Exam 2 Flashcards
1
Q
What is the sum of chemical reactions inside a cell?
A
Metabolism
2
Q
What is a catabolic reaction
A
breaks down complex molecules into simpler ones (hydrolysis)
3
Q
What is an anabolic reaction?
A
build up molecules from simpler ones
4
Q
Which reaction releases energy?(exergonic)
A
catabolic
5
Q
which reaction requires energy? (endergonic)
A
anabolic
6
Q
What is energy?
A
the capacity to do work
7
Q
What is the difference between kinetic and potential energy?
A
kinetic is movement (ex: thermal E)
potential is position( ex: chemical E)
8
Q
What is the study of energy?
A
thermodynamics
9
Q
what is the first law of the conservation of E
A
the amount of energy in the universe is constant, energy cannot be created or destroyed
10
Q
what is the second law of the conservation of E
A
every energy transformation involves an increase in entropy(s) = the amount of disorder in the universe.
11
Q
is water evaporating an increase in entropy?
A
yes
12
Q
what process creates a decrease in entropy because it must input energy?
A
anabolic
13
Q
what does chemical reactions in cells do?
A
power life
14
Q
What is gibbs free energy
A
the energy that is available to do work
15
Q
Change in Delta “G” =?
A
Gproducts- Greactants types: if negative( - ) releases E, spontaneous, exergonic if positive( + ) requires energy, non. spon. endergonic if 0 equilibrium, cannot do work.
16
Q
what do spontaneous reactions drive?
A
non spon reactions
ex.) catabolic reactions release E–> feeds into anabolic rxns that require E
17
Q
Delta G tells you nothing about what?
A
the speed of the reactant
18
Q
What is activation Energy?
A
- the Energy needed to reach transition state.
- It breaks old bonds and makes new ones
19
Q
E,activation = G trans st. - ___________?
A
G reactions
20
Q
The larger the activation energy the _________the reaction
A
slower
21
Q
Enzymes are catalyst, what do they do?
A
they speed up a reaction Without being consumed.
22
Q
Do enzymes change the delta G value?
A
NO
23
Q
Do enzymes reduce Activation energy?
A
YES
24
Q
Fig 3.13
A
look up
25
How do enzymes lower Activation energy?
the enzymes active sight binds a reactant(substrate) through multiple weak/temp interactions that form through spontaneous exergonic rxns that feed into lowering Eact.
- this accounts for enzyme specificity
26
Metabolic pathways.
1. ) ______ and _________ pathways consist of series of chemical reactions.
2. ) The____ of one reaction is the ________ for the next reaction?
3. ) how does a cell maintain a constant environment with all this chem activity?
1. catabolic, anabolic
2. product, substrate
3. regulation of enzymes
27
How do you regulate the metabolism by regulation of Enzymes?
1. ) change the amount of enzyme
| 2. ) change the activity of enzyme
28
which inhibitors bind permenantly to the active site of an enzyme and completely shut off the enzyme activity?
irreversible inhibitors
29
which enzymes bind to an enzyme through temporary, non- covalent interactions?
reversible inhibitors
30
Which inhibitor is similar in shape of the substrate and blocks it from binding?
competitive
31
which inhibitor does not bind to an active sight and when it binds to the enzyme it cuases the enzyme to change shape?
What non- competitive
32
What does Allo/steric mean?
Allo= different
| steric=shape
33
Allosteric regulation
1. which regulation is non-competitive inhibitors?
2. which is allosteric activators?
1. negative regulation
| 2. positive regulation
34
How do regulator molecules bind?
through non covalent and covalent attachment
non covalent = attaching a larger regulatory molecule GTP & ATP
covalent = attaching a phosphate enzyme
35
what Is feedback inhibition?
product of the reaction inhibits the enzyme. (competitive inhibition)
36
What are the regulations of the environment?
pH. and temperature
37
what happens in pH inhibition?
all enzymes have an optimum pH
| higher or lower enzymes can affect the enzyme and make it unfold and lose structure
38
what happens in Temperature inhibition?
enzymes have an optimum temp.
to high= denature
to slow= slows enzyme
39
co factors
help enzyme do its job, non protein partners. Metal ions are z2+ Fe2+ Fe3+
they are large molecules that temporarily bind to the enzyme
prosthetic groups - bind to enzyme permanantly
40
Chemical regulation is often the form of__________
inhibitors
41
When you determine the shape of the substrate you should first______________
determine the shape of the inhibitor
42
you can observe a _________ by adding more_______
competitive inhibitor, substrate
43
___________ inhibitor can be over come by the addition of more substrate
non competitive
44
in __________- we break _______________-- which result in an explosion of energy
digestion, covalent bonds
45
What are the three steps of cell theory?
