cell biology review (ch 2)

Question 1

what is the cell membrane?

Answer 1

Phospholipid bilayer containing cholesterol, proteins (integral and peripheral), and some carbohydrates (externally)

Question 2

function of cell membrane?

Answer 2

Contains receptors for communication; forms intercellular connections; acts as physical barrier to enclose cell contents; regulates material movement into and out of the cell

Question 3

what is cytoplasm?

Answer 3

Contains cytosol (a viscous fluid), inclusions, and organelles

Question 4

function of cytoplasm?

Answer 4

Place of many metabolic processes of the cell; stores nutrients and dissolved solutes

Question 5

what is the cytoskeleton?

Answer 5

Network of filaments and microtubules

Question 6

function of cytoskeleton?

Answer 6

Provides structural support; helps cellular movement, transport of materials,

Question 7

what is the mitochondria?

Answer 7

Double membrane structures with cristae; fluid matrix contents at center

Question 8

function of mitochondria?

Answer 8

Synthesize most ATP during cellular respiration; “powerhouses of cell”

Question 9

what is the rough endoplasmic reticulum?

Answer 9

membranous stacks called cisternae, has ribosomes

Question 10

function of rough ER?

Answer 10

involved in the synthesis of protein secretion granules and lysosomes

Question 11

what is the smooth ER?

Answer 11

membrane tubules

Question 12

function of smooth ER?

Answer 12

mediates detoxification of poisons,

metabolizes lipids and sugars, and stores calcium ions

Question 13

what is the golgi apparatus?

Answer 13

Stacked series of flattened, smooth membrane sacs with associated transport vesicles

Question 14

function of golgi apparatus?

Answer 14

Modifies, packages, and sorts newly synthesized proteins

“go-gee”: tells proteins to “go!”

Question 15

what are secretion granules?

Answer 15

Secretory granules contain specific proteins and other macromolecules that are destined for secretion into the extracellular space.

Question 16

what are lysosomes?

Answer 16

Membrane sacs with digestive enzymes

Question 17

function of lysosomes?

Answer 17

Digest materials or microbes ingested by the cell; remove old/damaged organelles

Question 18

what are centrioles?

Answer 18

Paired perpendicular cylindrical bodies; composed of microtubule triplets

Question 19

function of centrioles?

Answer 19

Organize microtubules during cell division for movement and separation of chromosomes

Question 20

what is the nucleus?

Answer 20

Surrounded by double membrane nuclear envelope (each membrane is a phospholipid bilayer); contains nucleolus and chromatin within nucleoplasm (a fluid)

Question 21

function of nucleus?

Answer 21

houses genetic information (DNA); site of ribosome subunit assembly

Question 22

what is the nuclear envelope with pores?

Answer 22

Double membrane boundary between cytoplasm and nuclear contents

Question 23

function of nuclear envelope?

Answer 23

Physical barrier that controls movement of materials between the nucleus and the cytoplasm

Question 24

what is chromatin?

Answer 24

material that chromosomes of organisms other than bacteria (i.e., eukaryotes) are composed. It consists of protein, RNA, and DNA.

Question 25

function of chromatin?

Answer 25

Site of genes in the DNA

Question 26

what is the nucleolus?

Answer 26

• area inside the nucleus of a cell that is made up of RNA

- where ribosomes are made

Question 27

function of nucleolus?

Answer 27

Synthesizes rRNA and assembles ribosomes in the nucleus

Question 28

what is a chromosome?

Answer 28

The most organized level of genetic material; a single long molecule of DNA and associated proteins; becomes visible only when cell is dividing.

Question 29

function of a chromosome?

Answer 29

make sure DNA is replicated and distributed evenly across cell

Question 30

what is exocytosis?

Answer 30

aka cell secretion; large molecules move out of the cell using vesicles

Question 31

what are the three forms of endocytosis?

Answer 31

phago-, pino- and receptor-mediated

Question 32

what is endocytosis?

Answer 32

Bulk movement of substances into a cell by vesicles forming at the plasma membrane

Question 33

what is phagocytosis?

Answer 33

Type of endocytosis in which particulate materials move into a cell after being engulfed by pseudopodia at the cell surface; vesicles form at the inside of the plasma membrane
*Think “phago equals pseudo”

Question 34

what is pinocytosis?

Answer 34

the ingestion of liquid into a cell by the budding of small vesicles from the cell membrane.
phago = solid, pino = liquid

Question 35

what is receptor-mediated endocytosis?

Answer 35

Type of endocytosis in which specific molecule-receptor complexes in the plasma membrane stimulate the clustering of bound molecule-receptor complexes

Question 36

what are the three elements of the cytoskeleton?

Answer 36

microfilaments, microtubules, intermediate filaments

Question 37

process of secretion granule release is ____

Answer 37

exocytosis

Question 38

where does the golgi receive proteins from?

Answer 38

from rough ER