Ch 2 Cells

Question 1

Cell Theory

Answer 1

1. All living things are composed of cells
2. cells are the basic unit of all organisms
3. all cells arise from preexisting cells

Question 2

prokaryotes

Answer 2

have no nucleus or other internal membranes

Question 3

eukaryotes

Answer 3

have nucleus and are more complex. make up every other form of life except bacteria.

Question 4

which cells have membrane bound organelles

Answer 4

eukaryotes

Question 5

which cells have a single, circular chromosome.

Answer 5

prokaryote

Question 6

which cells have plasmids

Answer 6

prokaryote

Question 7

which cells have smaller ribosomes

Answer 7

prokaryotes

Question 8

which cells have larger ribosomes

Answer 8

eukaryotes

Question 9

which cells have cytoskeletal elements, like microfilaments

Answer 9

eukaryotes

Question 10

which cells have sizes of 1-10 um

Answer 10

prokaryotes

Question 11

which cells have tough external cells walls

Answer 11

prokaryotes and eukaryotic plant.protist cells

Question 12

how old is the earth

Answer 12

4.6 billion years old

Question 13

theory of endosymbiosis

Answer 13

eukaryotic cells containing organelles like mitochondria and chloroplasts evolved whne free-living prokaryotes took up permanent residence inside other prokaryotic cells. This was the origin of a eukaryotic cell.

Question 14

chromatin network

Answer 14

a network of DNA wrapped with histones into chromosomes

Question 15

nucleolus

Answer 15

prominent region inside nucleus of a cell that is not dividing. compnonents of ribosomes are synthesized here.

Question 16

ribosomes

Answer 16

site of protein synthesis, made of ribosomal RNA and protein. suspended in cytoplasm or bound to ER

Question 17

Endoplasmic reticulum

Answer 17

system of membrane channels that traverse cytoplasm.

Question 18

Rough ER

Answer 18

studded with ribosomes. site of protein synthesis AS WELL AS cytoplasmic transport.

Question 19

Smooth ER

Answer 19

Synthesizes steroid hormones. Connects ER to Golgi. detoxifies cell.

Question 20

Golgi Apparatus

Answer 20

contains flattened sacs of membranes stacked next to each other and surrounded by vesicles. They modify, store, and package substances produced in the rough ER. also secretes substances to other pats of cell and to cell surface.

Question 21

lysosome

Answer 21

sac of hydrolytic (digestive) enzymes enclosed by single membrane. principle site of intracellular digestion. breaks down and recycles cell parts, renews cells. aids in apoptosis.

Question 22

mitochondrion

Answer 22

site of cell respiration. consist of outer double membrane and folded inner membranes called criste.

Question 23

vacuole

Answer 23

store substances for cell.

Question 24

vesicle

Answer 24

tiny vacuole.

Question 25

plastids

Answer 25

only found in algae and plants. 3 types: chloroplasts, leucoplasts, and chromoplasts,

Question 26

chloroplasts

Answer 26

green, contain chlorophyll, sites of photosynthesis. inner membrane of grana which lie in the stroma.

Question 27

leucoplasts

Answer 27

plastids that are colorless and store starch.found in roots or tubers.

Question 28

chromoplasts

Answer 28

plastids that store carotenoid pigments and are responsible for colors of carrots, tomoatoes, and daffodils.

Question 29

cytoskeleton

Answer 29

network of protein filaments that extends throughout the cytoplasm and gives the cell its shape.

Question 30

microtubules

Answer 30

thick hollow tubes that make up cilia, flagella, and spindle fibers.

Question 31

microfilaments

Answer 31

made of protein actin and help support the shape of the cell.

Question 32

centrioles and centrosomes

Answer 32

only found in animal cells. two centrioles are a right angles to each other and make up one centrosome. made up of microtubules arranged in circle

Question 33

cilia and flagella

Answer 33

made of microtubules, cilia shorter than flagella

Question 34

Cytosol

Answer 34

refers to the semiliquid portion of the cytoplasm

Question 35

cyclosis

Answer 35

process where organelles suspended in the cytosol and get carried around the cell as cytoplasm cycles around the cell.

Question 36

fluid mosaic

Answer 36

term to describe structure of cell membrane. consists of phospholipid bilayer with molecules of cholesterol embedded within.

Question 37

solvent

Answer 37

the substance that does the dissolving

Question 38

solute

Answer 38

substance being dissolved

Question 39

hypertonic

Answer 39

greater concentration of solute than other solution

Question 40

hypotonic

Answer 40

lower concentration of solute than other solution

Question 41

passive transport

Answer 41

movement of molecules down concentration gradient by diffusion or osmosis. never requires energy

Question 42

simple diffusion

Answer 42

movement of particles from high to low concentrations. this is how alveoli work

Question 43

facilitated diffusion

Answer 43

relies on special protein membrane channels to assist in transporting substances across membrane

Question 44

osmosis

Answer 44

diffusion of water across membrane

Question 45

plasmolysis

Answer 45

cell in hypertonic solution that causes water to leave the cell, causing it to shrink

Question 46

turgid

Answer 46

water enters a plant cell in a hypotonic solution and cell swells. if animal cell, it would burst.

Question 47

active transport

Answer 47

movement of molecules against gradient. requires energy (ATP).

Question 48

exocytosis

Answer 48

active release of molecules from a cell, like synapse of nerve cells.

Question 49

pinocytosis

Answer 49

cell drinking; uptake of large, dissolved molcules.

Question 50

phagocytosis

Answer 50

engulfing of large particles or large organisms by pseudopods.

Question 51

compound microscope

Answer 51

main tool for studying cell structure (cytology)

Question 52

resolution

Answer 52

image clarity

Question 53

phase contrast microscope

Answer 53

light microscope that enhances contrast. useful for living unstained cells

Question 54

transmission electron microscope

Answer 54

useful for study of interior of cells. however, it kills the tissue being studied, elaborate prep, specimens must be thinly sliced, expensive.

Question 55

scanning electron microscope

Answer 55

useful for study of surface of cells. goves 3D appearance. kills tissue

Question 56

ultracentrifuge

Answer 56

enables scientists to isolate components of cells in large quantities by cell fractionation. requires blender

Question 57

freeze fracture

Answer 57

studies details of membrane structure under electron microscope