Ch 4

Question 1

eukaryotic cells

Answer 1

contain a membrane bound nucleus

Question 2

eukaryotes

Answer 2

10-100 micrometers, contain a nucleus and organelles, undergo mitosis/meiosis, have extensive RNA processing, use endo and exocytosis

Question 3

prokaryotes

Answer 3

1-5 micrometers, no nucleus or organelles, undergo binary fission, minimal RNA processing

Question 4

cell size limitations

Answer 4

1. adequate surface area to volume ratio
2. molecule diffusion rate
3. must maintain local concentrations of substances

Question 5

microvilli

Answer 5

fingerlike projections that increase surface area

Question 6

diffusion

Answer 6

unassisted movement according to concentration gradient

Question 7

nucleoid

Answer 7

compact structure of folded DNA attached to cell membrane

Question 8

components of a eukaryotic cell

Answer 8

plasma membrane, nucleus, membrane bound organelles, cytosol, and cytoskeleton

Question 9

additional components of plant and fungal cells

Answer 9

rigid cell wall surrounded by EC matrix

Question 10

nucleus

Answer 10

largest eukaryotic structure

Question 11

mitochondria

Answer 11

degrades sugars and fatty acids, generates ATP; aids in calcium buffering

Question 12

cristae

Answer 12

infoldings of mitochondrial membrane

Question 13

chloroplast

Answer 13

site of photosynthesis

Question 14

thylakoids

Answer 14

flattened membranous sacs which make up chloroplasts

Question 15

grana

Answer 15

stacked thylakoids

Question 16

stroma

Answer 16

semifluid in the interior of the chloroplast

Question 17

endosymbiont theory

Answer 17

mitochondria and chloroplasts were derived from bacteria

Question 18

endomembrane system

Answer 18

synthesizes proteins destined for various organelles, cellular membranes, or secretion

Question 19

cisternae

Answer 19

flattened sacs in the endoplasmic reticulum

Question 20

rough ER

Answer 20

contains ribosomes on cytoplasmic side of membrane; functions in secretory protein synthesis

Question 21

smooth ER

Answer 21

involved in synthesis of lipids and steroids; inactivates and detoxifies

Question 22

sarcoplasmic reticulum

Answer 22

contraction

Question 23

golgi apparatus

Answer 23

processes and packages secretory proteins; synthesizes complex polysaccharides

Question 24

secretory vessels

Answer 24

move to plasma membrane and fuse with it, allowing contents to be released to outside of cell

Question 25

lysosome

Answer 25

single-membrane organelle; contains hydrolases

Question 26

hydrolase

Answer 26

enzymes that digest biological molecules

Question 27

peroxisomes

Answer 27

similar to lysosomes; prominent in liver and kidney cells

Question 28

glyoxysomes

Answer 28

peroxisomes in plants that convert stored fat into carbs

Question 29

leaf peroxisomes

Answer 29

play a role in photorespiration

Question 30

photorespiration

Answer 30

light-dependent uptake of oxygen and release of carbon dioxide

Question 31

vacuole

Answer 31

used for temporary storage or transport

Question 32

central vacuole

Answer 32

maintains turgor pressure that keeps plant from wilting

Question 33

ribosomes

Answer 33

site of protein synthesis

Question 34

cytoskeleton

Answer 34

gives cell distinctive shape and organization

Question 35

extracellular matrix

Answer 35

structures that give physical support

Question 36

cell walls

Answer 36

ECM of plant cells

Question 37

motility

Answer 37

movement of plant cells made possible by elastic network of collagen fibers

Question 38

plasmodesmata

Answer 38

cytoplasmic bridges which connect neighboring plant cells