1. cells are the fundamental (smallest) units of life
2. all living things are made of cells
3. all cells come from pre existing cells
46
1600 microscopes were invented.
1. ) Schleiden (botanist) honored with____________
2. ) Schwan (physiologist) described______________
connection as cells being living
| 2 several different types of animal cells
47
Why are cells small?
maximize SA: Volmume ration
48
What does surface area on a cell determine
import and export rates
49
what does volume determine on a cell membrane?
metabolic activity
50
All cells have
plasma membrane, cytosol, DNA, ribosomes
51
ribosomes can be ______,_________,__________________
free, bound, made of rRNA + several small proteins
| proteins are referred to as scaffolding.
52
What does rRNA do? what do proteins hold together?
synthesizes proteins. ribosomes
53
what are prokaryotic features?
```
nucleoid
cytoskeleton= protein filaments
only in some:(below)
cell wall= peptidoglycan
capsule= slimy layer of carbs
flagella = flapping appendage
```
54
what is in the endomembrane system?
```
nucleus
ER
Golgi
lysosomes
Plasma membrane
vesicles
(all are bud infused)
```
55
What do transport vesicles do? what is the outside and inside called/?
transport protein, cytosol, lumen
56
what is the difference between chromosomes and chromatin?
```
chromosomes = just DNA
CHromatin = DNA + packaging protein there role is for DNA condensing
```
57
what is the function of a nucleus
DNA replication
RNA transcription
make ribosomes
58
where are ribosomes made?
nucleolus - double membrane with nuclear pores
59
WHat does the Nucleus connect to ?
ER which have lots of SA
60
Why is the Rough ER rough? Ribosomes are and are joined through?
There are ribosomes on it, protein factories, dehydration
61
The smooth ER produces____________ and is the store house for __________
lipids and steroids, Ca^2+
ex. sacroplamic ret. = detox
ex. H2O2
62
What is the function of the Golgi apparatus?
protein modification & sorting
| Modification = covalently attaching chemicals to proteins, proteins = carbs
63
Does the Golgi have polarity? is it attached?
yes and no
64
what happens in the vesicular transport model?
vesical fuses to cis face. buds off working through Golgi, once all the way through it leaves. Fig. 4.9
65
Lysosomes are full of _________
hydrolytic enzymes, go through hydrolysis reaction
66
what is the pH of the lumen and cytosol in a lysosome?
4, 7.2
67
Lysosome
mem have h+ pump protein
-optimal pH enzymes work best at
-the pH 4 protects cytosolic molecules from digestion if lysosome bursts
-
68
The greater the H the more ________- the environment becomes in a lysosome
acidic
69
_________- is when a cell brings in external materials for digestion through a phagosome
phagocytosis
70
what is a primary 1* lysosome/
buds from the trans face of Golgi
| -fusion of phagosome to 1* lysosome = 2* lysosome
71
_______ is when lysosomes pick up and clean up old work out organelles, break them down and recycle
autophagy
72
Mitochondria (power house) deals with
cellular respiration
73
What is the mitochondria's structure ? why is the matrix folded for max SA?
```
Inner membrane
matrix :
-2nd cell that contains DNA( a little)
-ribosomes
-enzymes
it is folded because the more SA the more ATP that an be produced for cellular respiration
```
74
Chloroplasts contain _______
chlorophyll which absorbs light and turns it into chemical energy
75
structure of chloroplasts
inner and outer membrane
thylakoid - where photosynthesis occurs
granum = stacks
stroma = liquid
76
peroxisomes are parnters with the _______ ER and help in detox. they accumulate ______- and make _________
smooth, h2o2, H2O
77
are vacuoles are larger in plant or animal cells?
plant take up 90%
78
Vacuoles in animals are
food vacuoles
79
vacuoles in plants
```
storage
-waste
-poisons or bad tasting compounds
-pigments
-cell growth/elongation
=turger pressure filaments of plant
```
80
what is the function of a Eukaryotic cytoskeleton?
