Chapter 40 - Basic Principles of Animal Form and Function

Question 1

thermoregulation

Answer 1

The maintenance of internal body temperature within a tolerable range.

Question 2

endothermic

Answer 2

Referring to organisms that are warmed by heat generated by their own metabolism. This heat usually maintains a relatively stable body temperature higher than that of the external environment.

Question 3

ectothermic

Answer 3

Referring to organisms for which external sources provide most of the heat for temperature regulation.

Question 4

integumentary system

Answer 4

The outer covering of a mammal’s body, including skin, hair, and nails, claws, or hooves.

Question 5

countercurrent exchange

Answer 5

The exchange of a substance or heat between two fluids flowing in opposite directions. For example, blood in a fish gill flows in the opposite direction of water passing over the gill, maximizing diffusion of oxygen into and carbon dioxide out of the blood.

Question 6

hypothalamus

Answer 6

The ventral part of the vertebrate forebrain; functions in maintaining homeostasis, especially in coordinating the endocrine and nervous systems; secretes hormones of the posterior pituitary and releasing factors that regulate the anterior pituitary.

Question 7

bioenergetics

Answer 7

(1) The overall flow and transformation of energy in an organism. (2) The study of how energy flows through organisms.

Question 8

metabolic rate

Answer 8

The total amount of energy an animal uses in a unit of time.

Question 9

basal metabolic rate (BMR)

Answer 9

The metabolic rate of a resting, fasting, and nonstressed endotherm at a comfortable temperature.

Question 10

standard metabolic rate (SMR)

Answer 10

Metabolic rate of a resting, fasting, and nonstressed ectotherm at a particular temperature

Question 11

torpor

Answer 11

A physiological state in which activity is low and metabolism decreases.

Question 12

hibernation

Answer 12

A long-term physiological state in which metabolism decreases, the heart and respiratory system slow down, and body temperature is maintained at a lower level than normal.

Question 13

anatomy

Answer 13

The structure of an organism

Question 14

physiology

Answer 14

The process and functions of an organism.

Question 15

interstitial fluid

Answer 15

The fluid filling the spaces between cells in most animals.

Question 16

tissue

Answer 16

An integrated group of cells with a common structure, function, or both.

Question 17

organ

Answer 17

A specialized center of body function composed of several different types of tissues.

Question 18

organ system

Answer 18

A group of organs that work together in performing vital body functions.

Question 19

epithelial tissue

Answer 19

Sheets of tightly packed cells that line organs and body cavities as well as external surfaces.

Question 20

connective tissue

Answer 20

Animal tissue that functions mainly to bind and support other tissues, having a sparse population of cells scattered through an extracellular matrix.

Question 21

fibroblast

Answer 21

A type of cell in loose connective tissue that secretes the protein ingredients of the extracellular fibers.

Question 22

macrophage

Answer 22

A phagocytic cell present in many tissues that functions in innate immunity by destroying microbes and in acquired immunity as an antigen-presenting cell.

Question 23

tendon

Answer 23

A fibrous connective tissue that attaches muscle to bone.

Question 24

ligament

Answer 24

A fibrous connective tissue that joins bones together at joints.

Question 25

bone

Answer 25

A connective tissue consisting of living cells held in a rigid matrix of collagen fibers embedded in calcium salts.

Question 26

adipose tissue

Answer 26

A connective tissue that insulates the body and serves as a fuel reserve; contains fat-storing cells called adipose cells.

Question 27

cartilage

Answer 27

A flexible connective tissue with an abundance of collagenous fibers embedded in chondroitin sulfate.

Question 28

blood

Answer 28

A connective tissue with a fluid matrix called plasma in which red blood cells, white blood cells, and cell fragments called platelets are suspended.

Question 29

epithelium

Answer 29

An epithelial tissue.

Question 30

muscle tissue

Answer 30

Tissue consisting of long muscle cells that can contract, either on its own or when stimulated by nerve impulses.

Question 31

skeletal muscle

Answer 31

A type of striated muscle that is generally responsible for the voluntary movement of the body.

Question 32

smooth muscle

Answer 32

A type of muscle lacking the striations of skeletal and cardiac muscle because of the uniform distribution of myosin filaments in the cells; responsible for involuntary body activities.

Question 33

cardiac muscle

Answer 33

A type of striated muscle that forms the contractile wall of the heart. Its cells are joined by intercalated disks that relay the electrical signals underlying each heartbeat.

Question 34

nervous tissue

Answer 34

Tissue made up of neurons and supportive cells.

Question 35

neuron

Answer 35

A nerve cell; the fundamental unit of the nervous system, having structure and properties that allow it to conduct signals by taking advantage of the electrical charge across its plasma membrane.

Question 36

glia (glial cells)

Answer 36

Cells of the nervous system that support, regulate, and augment the functions of neurons.

Question 37

hormone

Answer 37

In multicellular organisms, one of many types of secreted chemicals that are formed in specialized cells, travel in body fluids, and act on specific target cells in other parts of the body, changing target cells’ functioning. Hormones are thus important in long-distance signaling.

Question 38

regulator

Answer 38

An animal for which mechanisms of homeostasis moderate internal changes in a particular variable in the face of external fluctuation of that variable.

Question 39

conformer

Answer 39

An animal for which an internal condition conforms to (changes in accordance with) changes in an environmental variable.

Question 40

homeostasis

Answer 40

The steady-state physiological condition of the body.

Question 41

set point

Answer 41

In homeostasis in animals, a value maintained for a particular variable, such as body temperature or solute concentration.

Question 42

stimulus

Answer 42

In feedback regulation, a fluctuation in a variable that triggers a response.

Question 43

sensor

Answer 43

In homeostasis, a receptor that detects a stimulus.

Question 44

response

Answer 44

(1) In cellular communication, the change in a specific cellular activity brought about by a transduced signal from outside the cell. (2) In feedback regulation, a physiological activity triggered by a change in a variable.

Question 45

negative feedback

Answer 45

A form of regulation in which accumulation of an end product of a process slows the process; in physiology, a primary mechanism of homeostasis, whereby a change in a variable triggers a response that counteracts the initial change.

Question 46

positive feedback

Answer 46

A form of regulation in which an end product of a process speeds up that process; in physiology, a control mechanism in which a change in a variable triggers a response that reinforces or amplifies the change.

Question 47

circadian rhythm

Answer 47

A physiological cycle of about 24 hours that persists even in the absence of external cues.

Question 48

acclimatization

Answer 48

Physiological adjustment to a change in an environmental factor.