Organelles and Energy Flashcards
1
Q
what type of cells are 10 times larger than prokaryotic, have membrane enclosed compartments called organelles, and have a protein scaffolding called the cytoskeleton
A
eukaryotic
2
Q
what does a plant cell have that an animal doesn’t
A
cell wall (cellulose)
chloroplast
vacuole
3
Q
what is the largest organelle
A
nucleus
4
Q
nucleus characteristics
A
- contains the DNA
- Site of DNA replication
- Site of genetic control of cell activities
- the nucleolus begins assembly of ribosomes
5
Q
what is the two membranes the nucleus is surrounded by
A
nuclear envelope
6
Q
what is in the envelope control passage of molecules; large molecules, such as proteins, need a signal to pass through
A
nuclear pores
7
Q
DNA combines with proteins (histones) to from __ in the nucleus
A
chromatin
8
Q
what are separate strands of chromatic, which package tightly before cell division
A
chromosomes
9
Q
site of protein synthesis
A
ribosomes
10
Q
are ribosomes in both prokaryotic and eukaryotic cells
A
yes
11
Q
in eukaryotic cells, ribosomes can be
A
- free in the cytoplasm (all protein synthesis starts on free ribosomes in the cytosol)
- attached to the ER (RER)
- inside mitochondria and chloroplasts
12
Q
what system includes the nuclear envelope, ER, Golgi apparatus, and PM
A
endomembrane system
13
Q
the outer membrane of the nuclear envelope is continuous with the
A
endomembrane system
14
Q
a network of interconnected membranes including the RER and SER
A
endoplasmic reticulum
15
Q
RER characteristics
A
- some ribosomes attach to the RER
- newly made proteins enter the lumen and can be modified and transpoted
16
Q
what receives proteins from the RER and can modify them and packages and sorts proteins
A
Golgi apparatus
17
Q
what originates from the golgi apparatus, contain digestive enzymes to hydrolyze macromolecules into monomers
A
lysosomes
18
Q
what to plant cells have instead of lysosomes
A
vacuoles
19
Q
how do food molecules enter the cell
A
phagocytosis
20
Q
what is phagocytosis
A
a phagosome is formed which fuses with the lysosomes
21
Q
what is autophagy
A
lysosomes also digest cell materials
22
Q
what type of transport is exocytosis and endocytosis
A
active tansport
23
Q
some proteins contain a _____ within their amino acid sequence (an address label that identifies where the polypeptide belongs
A
signal sequence SS
24
Q
what does SSRER do
A
temporarily stops translation and sends the ribosome to the ER to complete translation
25
if a protein only just the SSRER sequence it is ____
secerted
26
no signal peptide
sent to cytosol
27
amino terminal signal
sent to chloroplast and mitochondrion
28
internal signal
sent to nucleus
29
if the protein is sent to the ER: signal sequence binds to a ____________ before translation is done
signal recognition particle (SRP) floating in the cytosol
30
In the _____, energy in fuel molecules is transformed into the bonds of energy rich ___: cellular respiration
1. mitochondria
2. ATP
31
the inner membrane of the mitochondrion folds inward creating
a large surface area for proteins that participate in cellular respiration reactions
32
the mitochondrial matrix contains
DNA and ribosomes
33
mitochondria have a __ membrane
double
34
1. site of photosynthesis
2. have a double membrane
3. contain ribosomes and DNA
4. Thylakoids - flat circular compartments of an inner membrane
chloroplasts
35
what theory explains how eukaryotes could evolve from prokaryotes: cells engulfed other cells that became mitochondria and chloroplasts
endosymbiosis theory
36
the capacity to do work, or the capacity to change
energy
37
what are energy transformation linked to in cells
chemical transformation and molecular movement
38
what are the two categories of energy
potential and kinetic
39
what is potential energy
the stored energy - as chemical bonds, concentration gradient, charge imbalance
40
what is kinetic energy
the energy of movement
41
1. what captures and transfers energy
2. releases a large amount of energy earn hydrolyzed
3. donate phosphate groups to other molecules
ATP (adenosine triphosphate)
42
bonds linking phosphate groups have high ____ energy
potential
43
the set of life sustaining chemical reactions occurring in cells of organisms
metabolism
44
what is the first law of thermodynamics
energy is neither created nor destroyed
45
when energy is converted from one form to another, some of that energy becomes unavailable to do work
second law of thermodynamics
46
a measure of disorder in a system
entropy
47
living organisms must have a constant ________ to maintain order
supply of energy
48
change in free energy in a reaction is the difference in free energy of the
products and reactants
49
change in G = change in H - T change in S
if change in G (free energy) is negative, free energy is released
-spontaneous reaction (exergonic)
if change ing G is positive, free energy is consumed
-reaction is not spontaneous (endergonic)
50
if a chemical reaction increases entropy the products will be _____ disordered
more
51
1. catabolism
2. anabolism
1. - change in G
2. + change in G
52
the products have less energy that the reactions and disorder increased
free energy is released
53
Examples of exergonic reaction
cell respiration and catabolism
54
examples of endergonic reaction
active transport
cell movements
anabolism
55
______ increase the rate of a reaction
catalysts
56
