BIOL Final Exam Content Flashcards
(106 cards)
1
Q
what allows ATP to create energy?
A
hydrolysis
2
Q
Does breaking the phosphate bond
in ATP release energy?
A
NO
3
Q
Let’s simplify. Consider two oxygen
atoms… O + O
Think back to when we talked about covalent
bonds…If left to their own devices, will these atoms:
a) come closer together and bond.
b) go further apart and not bond.
Why?
A
A - they want to share electrons in order to be in a more stable form and fill a valence shell
4
Q
forming a chemical bond ___ energy because atoms are now ____
A
releases; more stable
5
Q
Breaking off phosphate - Going from bonded to
unbonded = ___ stable to ___stable=___
energy to ___ energy.
A
more stable, less stable –> lower, higher
6
Q
Adding bonds from H2O - Going from unbonded to
bonded = ___ stable to ___stable=___
energy to ___ energy.
A
less, more –> higher, lower
7
Q
endergonic reaction
A
energy absorbed by breaking a bond > energy released by forming a bond
8
Q
Which of the following is true regarding the hydrolysis of ATP:
a) Bonds that are broken use more energy than the amount
released by bonds that are forming.
b) Bonds that are broken use less energy than the amount
released by bonds that are forming.
Overall, the hydrolysis of ATP is an exergonic
reaction…it has a net release of energy.
A
B
9
Q
Exergonic reaction
A
energy absorbed by breaking a bond > energy released by forming a bond
10
Q
How to determine what type of reaction it is
A
compare energy absorbed and released
11
Q
Bonded –> Unbonded
A
uses energy
12
Q
Unbonded –> Bonded
A
releases energy
13
Q
Bonding –> unbonding - uses 10 units of energy
unbonding –> bonding - uses 100 units of energy
A
Absorbs 10 units, but releases 100 when broken; net of 90 units released = Exergonic
14
Q
Which type of reaction releases net energy?
A
Exergonic
15
Q
Choose which macromolecule category each of the catalytic molecules
we’ve explored belongs to
a) Lipids
b) Carbohydrates
c) Proteins
d) Nucleic Acids
1. DNA polymerase
2. RNA polymerase
3. Ribosome (*hint: think active site)
4. Spliceosome (splicing and alternative
splicing)
5. RISC (RNAi)
6. ATPase
7. General enzyme
A
Proteins - 1, 2, 6, 7
Nucleic Acid - 3, 4, 5
16
Q
Catalytic Activity
A
molecule that facilitates chemical reactions
17
Q
Activation energy
A
threshold something needs to reach to ensure a bond can be broken
18
Q
____ assist reactants going from bonded to Unbonded, also called the ____
A
enzymes; transition state
19
Q
How do enzymes speed up chemical reactions?
A
Destabilize the bonds in substrates, making reactants Unbonded and lowering activation energy, allowing it to reach the transition state faster
20
Q
what enzyme assists ATP hydrolysis
A
ATPase
21
Q
Gibb’s Free Energy
A
tracks the change in energy over the course of a chemical reactions
22
Q
what form is the energy released from breaking down glucose?
A
high energy electrons
23
Q
catabolic reactions
A
breaking something down - releases energy
23
Q
anabolic reaction
A
building something - using energy
24
goal of cellular respiration
to make ATP
25
T/F ATP can be stored
False
26
where is ATP synthase located
in mitochondrial matrix
27
how does ATP Synthase work?
similar to a water mill, a high concentration of H+ ions in the intermembrance space flows into the matrix and spins the ATP Synthase, providing energy to create ATP
28
1. As the concentration of ATP increases, ATP synthase
will
a) Speed up
b) Slow down
c) Maintain the same rate
2. If the hydrogen ion gradient in the intermembrane
space increases, ATP synthase will
a) Speed up
b) Slow down
c) Maintain the same rate
Matrix
1. B
2. A - greater concentration means heavier flow therefore more activity
29
What builds and maintains the H gradient?
electron transport train - moves ions from the matrix into the space
30
True or false? The molecules of the electron transport chain must
use energy to drive H+ to the intermembrane space and maintain
the high concentration there.
(And what kind of transport is it?)
