chapter 3 key terms

Question 1

light microscope

Answer 1

light passes through one or more lenses to produce an enlarged image of a specimen

Question 2

electron microscope

Answer 2

forms an image of a specimen using a beam of electrons

Question 3

magnification

Answer 3

the ability to make an image appear larger than its actual size

Question 4

resolution

Answer 4

a measure of the clarity of an image

Question 5

scanning tunneling microscope

Answer 5

uses a needle-like probe to measure differences in voltage caused by electrons that leak, or tunnel, from the surface of the object being viewed

Question 6

cell theory

Answer 6

1. All living things are made of one or more cells.

Question 7

cell membrane

Answer 7

the outer boundary of a cell, can also be called the plasma membrane

Question 8

cytoplasm

Answer 8

the interior of the cell, inside cytoplasm are many structures

Question 9

cytoskeleton

Answer 9

a suspended system of microscopic fibers within the cytoplasm

Question 10

prokaryote

Answer 10

the smallest and simplest cells, its a single-celled organism that has no nucleus and other internal compartments

Question 11

cell wall

Answer 11

a wall that surrounds only bacterial cell membranes, animal cells do NOT have cell walls, it provides structure and support

Question 12

flagella

Answer 12

long, threadlike structures that protrude from the cell’s suface and enable movement

Question 13

eukaryote

Answer 13

an organism whose cells do have a nucleus

Question 14

nucleus

Answer 14

internal compartment that houses the cell’s DNA

Question 15

organelle

Answer 15

a structure that carries out specific activities in the cell

Question 16

cilia

Answer 16

short hairlike structures that protrude from the surface of some eukaryotic cells, some propel cells through the environment and some move substances along the cell’s surface

Question 17

phospholipid

Answer 17

a lipid made of the phosphate group and 2 fatty acids, it has a polar “head” and 2 non-polar “tails”

Question 18

polar

Answer 18

attracted to water (phosphate group)

Question 19

nonpolar

Answer 19

repels water

Question 20

lipid bilayer

Answer 20

a double layer within the cell membrane

Question 21

endoplasmic reticulum

Answer 21

an extensive system of internal membranes that move proteins and other substances through the cell

Question 22

vesicle

Answer 22

a small, membrane-bound sac that transports substances within cells

Question 23

Golgi apparatus

Answer 23

a set of flattened, membrane-bound sacs that serve as the packaging and distribution center of the cell

Question 24

lysosomes

Answer 24

small, spherical organelles that contain the cell’s digestive enzymes, work with the endoplasmic reticulum and Golgi apparatus

Question 25

mitochondria

Answer 25

an organelle that harvests energy from organic compounds to make ATP, is contained within eukaryotic cells

Question 26

chloroplasts

Answer 26

organelles in plants that use light energy to make carbohydrates from carbon dioxide and water

Question 27

central vacuole

Answer 27

membrane-bound space within cells, they are found in both plant and animal cells, only plant cells contain a central vacuole