A2.2 - Cell Structure

Question 1

cell theory

Answer 1

all living things are made of one or more cells

Question 2

magnification triangle formulas

Answer 2

I = A x M
A = I/M
M = I/A

Question 3

characteristics of light microscopes

Answer 3

low magnification & resolution (20,000x)
inexpensive
easy specimen preperation
specimen can be living

Question 4

characteristics of electron microscopes

Answer 4

greater magnification & resolution (500,000x)
expensive
lengthy specimen preperation
black and white (unless using fluorescent stain)
kills cells

Question 5

fluorescent stains

Answer 5

absorb then re-emit light at different wavelengths (brightnening)

Question 6

immunofluorescence

Answer 6

uses antibodies to bind to different structures

Question 7

how does immunofluorescent stains work

Answer 7

different fluorescent stains bind to different antibodies to create different colored images

Question 8

process of freeze fracture electron microscopy

Answer 8

rapidly freeze a sample
steel blade fractures sample at weakest point
ice is removed
platinum vapor attaches to create replica of surface
only viewed in electron microscope
helpful for understanding membrane 3D structure

Question 9

Cryogenic Electron Microscopy (Cryo - EM)

Answer 9

freezes layer of protein
viewed on electron microscope
computer looks for pattern
can see individual atoms
allows for understanding of protein structure

Question 10

how many micrometers is 1 mm

Answer 10

1000 micrometers

Question 11

structures common to all living organisms

Answer 11

DNA
Cytoplasm
Cell Membrane

Question 12

DNA

Answer 12

stores genetic information to code for proteins

Question 13

Cytoplasm

Answer 13

water based solution where metabolic reactions occur (ex: respiration)

Question 14

Plasma Membrane

Answer 14

semi permeable phospholipid bilayer

Question 14

characteristics of prokaryotic cells

Answer 14

simple, small,
lack nucleus
non-compartmentalized
have cell wall
naked DNA (no histones)
70’s ribosomes

Question 15

characteristics of eukaryotic cells

Answer 15

larger than prokaryotes
have cell wall
compartmentalized
80’s ribosomes
have nucleus & mitochondria

Question 16

processes of life (MR.SHENG)

Answer 16

metabolism
reproduction
stimuli response
homeostasis
excretion
nutrition
growth

Question 17

metabolism def

Answer 17

sum of all enzyme catalyzed reaction in a cell

Question 18

reproduction def

Answer 18

production of offspring

Question 19

stimuli response def

Answer 19

internal & external reactions

Question 20

homeostasis def

Answer 20

maintenance of stable internal environment

Question 21

excretion def

Answer 21

removal of excess waste

Question 22

nutrition def

Answer 22

getting nutrients required for growth & maintenance

Question 23

growth def

Answer 23

increasing in size & number of cells

Question 24

examples of unicellular organisms

Answer 24

paramecium chlamydamonas

Question 25

components of paramecium

Answer 25

cilia contractile vacuole nucleus food vacuole cytoplasm

Question 26

components of chalmydamonas

Answer 26

flagella nucleus contractile vacuole chloroplast eye spot

Question 27

features exclusive to animal cells

Answer 27

centrioles undulipodia (cilia, flagellum)

Question 28

features exclusive to plant cells

Answer 28

plastids (choloroplast) cell wall vacuoles

Question 29

exceptions to cell theory

Answer 29

RBC - no nucleus or DNA phloem sieve tubes - nucleus & organlles break down, rely on companion cells skeletal muscle - multi-nucleiated aseptate fungal hypahe: walls that separate cells are absent (aseptated: not separate)

Question 30

distinguishing features of prokaryotes in microscopy (shape, size & features)

Answer 30

rod or round, spiral shape smaller than 10 micrometers no membrane bound organelles

Question 31

distinguishing features plant cells in microscopy

Answer 31

geometric/rigid shape due to cell wall look for chloroplast & central vacuole

Question 32

distinguishing features of animal cells in microscopy

Answer 32

no central vacuole no chloroplast

Question 33

organelles found in eukaryotes (13)

Answer 33

nucleus rough ER, smooth ER golgi apparatus lysosome (animals) mitochondira free ribosomes chloroplast (plant) vacuole & vesicle microtubules centrioles cytoskeleton cilia & flagella

Question 34

nucleus

Answer 34

double membrane holds chromosomes DNA w/ histones makes ribosomes

Question 35

Rough endoplasmic reticulum

Answer 35

flat cisternae w/ ribosomes synthesis of proteins uses vesicles to pass proteins to golgi

Question 36

smooth endoplasmic reticulum

Answer 36

branched membranes synthesizes lipids (smooth = oily)

Question 37

golgi apparatus

Answer 37

flat, curved cisternae processes proteins from rER

Question 38

lysosomes

Answer 38

sphere containing enzymes for digestion (lipase) darkly stained in micrograph

Question 39

mitochondria

Answer 39

site of aerobic respiration (Krebs) couble membrane inner membran contains cristae

Question 40

free ribosomes

Answer 40

small, dark structure no membrane synthesizes proteins (rRNA)

Question 41

chloroplast

Answer 41

double membrane stacks of thylakoid discs photosynthesis

Question 42

vacuoles

Answer 42

store water (central vacuole) large in plants small in animals used by unicellulars to get rid of excess water (homeostasis)

Question 43

vesicles

Answer 43

very small vacuole used for transport proteins= rER --> Golgi

Question 44

microtubules

Answer 44

small cylindrical fibers move chromosomes in cell division

Question 45

centrioles

Answer 45

found in animal cells anchor point for microtubules

Question 46

cytoskeleton

Answer 46

protein fibers easily break down & reform maintenance of shape moves parts around cells

Question 47

cilia & flagella

Answer 47

made of microtubules used for movement flagella = longer & fewer cilia = shorter & many