CH6: TOUR OF THE CELL

Question 1

visible light is passed through a specimen and then through glass lenses

lenses refract (bend) the light so that the image is magnified and focused on an eye lens

Answer 1

Light Microscope

Question 2

the measure of the clarity of the image or the minimum distance of two distinguishable points

Answer 2

resolution

Question 3

visible difference in brightness between parts of the sample and the background

Answer 3

contrast

Question 4

an image is formed by transmitting light through cell (white bg)

Answer 4

bright-field microscopy

Question 5

rays of light are directed from the side; only light scattered by the specimen enters the lenses

Answer 5

dark-field microscopy

Question 6

variations in density cause difference int he way various regions of the cytoplasm refract light

Answer 6

Phase Contrast Microscopy
Differential Interference-Contrast Microscop

Question 7

filters transmit light that emitted by by fluorescently stains that bind specifically to DNA or specific protein molecules

Answer 7

fluorescence microscope

Question 8

produces a sharper image than standard fluorescence microscopy
a computerized microscope produces optical sections that are assembled into a 3D image

Answer 8

confocal microscopy

Question 9

allows researchers to study fine details (ultrastructure) of cells

some have resolving powers less than 1nm (magnification > 1 million X)

electron beam consists of energized electrons, which can be focused by electromagnets just as images are focused by glass lenses in a light microscope

Answer 9

Electron Microscope

Question 10

• specimen embedded in plastic and thinly sectioned
• the electron beam passes through the specimen and falls onto a photographic plate or fluorescent screen
• focus beam of electrons through specimen
• internal structure of cells

Answer 10

Transmission Electron Microscope (TEM)

Question 11

• the specimen is coated with gold or some other metal
• emission patterns of secondary electrons give a 3D picture of the surface
• focuses a beam of electrons onto the surface of a specimen, providing images that look 3D

Answer 11

Scanning Electron Microscope (SEM)

Question 12

takes cells apart and separates the major organelles from one another

fractionate cells into component parts and allows scientists to determine the functions of organelles

Answer 12

Cell Fractionation

Question 13

Domains of Prokaryotic Cells

Answer 13

Bacteria and Archaea

Question 14

Kingdoms of Eukaryotic Cells

Answer 14

protists, fungi, animals, plants

Question 15

Basic features of ALL cells

Answer 15

• plasma membrane
• cytosol (semifluid substance)
• chromosomes (carry gens)
• ribosomes (make proteins

Question 16

characteristics of prokaryotic cells

Answer 16

• no nucleus
• no membrane-bound organelles

Question 17

DNA in an unbound region in prokaryotic cells

Answer 17

nucleoid

Question 18

lines nuclear side of envelope (inner side) and is made of proteins and maintains the shape of the nucleus

Answer 18

nuclear lamina

Question 19

site of ribosomal RNA (rRNA) synthesis

Answer 19

nucleolus

Question 20

what makes up the endomembrane system?

Answer 20

Nuclear envelope
ER
Golgi apparatus
Lysosomes
Vacuoles
Plasma membrane

Question 21

small, membrane-bound sacs that play a role in transport, storage, or secretion

Answer 21

vesicles

Question 22

what are the functions of smooth ER

Answer 22

synthesizes lipids
metabolizes carbs
detoxifies drugs/poisons
stores calcium ions

Question 23

proteins covalently bonded to carbs; secreted by rough ER ribosomes

Answer 23

glycoproteins

Question 24

membranous sac of digestive enzymes;
fuses with food vacuole and digests the molecules

Answer 24

lysosome

Question 25

certain cells can engulf another cell (i.e. macrophage engulf foreign invader and breaks it down)

Answer 25

phagocytosis

Question 26

the process where a lysosome uses enzymes to recycle the cell's own organelles and macromolecules

Answer 26

autophagy

Question 27

large vesicles with many purposes from ER and golgi

Answer 27

vacuole

Question 28

large vesicle formed by phagocytosis

Answer 28

food vacuoles

Question 29

large vesicle found in many freshwater protists that pump excess water out of cells

Answer 29

contractile vacuoles

Question 30

large vesicles found in many mature plant cells that hold organic compounds and water