True - going against the gradient (mitochondrial electrons transport chain - active transport)
31
Glycolysis
1 glucose is broken down into 2 pyruvate molecules - NADH and ATP are released
32
pyruvate processing
1 carbon is removed from each of the pyruvates to make 1 Acetyl CoA. CO2 and NADH are released
33
Krebs Cycle
Acetyl CoA enter the Krebs cycle where both carbons are removed from each - CO2, NADH, FADH2 and ATP are released
34
Oxidative phosphorylation
NADH and FADH2 donate their electrons to the ETC (uses energy to build the H+ gradient)
35
Ultimately, what happens to the
carbons from the original glucose
(6-carbon)?
a) They become carbon dioxide
b) They become ATP
c) They become NADH & FADH2
They become CO2
36
Where does your biomass go when
you lose weight by increasing
energy out over energy in?
a) Urination
b) Defecation
c) Exhalation
d) Perspiration
C - exhalation (CO2)
37
NADH and FADH2 donate ____ to ____
high energy of electrons; molecules of the ETC
38
What happens after N/FADH(2) donates its electrons to the ETC?
a series of redox reactions that pass electrons down the chain
39
Energy is released each time an electron
gets passed from one molecule to the next
in the electron transport chain.
Which molecule, Fe-S (lower) or cyt b (higher) has more
energy (red arrows)?
Cyt-B
40
If a mutation were to diminish the reduction
potential of Cyt-b, which electron carriers
would accumulate in their reduced state?
a) Everything upstream of Cyt-b
b) Cyt-b
c) Everything downstream of Cyt-b
d) A and B
e) B and C
A
41
Within the electron transport chain, which
molecule stores the least energy?
Which molecule is the final electron
acceptor?
Cyt a3
42
What would happen if there was no oxygen
in the cell?
a) Electrons would move faster through the
ETC.
b) Electrons would move slower and back
up in the ETC.
c) Electrons would move through the ETC
at the same rate.
B
43
1. Increasing pyruvate concentration will have what immediate affect
on:
* The rate of the Krebs's cycle?
* The rate of glycolysis?
* The concentration of NADH produced?
2. Slowing the Krebs's cycle will have what immediate affect on:
* The rate of pyruvate processing?
* The concentration of ATP produced?
1. Concentration of NADH produced
2. Concentration of ATP Produced
44
what is the preferred fuel for cellular respiration
carbohydrates
45
if glycogen is low, what can be used as fuel?
stored fat - triglycerides
46
what two components are triglycerides broken into?
glycerol and fatty acids
47
what if ATP, carbs, lipids are low?
proteins can be used in cellular respiration (starvation)
48
Imagine that a mutation prevents the products of glycolysis (pyruvate)
from entering pyruvate processing. How might the cellular respiration
pathway be adjusted to make up for the lack of pyruvate entering
pyruvate processing?
a) Fatty acids from fat entering at Pyruvate.
b) Glycerol from fat entering at Glycolysis.
c) Amino acid (products) entering at Acetyl CoA or the Kreb’s Cycle.
C -
Xa - fatty acids don't enter at pyruvate
Xb - this doesn't fix the problem -
49
What happens to the rest of cellular respiration
during the sprint (O2 and ATP limited)? The athlete’s
levels of NADH are ________ thus the rate or her
Kreb’s cycle and glycolysis will ___________.
a) Increasing, speed up
b) Increasing, slow down
c) Decreasing, speed up
d) Decreasing, slow down
e) Both will stay the same
B - If o2 is low, electron transfer and then stops, ETC stuck in a reduced state so they can't accept any electrons from NADH or FADH2 - eventually everything stops (NADH nowhere to drop electrons)
50
Fermentation regenerates NAD+ so that ...
cell can at least continue to perform glycolysis and produce ATP
51
how does fermentation work?
pyruvate accepts electrons from NADH then converts to lactic acid; bc NAD+ regenerated, glycolysis can continue
52
products of fermentation in yeast cells
alcohol and co2
53
Select all of the following that are
false:
1. Fermentation directly produces ATP.
2. Fermentation allows glycolysis to continue.
3. Fermentation allows cell resp to continue.
1. & 3.
