Exam 2 Flashcards
1
Q
resolving power
A
ability of the microscope to show two objects as separate
2
Q
light micrographs for…
A
viewing living cells
3
Q
Used to explore structures & functions of cells
A
electron microscope
4
Q
electron microscope can magnify x______ and distinguish between objects ___ nm apart
A
100,000
0.2
5
Q
examines cell surfaces
A
scanning electron microscope
6
Q
examines inside of cells
A
transmission electron microscope
7
Q
cell theory
A
all living things are made of cells & all cells come from other cells
8
Q
first described cells
A
Robert Hooke
9
Q
prokaryotic organisms
A
bacteria & archaea
10
Q
prokaryotes appeared ____ million yrs ago
A
3.5
11
Q
contains DNA in prokaryote
A
nucleoid
12
Q
sticky coating over prokaryote
A
capsule
13
Q
eukaryotes appeared ___ million yrs ago
A
2.1
14
Q
3 features common to prokaryotes & eukaryotes
A
plasma membrane
DNA
ribosomes
15
Q
composition of ribosome
A
protein & rRNA
16
Q
system of organelles connected to nuclear envelope
A
endomembrane system
17
Q
components of endomembrane system
A
ER
Golgi
lysosomes
vesicles
vacuoles
18
Q
function of RER
A
produce membrane proteins & secretory proteins - packages proteins into transport vesicles
19
Q
function of SER
A
produces lipids, including steroids - metabolizes carbs - helps liver detox circulating drugs
20
Q
function of Golgi
A
receives, refines, stores, sorts & distributes chemical products - uses transport vesicles to package products
21
Q
function of lysosomes
A
sac of digestive hydrolytic enzymes - break down proteins, polysaccharides, fats, nucleic acids - involved in food digestion & recycling
22
Q
function of contractile vacuole
A
pump out water to maintain osmotic pressure - found in protists
23
Q
function of central vacuole
A
store nutrients, absorb water, may contain pigments or poisons, and help maintain cell shape - found in plants
24
Q
thick substance inside mitochondria
A
matrix
25
thick fluid within chloroplasts
stroma
26
drums made of thylakoids
grana
27
hollow discs containing pigments
thylakoids
28
responsible for similarities between mitochondria & chloroplasts
endosymbiosis
29
function of cytoskeleton
(1) Provides mechanical support, (2) maintains cell shape & (3) provides movement for the cell & its molecules/organelles
30
microfilaments
thin & solid - aid in muscle movement (actin & myosin)
31
intermediate filaments
structural support, hold organelles in place
32
microtubules
straight & hollow - guide movement of cells, cilia, flagella & chromosomes during division
33
cell wall composed mainly of…
cellulose
34
function of middle lamella
holds neighboring cells together because it is continuous with cell walls
35
middle lamella includes…
pectin
36
4 components of cell membrane
* Phospholipid bilayer
* Proteins
* Cholesterol
* Carbohydrates
37
turgid state
plants require hypotonic environment
38
3 steps of cell signalling
reception, transduction, response
39
cell respiration equation
**C6H12O6 + 6O2** **→** **6CO2 + 6H2O + ATP + heat**
40
substance loses electrons
oxidation
41
substance gains electrons
reduction
42
electron donor
reducing agent
43
electron acceptor
oxidizing agent
44
during cell respiration, glucose is _______ and O2 is \_\_\_\_\_\_\_
oxidized
reduced
45
**STEPS OF GLYCOLYSIS**
* _Energy investment phase_
* 1 ATP used to produce glucose 6-phosphate
* Fructose-6 phosphate created
* 1 ATP used to create 1,6-biphosphate
* molecule split into G3P or DHAP
* _Energy payoff phase_
* G3P & DHAP converted to 1,3-biphosphoglycerate (2 NADH produced)
* phosphates taken from each molecule to phosphorylate 2 ADP
* Water loss phase — 2 more ADP phosphorylated & 2 pyruvates formed
46
net gain of glycolysis
2 ATP
2 NADH
47
**STEPS OF PYRUVATE OXIDATION**
* pyruvates converted to acetyl coenzyme A
* release of CO2
* produces 2 NADH & 2 H+
48
overall steps of cell respiration
1. glycolysis
2. pyruvate oxidation
3. citric acid cycle
4. oxidative phosphorylation & chemiosmosis
49
gain of pyruvate oxidation
2 acetyl CoA
2 NADH
2 H+
50
there are ___ total steps of citric acid cycle
8
51
there are __ cycle of the citric acid cycle per glucose
2
52
**STEPS OF CITRIC ACID CYCLE**
| (boiled down)
* acetyl group joins oxaloacetate, forming citrate
* next 7 steps decompose citrate back to oxaloacetate
53
gain of citric acid cycle (both turns)
2 ATP
6 NADH
2 FADH2
54
NADH drops electrons into _______ and FADH2 into \_\_\_\_\_\_\_
complex 1
complex 2
55
proteins electrons are transferred through
cytochromes
56
each cytochrome has an…
iron atom
57
electrons pulled down ETC in cell respiration by…
O2
58
energy released from ETC in cell respiration is used…
to push H+ from the mitochondrial matrix to the intermembrane space
59
once the proton gradient is produced in the mitochondria, they diffuse…
through ATP synthase into mitochondrial matrix
60
work produced by H+ gradient
proton motive force
61
gains of chemiosmosis
26-28 ATP
62
energy flow in cellular respiration
glucose → NADH → ETC → proton motive force → ATP
63
\_\_% of energy in a glucose is transferred to ATP; the rest is lost as heat
34
64
\_\_\_\_\_ ATP made per 1 glucose
30-32
65
how does anaerobic respiration work?