Answer 30

central vacuoles

Question 31

part of golgi where vesicles enter

Answer 31

cis Golgi

Question 32

golgi closest to plasma membrane

Answer 32

trans golgi

Question 33

cellular respiration to ATP

Answer 33

mitochondria

Question 34

photosynthesis from sunlight

Answer 34

chloroplasts

Question 35

oxidative organelles; specialized metabolic compartments; make hydrogen peroxide (H2O2) and turn it to water

Answer 35

peroxisomes

Question 36

mitochondria and chloroplasts share similarities with WHAT (double membrane, free ribosomes, circular DNA molecules, grow and reproduce independently)

Answer 36

bacteria

Question 37

theory that early eukaryotes engulfed an oxygen using nonphotosynthetic prokaryotic cell and formed a relationship with the host cell endosymbionts - mitochondria photosynthetic prokaryote - chloroplast

Answer 37

endosymbiont theory

Question 38

mitochondria smooth outer membrane and inner membrane folded into ________

Answer 38

cristae

Question 39

the innermost compartment within a mitochondrion, enclosed by the inner membrane

Answer 39

mitochondrial matrix

Question 40

green pigment in chloroplasts

Answer 40

chlorophyll

Question 41

double-membrane organelles which are found in the cells of plants and algae, like chloroplast

Answer 41

plastids

Question 42

roles of cytoskeleton

Answer 42

- support cell and maintain shape - interacts with motor proteins to produce motility (ability to move) - vesicles can walk on cytoskeleton

Question 43

- thickest cytoskeleton (25nm) - hollow tubes - make of tubulin (aka tubulin polymers) - shaping cell - guide movement of organelles separate chromosomes in cell division

Answer 43

microtubules

Question 44

- thinnest cytoskeleton (7nm) - two intertwined (wrapped around each other) strands of actin - made of actin (aka actin filaments) - maintain cell shape - muscle contraction - cell motility - division in animal cells - make up microvilli

Answer 44

microfilaments

Question 45

- 8-12 nm - fibrous proteins coiled into cables - types of proteins (e.g. keratin) - maintain cell shape, anchor nucleus and certain organelles - forms nuclear lamina - more PERMANENT that other structures

Answer 45

intermediate filaments

Question 46

two ______ make 1 _____ which has ____ triplets of microtubules in a ring

Answer 46

centrioles, centrosome, 9

Question 47

motor protein that drives bending movements of cillium or flagellum its arms grab, move, release the outer microtubules

Answer 47

dynein

Question 48

microfilaments form this 3D network inside the plasma membrane to support cell shape

Answer 48

cortex

Question 49

cellular extensions that help cells crawl along a surface

Answer 49

pseudopodia

Question 50

circular flow of cytoplasm within cells

Answer 50

cytoplasmic streaming

Question 51

what cells can have cell walls

Answer 51

prokaryotes, fungi, and some unicellular eukaryotes (plants)

Question 52

functions of plant cell wall

Answer 52

- protect plant cell - maintain shape - prevent burst in excess uptake of water

Question 53

thin layer between primary cell wall and adjacent cells/secondary cell wall (in some cells, inner wall of plasmodesmata)

Answer 53

middle lamella

Question 54

channels between adjacent plant cells (like desmosomes for plants) small solutes and water can pass

Answer 54

plasmodesmata

Question 55

made up of glycoproteins (collagen, proteoglycans, fibronectin) that bind to receptor proteins in membrane - regulate cell behavior by communication through integrins - influence gene activity in nucleus - mechanical signaling through cytoskeleton changes that trigger chemical signals in cell

Answer 55

Extracellular Matrix

Question 56

receptor proteins in membrane

Answer 56

integrins

Question 57

neighboring cells adhere, interact, or communicate through direct physical contact

Answer 57

cell junctions

Question 58

prevent leakage of extracellular fluid; mostly epithelial cells like intestine lining

Answer 58

tight junctions

Question 59

anchor cells together button-like; made of keratin

Answer 59

desmosomes

Question 60

provide cytoplasmic channels between adjacent cells (allows water and small molecules to pass)

Answer 60

gap junctions