Chapter 25

Question 1

Homeostasis

Answer 1

Interactions between cells in tissues, organs, and organ systems that keep the operating conditions of the internal environment within tolerable limits.

Question 2

Anatomy

Answer 2

Study of body form, its morphology

Question 3

Physiology

Answer 3

study of patterns and processes by which an individual survives and reproduces in the enviroment

Question 4

Tissue

Answer 4

A community of cells and extracellular substances that interact in one or more tasts

Question 5

Organ

Answer 5

A structural unit made up of tissues arranged in proportions and patterns that allow it to carry out a specific task(s)

Question 6

Organ System

Answer 6

Organs that interact in one or more tasks

Ex. Lungs and airways are organs of the respiratory system of land vertebrates

Question 7

Growth vs Development

Answer 7

Growth - Refers to an increase in the number, size, and volume of cells. Measure in quantitative terms.
Development - Series of stages in which specialized tissues, organs, and organ systems form in heritable patterns. Measure in qualitative terms.

Question 8

Flower

Answer 8

Reproductive organ

Question 9

Respiratory System

Answer 9

Gases only move into and out of an animal by diffusing across a moist surface. Land animals contain moist sacs for gas exchange within the body.

Question 10

Extracellular Fluid and components

Answer 10

Body fluid not inside cells, acts as an internal environment. The body requires a stable fluid environment for its cells.
Interstitial Fluid - Type of extracellular fluid, fills spaces between cells and tissues
Plasma - fluid portion of cells

Question 11

Diffusion

Answer 11

When ions or molecules of a substance are concentrated in one place, they tend to move to a place where they are not as concentrated. Plants and animals keep gases diffusing in directions most suitable for metabolism and cell survival.

Question 12

Vascular Tubes

Answer 12

Systems of tubes through which substances move to and from cells

Question 13

Active Transport

Answer 13

Protein pumps one specific solute from a region of low concentration to one of higher concentration.

Question 14

Signalling Mechanisms

Answer 14

Guide how the plant or animal body grows, develops, and maintains itself, and also reproduces

Question 15

Biotic

Answer 15

Living

Question 16

Sensory receptors

Answer 16

Cells of cell parts that detect stimuli, which are specific forms of energy

Question 17

Integrator

Answer 17

A central command post that receives and processes information about stimuli, issues signals to effectors

Question 18

Effectors

Answer 18

Muscles, glands, or both, that carry out suitable responses to the stimulation

Question 19

Feedback Mechanisms

Answer 19

Major homeostatic controls, help maintain physical and chemical aspects of the body’s internal environment within ranges that its individual cells can operate

Question 20

Negative Feedback Mechanisms

Answer 20

An activity changes a specific condition in the internal environment, and when the condition changes past a point, a response reverses the change

Question 21

Positive Feedback Mechanisms

Answer 21

Mechanisms spark a chain of events that intensify change from an original condition, in a living organism this intensification will lead to a change that ends the feedback

Question 22

System Acquired Resistance

Answer 22

A defence response to infections and injured tissues. Cells in an affected tissue release signalling molecules that call for the synthesis and release of organic compounds that will protect the plant against attacks.

Question 23

Compartmentalization

Answer 23

Trees will wall off the damaged tissue, release phenols (and other toxic compounds) and often secrete resins. Compartments form around injured, infected, or poisoned tissues, and new tissues grow overtop.

Question 24

Leaf folding

Answer 24

A controlled response by Lupinus arboreus to changing conditions. Response minimizes heat absorption.

Question 25

Circadian Rhythm

Answer 25

Biological activity pattern that recurs with an approximate 24-hour cycle. Phytocrome helps control this.

Question 26

Homeostasis in Plants

Answer 26

There are control mechanisms (compartmentalization, system acquired resistance, and rhythmic leaf movements) that help maintain homeostasis, but they are not centrally controlled like in animals.

Question 27

Things involved in Communication Among Distant Cells

Answer 27

Amino acids, peptides, proteins, lipids, and gases. Some other signals diffuse through interstitial fluid, or through blood vessels or vascular tissues.

Question 28

Molecular Mechanisms in Cell Communication

Answer 28

Often have three steps:

1. Specific Receptor is activated
2. Signal is transduced (converted into a form that can operate inside the cell)
3. Cell makes a response to the signal (ex. altering its metabolism or which genes it expresses)

Question 29

Responses to Molecular Signals

Answer 29

Many receptors that respond are membrane proteins, and once activated some will activate an enzyme that will activate more of a different kind of enzyme, and so on.

Question 30

Cascading Reactions

Answer 30

Amplify the response to one signal many times over

Question 31

Apoptosis

Answer 31

The process of programmed cell death. Example of a response to signal reception.