Chapter 6

Question 1

Biologists use ___ and ___ to study ___

Answer 1

microscopes, biochemistry, cells

Question 2

Cell walls were first seen by

Answer 2

Robert Hooke

Question 3

Who first saw living cells?

Answer 3

Antoni van Leeuwehoek

Question 4

light microscope (LM)

Answer 4

visible light passed through specimen and glass lenses; lenses refract light to magnify image

Question 5

3 parameters for microscope

Answer 5

magnification, resolution, contrast

Question 6

magnification

Answer 6

ratio of object’s image size to real size

Question 7

resolution

Answer 7

clarity of image; min distance 2 points can be separated and still be distinguished as separate points

Question 8

contrast

Answer 8

difference in brightness between light/dark areas

Question 9

organelles

Answer 9

membrane-enclosed structures within eukaryotic cells

Question 10

electron microscope (EM)

Answer 10

focuses beam of electrons through specimen/onto surface

resolution is inversely related to wavelength of light/electrons

Question 11

scanning electron microscope (SEM)

Answer 11

detailed study of topography of specimen
electron beam scans surface of sample, which excites electrons on the surface and they’re detected by a device that translates the pattern of electrons into an electronic signal

Question 12

types of LM

Answer 12

brightfield (stained/unstained), phase contrast, differential-interference-contrast (nomarski), fluorescence, confocal, deconvolution, super-resolution

Question 13

types of EM

Answer 13

SEM and TEM

Question 14

transmission electron microscope (TEM)

Answer 14

study internal structure of cells
aims electron beam through very thin section of specimen
use electromagnets as lenses to bend paths of electrons

Question 15

cytology

Answer 15

study of cell structure

Question 16

biochemistry

Answer 16

study of chemical processes (metabolism) of cells

Question 17

cell fractionation

Answer 17

technique for taking cells apart and separating major organelles and sub cellular structures from one another
uses centrifuge which spins around test tubs w/ mixtures of disrupted cells at series of increasing speeds
resulting force causes subset to settle to the bottom of tube
enables bulk of a specific cell component

Question 18

___ cells have internal membranes and ___ their functions

Answer 18

eukaryotic, compartmentalize

Question 19

cytosol

Answer 19

semifluid, jellylike substance, in all cells, subcell components suspended in

Question 20

chromosomes

Answer 20

carry genes in DNA form

Question 21

ribosomes

Answer 21

make proteins according to gene instructions

Question 22

eukaryotic cell

Answer 22

DNA in nucleus, bound by double membrane

Question 23

prokaryotic cell

Answer 23

DNA concentrated in region not membrane enclosed (nucleoid)

Question 24

cytoplasm

Answer 24

region between nucleus and plasma membrane

interior of either type of cell

Question 25

which is larger: eukaryotic/prokaryotic?

Answer 25

eukaryotic

Question 26

plasma membrane

Answer 26

selective barrier for passage of O2, nutrients, wastes; encloses cell

Question 27

larger organisms don't have larger cells

Answer 27

just have more cells

Question 28

microvilli

Answer 28

long, thin projections that increase SA w/o increase in volume

Question 29

flagellum

Answer 29

motility structure present in some animal cells | comprised of cluster of microtubules within an extension of plasma membrane

Question 30

centrosome

Answer 30

region where cell's microtubules are initiated | contains pair of centrioles

Question 31

cytoskeleton

Answer 31

reinforces cell's shape; functions in cell movement; component are made of protein; includes microfilaments, intermediate filaments, microtubules

Question 32

peroxisome

Answer 32

organelle w/ various specialized metabolic functions; produces hydrogen peroxide as by product, then converts to water

Question 33

mitochondrion

Answer 33

organelle where cell respiration occurs and most ATP is generated

Question 34

endoplasmic reticulum (RER/SER)

Answer 34

network of membranous sacs and tubs; active in membrane synthesis and synthetic/metabolic processes has rough and smooth regions

Question 35

nuclear envelope

Answer 35

double membrane enclosing nucleus, perforated by pores, continuous w/ ER nucleus

Question 36

nucleolus

Answer 36

nonmembrane structure involved in production of ribosomes; nucleus has 1+ nucleoli nucleus

Question 37

chromatin

Answer 37

material consisting of DNA and proteins; visible in dividing cell as individual condensed chromosomes nucleus

Question 38

ribosomes

Answer 38

complexes that make proteins; free in cytosol/bound to RER/nuclear envelope

Question 39

Golgi apparatus

Answer 39

organelle active in synthesis, modification, sorting, secretion of cell produts

Question 40

lysosome

Answer 40

digestive organelle where macromolecules are hydrolyzed

Question 41

central vacuole

Answer 41

prominent organelle in older plant cells; storage, breakdown of waste products, hydrolysis of macromolecules

Question 42

choloroplast

Answer 42

photosynthetic organelle; converts energy of sunlight to chemical energy stored in sugar molecules

Question 43

plasmodesmata

Answer 43

cytoplasmic channels through cell walls that connect the cytoplasms of adjacent cells

Question 44

cell wall

Answer 44

outer layer that maintains cell's shape and protects cell fr mechanical damage; made of cellulose, other polysaccharides, protein

Question 45

____ cell's genetic instructions are housed in the ___ and carried out by the ___

Answer 45

eukaryotic, nucleus, ribosomes

Question 46

nucleus

Answer 46

contains most of genes in eukaryotic cells; most conspicuous organelle

Question 47

nuclear envelope

Answer 47

encloses nucleus; double membrane w/ phosopholipid bilayer

Question 48

nuclear lamina

Answer 48

netlike array of protein filaments that maintain shape of nucleus by mechanically supporting the nuclear envelope; lines nuclear side of envelope

Question 49

chromosomes

Answer 49

carry genetic info; contains 1 long DNA molecule associated w/ many proteins

Question 50

chromatin

Answer 50

DNA and proteins making up chromosomes