54
Light dependent reaction
Photons + H20 --> ATP + NADPH + O2
55
Calvin Cycle
ATP + NADPH + CO2 --> Carbohydrate
56
Where does photosynthesis happen?
chloroplasts (thylakoid disks in stroma) located in mesophyll cells
57
Photosystems are located ___ in the thylakoid disk membrane. They contain light-absorbing ____ and proteins. ___ is passed from ____ until it reaches the ____
embedded, pigment molecules, light, pigment to pigment, reaction center
58
In these photon transfers, the
receiving molecule
a) Must require less energy for
excitation
b) Must require more energy
for excitation
(compared to the donor
molecule)
A - donating molecule can only donate the amount that it has
59
When a pigment absorbs a photon, the pigment’s electron gets bumped to a higher energy level. An excited pigment is unstable, it
can either transfer energy or its electron to another molecule.
Look back at the diagram: What do (most) excited pigments do in the
photosystems?
a) Transfer electron
b) Transfer energy
B
60
photosystems I
produces ATP
61
62
produces NADH
photosystem II
63
The electron has lost energy, what can P700 do to boost the electron
into a higher energy level?
gets reexcited by another photon (absorb another)
64
The PSII gets electrons from ___________, while the PSI is replenished
by electrons from_________.
water; psII
65
What would immediately happen
if a plant’s cells lacked water?
a) PSI would stop working
b) PSII would stop working
B
66
Electrons are transferred in two different ETCs. These transfers are
energy releasing...just like in cellular respiration.
This is made possible by
a) The H+ gradient in the thylakoid lumen
b) The absorption of light energy by P680 and P700
c) The input of water in PSII
B - this is what boosts the electron to a high enough energy level to keep the transfers happening
67
where does Calvin cycle take place?
stroma
68
Calvin cycle
uses producers to power the fixation of co2 (turning it into a carb)
69
rubisco
binds 6 co2 and 6 RuBP to form PGAL
70
T/F? More energy is
absorbed from breaking
the bonds in CO2 than
is released when the
carbohydrate is formed.
So....
The Calvin Cycle is
a) Endergonic reaction
b) Exergonic reaction
T
A
71
PGAL has 3 carbons. RUBP has 5 carbons. Glucose has 6 carbons.
* Rubisco binds 6 CO2s and 6 RUBP.
* Together they form ____ PGALs.
* So ____ PGALS are needed to make 1 glucose.
* And _____ PGALS totaling ____ carbons get recycled in the Calvin
Cycle to make 6 RUBP.
12, 2,10, 30
72
Put the following in the correct order that
carbon atoms would travel from the
atmosphere into organic molecules in living
organisms and back to the atmosphere:
i. Pyruvate processing
ii. Kreb’s cycle
iii. Pyruvate
iv. Glucose
v. Exhalation
vi. Calvin cycle
vii. Glycolysis
Calvin cycle, glucose, glycolysis, pyruvate, pyruvate processing, Krebs cycle, exhalation
73
how does co2 enter a plant leaf?
stomata
74
When stomata are closed to reduce water loss, what
happens to the relative concentration of CO2: O2
inside the cells?
a) Low CO2 to O2 ratio
b) High CO2 to O2 ratio
A
75
photorespiration
when too much o2 builds up inside the plant - rubisco grabs o2 instead of co2
76
when is photorespiration more likely to occur?
when temps are high - co2:o2 is low, rubisco has greater affinity for o2
77
Photorespiration will not produce a carbohydrate. Look at the Calvin
Cycle, identify which key compound is missing during photorespiration
and answer the question:
Why will photorespiration not produce a carbohydrate?
when rubisco binds to oxygen instead of co2, it is grabbing a molecule without carbon - you need carbon to form a carbohydrate - wasting ATP and not producing glucose
78
what is standard photosynthesis?
C3
79
what are 2 adaptations to prevent photorespiration?
C4 photosynthesis - warm, wet
CAM photosynthesis - warm, dry (prevents water loss)
80
C4 synthesis
separates light dependent reactions from the Calvin Cycle
81
CAM photosynthesis
open stomata at night and co2 is grabbed by PEP carboxylase
82
What are the minimal characteristics that makes something alive?
stored information, reproduction, evolution
83
which macromolecule is the best contender for first life?
