is the connective tissue specialized for transport.

blood

Cardiac muscle is the only muscle composed of _____ fibers.

branched

fibroblasts

cells within the matrix that secrete fiber proteins

ligament

connects bones at joints

cartilage

contains collagenous fibers embedded in a matrix

hypothalmus

contains the sensors for thermoregulation and also the circadian clock

epithelial tissue

cover the outside of the body and line organs and cavities within the body. closely packed cells

A neuron consists of _____.

dendrites, a cell body, and axons

bioenergetics

determines nutritional needs and is related to the animals size, activity, and environment

cuboidal epithelium

dice shaped cells specialized for secretion

organs

different types of tissue that are organized into functional units

macrophages

engulf foreign particles and nay cell debris by phagocytosis

interstitial fluid

fluid that fills the space between cells

cardiac muscle

forms the contractile wall of the heart

nervous tissue

functions in the receipt, processing, and transmission of information

tissue

groups of cells with similar appearances and a common function

organ system

groups of organs that work together and provide an additional level of organization

blood

has a liquid extracellular matrix called plasma

glia cells

help nourish, insulate, and replenish neurons

connective tissue

holds many tissues and organs together and in place

endothermic

humans and other mammals (birds too) that are warmed mostly by heat generated by their metabolism

reticular fibers

join connective tissue to adjacent tissue

smooth muscle

lacks striation and is found in the walls of the digestive tract, urinary bladder, arteries, and other internal organs.

simple columnar epithelium

large brick shaped cells found where secretion or active absorption is important

elastic fibers

make tissue elastic

stratified squamous epithelium

multilayered and regenerate rapidly, commonly found on surfaces like skin

nervous system

neurons transmit signals along dedicated routes connecting specific locations in the body

ectothermic

nonvertebrates and reptiles that gain most of their heat from external sources

collagenous fibers

provides strength and flexibility

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

sensor

Which action acts to warm a homeothermic body?

shivering

endocrine system

signaling molecules released into the blood stream by endocrine cells are carried to all locations in the body

hormones

signaling molecules that broadcast throughout the body by the endocrine system

What type of epithelial tissue, found in the intestines, absorbs nutrients?

simple columnar epithelium

What type of epithelial tissue lines kidney tubules?

simple cuboidal cells

What tissue, found in the lungs, permits gas exchange by diffusion?

simple squamous epithelium

pseudo stratified columnar epithelium

single layer of cells varying in height and the position of their nuclei

simple squamous epithelium

single layer of platelike cells that function in the exchange of material by diffusion

_____ muscle is attached to bones.

skeletal

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

smooth muscle

What type of epithelium would you expect to find covering a surface subject to physical forces?

stratified epithelium

acclimatization

the gradual process by which an animal adjusts to changes in its external environment

standard metabolic rate (SMR)

the metabolic rate of a fasting non stressed ectotherm at rest at particular temperature

basal metabolic rate (BMR)

the minimum metabolic rate of a non growing endotherm that is at rest, has an empty stomach, and is not experiencing stress

integumentary system

the other covering of the body, consisting of the skin, hair, and nails

thermoregulation

the process by which animals maintain their body temperature within a normal range

metabolic rate

the sum of all energy an animal uses in a given time interval

contercurrent exchange

the transfer of heat or solutes between fluids that are flowing in opposite directions

Nervous tissue functions _____.

to sense stimuli

neurons

transmit nerve impulses as wells as support glial cells

regulator

uses internal mechanisms to control internal changes in the face of external fluctuation