Chapter 7

Question 1

Basic unit of all forms of life

Answer 1

Cell

Question 2

Fundamental concept of biology that states that all living things are composed of cells; that cells are the basic unit of structure and function in living things; and that new cells are produced from existing cells.

Answer 2

Cell theory

Question 3

Thin, flexible barrier that surrounds all cells; regulates what enters and leaves the cell

Answer 3

Cell membrane

Question 4

The center of an atom, which contains the protons and neutrons; in cells, structure that contains the cell’s genetic material in the form of DNA.

Answer 4

Nucleus

Question 5

Organism whose cells contain a nucleus

Answer 5

Eukaryotes

Question 6

Unicellular organism that lacks a nucleus

Answer 6

Prokaryote

Question 7

In eukaryotic cells, all cellular contents outside the nucleus; in prokaryotic cells, all of the cells’ contents.

Answer 7

Cytoplasm

Question 8

Specialized structure that performs important cellular functions within a cell

Answer 8

Organelle

Question 9

Cell organelle that stores materials such as water, salts, proteins, and carbohydrates

Answer 9

Vacuole

Question 10

Cell organelle that breaks down lipids, carbohydrates, and proteins into small molecules that can used by the rest of the cell

Answer 10

Lysosome

Question 11

Network of roots in filaments in a eukaryotic cell that gives the cell its shape and internal organization and is involved in movement

Answer 11

Cytoskeleton

Question 12

Structure in an animal cell that helps to organize cell division.

Answer 12

Centriole

Question 13

Cell organelle consisting of RNA and protein found throughout the cytoplasm in a cell; the site of protein synthesis

Answer 13

Ribosome

Question 14

Internal membrane system found in eukaryotic cells; place where lipid components of the cell membrane are assembled

Answer 14

Endoplasmic reticulum

Question 15

Organelle in cells that modifies, sorts, and packages proteins and other materials from the endoplasmic reticulum for storage in the cell or release outside the cell

Answer 15

Golgi apparatus

Question 16

Organelle found in cells of plants and some other organisms that captures the energy from sunlight and converts it into chemical energy

Answer 16

Chloroplast

Question 17

Cell organelle that converts the chemical energy stored in food into compounds that are more convenient fur the cell to use

Answer 17

Mitochondria

Question 18

Strong, supporting layer around the cell membrane in some cells

Answer 18

Cell wall

Question 19

Flexible double-layered sheet that makes u the cell membrane and forms a barrier between the cell and its surroundings

Answer 19

Lipid bilayer

Question 20

Property of biological membranes that allows some substances to pass across it while others cannot; also called semipermeable membrane

Answer 20

Selectively permeable

Question 21

Process by which particles tend to move from an area where they are more concentrated to an area where they are less concentrated

Answer 21

Diffusion

Question 22

Process of diffusion in which molecules pass across the membrane through the cell membrane channels

Answer 22

Facilitated diffusion

Question 23

Water channel protein in a cell

Answer 23

Aquaporin

Question 24

Diffusion of water through a selectively permeable membrane

Answer 24

Osmosis

Question 25

When the concentration of two solutions us the same

Answer 25

Isotonic

Question 26

When comparing two solutions, the solution with the greater concentration of so lutes

Answer 26

Hypertonic

Question 27

When comparing two solutions, the solution with the lesser concentration of salutes

Answer 27

Hypotonic

Question 28

Pressure that must be applied to prevent osmotic movement across a selectively permeable membrane

Answer 28

Osmotic pressure

Question 29

Relatively constant internal physical and chemical conditions that organisms maintain

Answer 29

Homeostasis

Question 30

Group of similar cells that perform a particular function

Answer 30

Tissue

Question 31

Group of tissues that work together to perform closely related functions

Answer 31

Organ

Question 32

Group of organs that work together to perform a special function

Answer 32

Organ system

Question 33

On or in a cell, a specific protein to whose shape fits that of a specific molecular messenger, such as a hormone

Answer 33

Receptor