RNA
84
chemical evolution
formation of organic molecules from simpler inorganic molecules - occurred in ancient oceans 3.5 billion years ago
85
RNA world
chemical evolution gave rise to an organic molecule, capable to self replicating; RNA
86
Once RNA formed,
how did the first cell arise?
What are the fewest components/characteristics
for a cell to still be considered a cell? Choose 3.
a) Cell membrane
b) Genetic information (DNA or RNA)
c) Ability to replicate
d) Ability to interact with other proto-cells
A,B,C
87
LUCA (last universal common ancestor)
the one type of cell that gave rise to all forms of life (proto cell)
88
A virus is a cell (T/F)
False - it's a particle
89
Components of a virus
nucleic acid contained by a protein shell (capsid and envelop)
90
Capsid
viral protein shell made up of capsomeres - always encoded in the viral genome
91
Viral Envelope
some viruses have lipid membranes - stolen from host cell
92
5 steps of viral infection
1. Attachment to host cell
2. Entry into host cell
3. Replication and gene expression
4. Assembly
5. Release
93
Viral attachment and entry
proteins on the surface of a capsid recognize and stick to certain receptors on a cell surface
- viruses with envelopes fuse their lipids with the cell membrane - or might inject their genetic material into the host cell etc
94
Viral replication and gene expression - viral material is DNA
Genetic material must enter the host to be replicated by host cells' DNA polymerase (if the viral genetic material is DNA) - uses host cell mechanisms to transcribe/translate
95
Viral replication and gene expression - viral material is RNA positive sense
RNA is considered mRNA and translated first - viral proteins (RNA replicase) host cell's ribosomes
96
Viral replication and gene expression - viral material is RNA negative sense
Virus adds its own RNA polymerase to transcribe to mRNA and then the host cell's ribosomes translate it to proteins
97
Assembly and Release
within the host cell, capsid proteins form capsomeres then new viral particles leave the cell (by lysing, budding, etc)
98
Mature red blood cells contain hemoglobin
for transporting oxygen but contain little
else. They lack a nucleus and most
organelles. Are red blood cells more or less
likely to be infected by a virus?
a) More likely
b) Less likely
B - don't have the machinery to replicate a virus' genetic material
99
COVID19
+ single stranded RNA virus, enveloped, spike protein on capsid surface recognizes and enters through the ACE2 enzyme (lung and other cells)
100
1. How does SARS-COV-2 genetic material get replicated?
a) Host cell DNA polymerase.
b) Host cell RNA polymerase.
c) RNA replicase encoded for by viral genome and built in the host cell.
d) RNA replicase encoded for by viral genome and originated from the
virus.
2. How does SARS-COV-2 proteins get built?
a) The host cell’s ribosome.
b) Ribosome encoded for by viral genome and built in host cell.
1. C
2. A
101
Phases of COVID 19 infection and immune response
1. Viral phase - immune system detects virus and WBC make antibodies which bind to spike and prevent it from attaching to ACE2
2. Hyperinflammation - immune system cannot create enough effective antibodies to combat the infection, system shifts into hyperinflammation causing serious symptoms and death
102
Pfizer and Moderna Vaccine
transmits the mRNA that codes for spike - body recognizes and cells make the spike protein and the cells make antibodies against spike
103
Johnson and Johnson Vaccine
uses double stranded DNA to teach body to make antibodies against spike
104
The Johnson and Johnson vaccine contains the DNA that codes the spike
protein. Moderna and Pfizer vaccines contain the mRNA that codes the
spike protein.
1. Once the JJ vaccine enters the human cells, what must happen in
order for a spike protein to be made?
2. Once the Moderna or Pfizer vaccine enters the human cells, what
must happen in order for a spike protein to be made?
a) DNA replication only
b) DNA replication, transcription and translation
c) Transcription and translation
d) Translation only
1. B
2. C
105
Why do RNA viruses mutate more quickly than DNA viruses?
Because DNA viruses use host DNA polymerase to replicate, DNAp can fix its mistakes via proofreading and the host cell will also use mismatch repair - basically it goes through the editing process of a human cell and RNA is more error prone because it has no editing mechanism