most biological catalysts are _____ (protein) that act as a framework in which reactions can take place
enzymes
57
the amount of energy required to start a reaction
activation energy (larger the E the slower the reaction)
58
in a catalyzed reaction an enzyme ___ the reaction by reducing the activation energy
accelerates
59
activation energy changes the reactants into unstable forms with higher free energy
transition state intermediates
60
enzymes lower the energy barrier by
brining the reactants together
61
an enzyme forms a _____ with its substrate with turns into the product
complex
62
a complex can promote the reaction of two substrates by _____ their reactive groups and _______ their motion
aligning and limiting
63
the ____ may change when bound to the substrate, but eventually return to its _______ form
enzyme and original
64
enzymes _____ substrate molecules, bringing together the atoms that will bond
orient
65
biological catalysts are
highly specific
66
substrate molecules bind to the ______ of the enzyme
active site
67
the _____ shape of the enzyme determines the specificity
3-D
68
T or F: protein folding brings specific amino acids close to each other to form the active site
T
69
shape of enzyme active site allows a specific ______ to fit
substrate
70
what does the rate of a catalyzed reaction depend on
substrate concentraition
71
concentration of an enzyme is usually much _____ than concentration of a substrate
lower
72
at ______ all enzyme is bound to substrate - reaction at a maximum rate
saturation
73
every enzyme is most active at a particular_____
pH
74
what it pH
influences the ionization of a functional group
75
does every enzyme have an optimal temp
yes
76
do noncovalent bonds begin to break at a high temp
yes
77
what is it called when an enzyme loses its tertiary structure
denatured
78
enzymes that catalyze the same reaction but have different properties
isoxymes
79
regulates enzymes: molecules that bind to the enzyme and slow reaction rates
inhibitors
80
naturally occurring ____ regulate metabolism
inhibitors
81
what are the two types of inhibitors
irreversible inhibitor
reversible
82
inhibitor covalently bonds to side chains in the active site - PERMANENTLY inactivates the enzyme
irreversible inhibitor
83
Inhibitor bonds noncovalently to the enzyme inhibiting its function and reducing the rate of the reaction
reversibel inhibitors
84
bind to the enzyme active site competing with the natural substrate
competitive inhibitors
85
bind to the enzyme at a different site (not the active site)
the enzyme changes the shape and it actively reduced
non competitive inhibitors
86
"different shapes"
allostery
87
activators bind to ____ the enzyme
inhibitors bind and _____ enzyme funtion
stimulate
inhibit
88
reactions are organized into ________ and each reaction is catalyzed by a specific enzyme
metabolic pathways
89
what is the most common fuel in organisms
glucose
90
All cells use ______ and it is where glucose is converted to pyruvate, ATP and electron carriers
glycolosis
91
convert pyruvate into CO2, ATP and electron carriers
pyruvate oxidation and Krebs cycle (citric acid cycle)
92
converts electron carriers and O2 into ATP and H2O
electron transport chain
93
Aerobis
O2 present (cellular respiration)
94
anaerobic
O2 absent
95
what happens external to the mitochondrion
glycolosis
96
what happens in the inner membrane of the mitochondrion
electron transport chain
97
what happens in the matrix of the mitochondrion
citric acid cycle and pyruvate oxidation
98
what is an electron carrier in redox reactions
NADH
99
two forms of NADH
oxd - NAD+
red - NADH
100
glucose = 6 carbons pyruvate = 3 carbons
2 pyruvates
101
where does glycolysis take place
cytosol
102
what does glycolysis do
converts glucose into pyruvate
releases small amount of energy (2ATP and 2NADH)
generates no CO2
103
energy investing reaction
use ATP
104
energy harvesting reactions
produce ATP and NADH
105
what is phosphorylation
addition of a phosphate group
106
the formation of ATP by the transfer of a phosphate group from an organic donor molecule to ADP is called
substrate level phosphorylation
107
Input : Glucose, NAD+, ADP+Pi
output: 2NADH, 2ATP, 2 pyruvate
108
1. links glycolysis and the citric acid cycle
2. takes place in the mitochondrial matrix
3. pyruvate is converted to acetyl CoA
4. CO2 and NADH are produced
pyruvate oxidation
109
1. Acetyl CoA is starting point
2. completing the oxidation of glucose: the remains carbons are converted to CO2
3. Outputs: CO2, reduced electron carriers (NADH and FADH2), and GTP
citric acid cycle
110
Each glucose yeilds
6CO2
10NADH
2FADH2
4ATP(32 from ETC)
111
ATP is synthesized by the oxidation of electron carriers in the presence of O2
(two components)
1. electron transport chain
2. ATP synthesis powered by proton diffusion
oxidative phosphorylation
112
Electrons from NADH and FADH2 pass through the ______ of membrane associated carriers
ETC
113
where is the electron transport chain located
in the inner mitochondrial membrane
114
_______ is released as electrons are passed between carriers
energy
115
energy is released at ________ of ETC
each step
116
protons accumulate in the inter membrane space and create a
concentration gradient and charge difference
117
the ____________ drives the protons back across the membrane
electrochemical gradient
118
protons diffuse back into the mitochondria through ATP synthase, a channel protein
ATP synthesis
