Cell components

Question 1

Nucleoid

Answer 1

region where prokaryotic cells DNA is located with no membrane

Question 2

Nuclear envelope

Answer 2

double membrane for the nucleus nuclear pores dotted throughout

Question 3

nuclear lamina

Answer 3

on the nuclear side a netlike array of protein filaments that maintains the shape of the nucleus

Question 4

chromatin

Answer 4

complex of proteins and DNA

Question 5

free ribosomes

Answer 5

cytosolic ribosomes that make proteins such as enzyme in sugar catabolism in cytosol

Question 6

Bound ribosomes

Answer 6

ribosomes that are bound to the surface of the nuclear lamina or ER for secretion

Question 7

endomembrane system

Answer 7

membrane organelles interact in the transport of molecules by vesicles

Question 8

ER lumen

Answer 8

the space between nuclear membranes is continuous to the ER lumen

Question 9

smoother ER

Answer 9

synthesis of lipids, metabolism of carbohydrates, detoxification of drugs and poisons depending on which organ they are present

Question 10

Carbohydrate addition

Answer 10

carbohydrates are first added to proteins in the ER

Question 11

golgi apparatus

Answer 11

modifies the phospholipids and proteins and readies them for secretion

Question 12

lysosome

Answer 12

membranous sac of hydrolytic enzymes that either break down food particles by phagocytosis or damaged organelle

Question 13

food vacuoles

Answer 13

protists use phagocytosis and lysosomes to digest smaller organisms

Question 14

contractile vacuole

Answer 14

freshwater protists use this to pump excess water out of the cell

Question 15

central vacuole

Answer 15

in mature plants this stores water and nutrients and allows growth of the cell without expanse of the cytoplasm

Question 16

tonoplast

Answer 16

membrane that surrounds the central vacuole

Question 17

peroxisome

Answer 17

do not bud from the ER membrane system but grow larger by adding lipids and proteins from cytosol

Question 18

cytoskeleton structures

Answer 18

microtubules, microfilaments, and intermediate filaments

Question 19

motor proteins

Answer 19

cytoskeletal elements move motor proteins with vesicles or other proteins throughout the cell or even vesicles with neurotransmitters

Question 20

microtubules

Answer 20

largest; hollow tubes; cilia/flagella motility; compression resistance; organelle movements; chromosome retraction during cell division

Question 21

microfilaments

Answer 21

smallest; actin filaments; tension bearing for cell shape; muscle contraction; cell shape movements; cleavage furrow; muscle contraction

Question 22

intermediate filaments

Answer 22

cables of keratin; tension bearing; anchorage of nucleus and other organelles; nuclear lamina

Question 23

eukaryotic flagella

Answer 23

9 outer doublets of microtubules and 2 single inner microtubules with dynein arms to provide the motor movement

Question 24

basal body

Answer 24

attaches flagella to cell body and has 9 outer triplets of microtubules with no inner microtubules

Question 25

collagen

Answer 25

part of ECM; fibers that are embedded in dense proteoglycan complex

Question 26

fibronectin

Answer 26

attaches the ECM to integrins embedded in plasma membrane

Question 27

plasmodesmata

Answer 27

water and small solutes pass between the cell wall of plants

Question 28

tight junctions

Answer 28

form a seal around the cells preventing leakage of fluid across cell layers

Question 29

desmosomes

Answer 29

fasten cells together strongly; attached to intermediate filaments in the cytoplasm

Question 30

gap junctions

Answer 30

passage of water, ions, sugars, amino acids and other small molecules between cells

Question 31

Low temp membrane

Answer 31

Unsaturated hydrocarbons and cholesterol block phospholipids from packing too closely together at low temps

Question 32

Integral proteins

Answer 32

Penetrate the hydrophobic core of lipid bilayer; only transmembrane proteins span membranes

Question 33

Peripheral proteins

Answer 33

Proteins loosely bound to membrane surface; often to integral proteins

Question 34

Channel proteins

Answer 34

Have hydrophilic channel that allows molecules to use as a tunnel

Question 35

Aquaporins

Answer 35

Passage of water molecules through specific channel protein

Question 36

Carrier proteins

Answer 36

Hold onto molecules and change shape that allows molecules to pass through

Question 37

Osmosis

Answer 37

Water moves from area of higher water concentration to lower water concentration

Question 38

Tonicity

Answer 38

The ability of a solution to cause a cell to gain or lose water

Question 39

Hypertonic

Answer 39

More nonpenetrating salutes outside; cell will lose water and die

Question 40

Hypotonic solution

Answer 40

Water enters the cell faster than it leaves and will swell

Question 41

Plasmolysis

Answer 41

Plant cell in hypertonic solution; cell will lose water and wilt

Question 42

Turgid

Answer 42

Normal environment for plant is hypotonic solution because of plant wall

Question 43

Active transport

Answer 43

Carrier proteins that expend energy to pump molecules against its gradient

Question 44

Electrochemical gradient

Answer 44

Cytoplasm of a cell is negative in charge compared to extracellular fluid; inside is more negative than outside

Question 45

Electrogenic pump

Answer 45

Transport protein that generates voltage across a membrane

Question 46

Cotransport

Answer 46

Can couple downhill diffusion to uphill transport of second substance against concentration gradient

Question 47

Endocytosis

Answer 47

Phagocytosis, pinocytosis, receptor mediated endocytosis

Question 48

Receptor mediated endocytosis

Answer 48

Ligands of potentially low concentration binds to receptors in coated pits