uses another electron acceptor at ETC besides O2
66
how does fermentation work?
uses substrate-level phosphorylation
67
fermentation consists of…
glycolysis plus reactions that regenerate NAD, which can be reused by glycolysis
68
fermentation produces ___ ATP per glucose
2
69
2 common types of fermentation
alcohol
lactic acid
70
in alcohol fermentation, pyruvate is converted to..
ethanol
71
which fermentation releases CO2, and which does not?
alcohol does
lactic acid does not
72
in lactic acid fermentation, pyruvate becomes…
NAD & lactate
73
use fermentation or anaerobic respiration - cannot survive in O2
obligate anaerobes
74
can use fermentation or aerobic cellular respiration
facultative anaerobes
75
producers - survive on inorganic molecules & produce organic ones
autotrophs
76
use sunlight to make organic molecules
photoautotrophs
77
consumers - use organic material
heterotrophs
78
major location of chloroplasts
mesophyll cells in leaves
79
each mesophyll contains ____ chloroplasts
30-40
80
pores in leaves allowing gas exchange
stomata
81
photosynthesis equation
6CO2 + 12 H2O + light → C6H12O6 + 6 O2 + 6 H2O
82
2 stages of photosynthesis
light reactions
Calvin cycle
83
ATP generated in plants by \_\_\_\_\_\_\_\_\_\_
photophosphorylation
84
other terms for light
electromagnetic energy or electromagnetic radiation
85
wavelength
distance between crests of light waves
86
entire range of radiation (light)
electromagnetic spectrum
87
visible light wavelengths
380-750nm
88
“particles” of light
photons
89
absorb visible light
pigments
90
best light for photosynthesis
blue-violet and some red
91
key light-capturing pigment
chlorophyll-a
92
accessory pigments
chlorophyll-b
carotenoids
93
measures pigment’s ability to absorb various wavelengths
spectrophotometer
94
graph plotting pigment’s light absorption
absorption spectrum
95
action spectrum of photosynthesis first demonstrated by….
how?
Theodor W. Engelmann
Exposed different segments of algae to different wavelengths & measured O2 produced via the growth of aerobic bacteria
96
photosystems consist of…
reaction center complex surrounded by light-harvesting complexes
97
reaction center complex
association of proteins holding a pair of chlorophyll-a molecules & a primary electron acceptor
98
light harvesting complex
pigment molecules bound to proteins
99
reaction-center pigment in PSII
chlorophyll P680
100
reaction-center pigment in PSI
chlorophyll P700
101
2 possible routes for electron flow in light reactions
linear
cyclic
102
**STEPS FOR LINEAR ELECTRON FLOW IN LIGHT REACTIONS**
* **photon hits pigment in PSII**
* P680 excited
* electrons passed to electron acceptor, making P680+
* H2O is split to replace electrons—H+ and O2 are released into thylakoid space
* electrons fall down ETC
* energy drives pumping of protons into thylakoid space across thylakoid membrane
* protons diffuse through ATP synthase, producing ATP
* **photon hits pigment in PSI**
* P700 excited
* electrons fall down ETC & are accepted by ferredoxin
* NADP+ reductase reduces NADP to form NADPH
103
how is cyclic electron flow different from linear?
electrons cycle back from ferredoxin to the PSI reaction center via plastocyanin
bypasses PSII entirely
produces ATP, but no NADPH or O2
prevents light-induced damage from O2
104
gains from linear light reactions
ATP
NADPH
105
location of Calvin cycle
stroma
106
calvin cycle turns…
3 times
107
during Calvin cycle, CO2 becomes…
glyceraldehyde 3-phosphate (G3P)
108
**STEPS FOR CALVIN CYCLE**
* _carbon fixation_
* input 3 CO2
* CO2 is fixed to RuBP by rubisco, forming 6 3-phosphoglycerates
* 6 ATP added, 6 electrons from NADPH added, 6 phosphates lost
* _reduction_
* 6 3-phosphoglycerate molecules are reduced by NADPH & ATP to form 6 _G3P_ molecules
* 1 G3P molecule exits cycle to form a sugar
* _regeneration_
* remaining 5 G3P molecules (15 carbons) are reused to form RuBP
* ADP & NADP+ are returned back to light reactions
109
\_\_\_\_ G3P required to form glucose
2
110
hot, dry conditions favor…
photorespiration
111
most plants are ___ plants
\_\_\_ plants use photorespiration
\_\_\_\_\_ plants separate photosynthesis temporally
C3
C4
CAM
112
how is photorespiration different?
* rubisco adds O2 instead of CO2 in Calvin cycle, producing a 2-carbon compound
* Consumes O2 & large amounts of energy
* releases CO2
* does not produce ATP or sugar
113
why is photorespiration a problem?
can drain 50% of carbon fixed by Calvin cycle
114
what is C4 plants' advantage
minimize cost of photorespiration by incorporating CO2 into 4-C molecules instead of 3-C molecules
115
2 types of cells in C4 plants' leaves
* _Bundle-sheath cells_ - arranged in tightly packed sheaths around veins of a leaf
* _Mesophyll cells_ - loosely packed between bundle sheath and leaf surface
116
C4 plants' process for producing sugar
* Production of 4-C molecules catalyzed by PEP carboxylase in mesophyll cells
* 4-C compounds moved into bundle sheath cells
* Calvin cycle occurs in bundle sheath cells
* CO2 is released throughout the day slowly
117
CAM stands for…
crassulacean acid metabolism
118
how do CAM plants work?
* separates time between intermediate and entry into Calvin - organic acids are released into Calvin cycle during the day
* Stomata is open only at night - closed during the day to prevent water loss
* Organic acids are stored in vacuoles
119
examples of CAM plants
succs
pineapples