support, motility
81
what are microfilaments? what do they do?
thin, solid rods, made of protein called actin
- support cell shape
- amoeboid movement
- work with motor protein myosm to cause muscle contraction
82
where do active filaments tend to lye?
just inside cell membrane
83
Intermediate filaments are? and do _______?
tough rope like materials
- made up of karatin
- helps cell to withstand mechanical stress
- remain in tact after cell death
84
what are microtubules? and their functions?
thick hollow tubes of tubulin
- guide organelle movement
- separation of chromosomes I mitosis
- cilia and flagella******special
85
what is the order in diameter from biggest to smallest of microtubules, microfilaments, and intermediate filaments?
Microtubules, intermediate, microfilaments
86
Cell wall is made up of______________ which is strong and fibrous.
cellulose: cell wall is also known as the skeleton of the plant cell.
87
plasmodesmata are_________ that help the plant cell to share ________ and C_________
cytoplasmic pores, nutrients, communicate
88
The Extracellular Matrix has secreted _______ that realeas _______ to outside the cell
proteins fig. 4.17
89
What is the rold of the ECM
protection
- holds cells together to make tissues
ex. epithelial tissue
90
What are the three types of junctions in the ECM
tight, desmosomes, gap junctions
91
what is a tight junction in the ECM?
seals cells so tightly that even fluid cannot pass between them.
92
what are desmosomes junctions?
additional support to hold cells together, withstand mechanical stress.
93
what are Gap junctions in the ECM?
cytoplasmic pores
94
what are phospholipids?
amphipathic molecules
form a bilayer
have non polar hydrocarbon tails away from water and
expose hydrophilic head groups to water.
95
Is cholesterol hydrophobic?
most of it is except its OH group
96
what is the most common length of a phospholipid tail?
a. ) 16-18
b. ) 17-24
c. )14-15
a.)16-18
97
what does the length of a tail mean on a phospholipid/
```
longer= less fluid(solid/gel)
shorter= more fluid
```
98
what is the difference between saturated and unsaturated phospholipid tails?
saturated(no C=C double bonds) less fluid
| unsaturated( has C=C db bonds) more fluid
99
what maintains membrane integrity in extreme temperatures?
cholesterol
100
where is cholesterol packed?
between phospholipids.
101
where is cholesterol packed?
between phospholipids.
102
Low temp = what for cholesteraol and PL tails?
cholesterol= antifreeze
| prevents PL's from packing to close
103
High temp = what for cholesterol and PL tails
cholesterol = glue
| hold's PL's together to prevent melting of the membrane.
104
__________- are carbohydrates covalently attached to a lipid embedded in the membrane.
glycolipids.
105
__________ are carbohydrates covalently attached to a membrane protein
glycoproteins.
| poteoglycons - long carb train attached to protein
106
function of membrane carbs
cell to cell recognition.
signaling sites
cell-cell adhesion
107
what is audity?
the movement of molecules through the membrane
108
what is the lateral diffusion?
move side to side. Very fast. 10^7 ties per second
109
what is flip flop diffusion
movement from one leaflet to another.
happens like once per month
not favorable for hydrophobic head to move through hydrophilic tails. (enzymes would be required to make this happen faster)
110
fluidity is determined by...
unsat and sat fats.
1. % of unsat and sat fats
2. increase amount of cholesterol = more solid membrane
3. increase amount of protein = more solid membrane
111
what type of diffusion is spontaneous and does not require energy?
passive
112
what is diffusion?
the tendency to spread out.
113
what are affecting factors of diffusion?
smaller size = faster diffusion
higher temp = faster diffusion
high concentration = low diffusion
114
what is concentration gradient?
two areas w different solute composition.
115
simple diffusion
solutes are hydrophobic
116
facilitated diffusion
solutes are hydrophilic. and require transport proteins.
117
what is osmosis?
passive transport across a membrane
| h20)high-->H20(low
118
what is hypertonic? what is another name for it?
high solute outside so H20 moves out(shrinks)
| Crenate= shrink
119
hat is hypotonic? and another name for it?
low solute outside, H20 moves in
| lyse = burst
120
what is Isotonic?
solute on outside = solute on inside
121
what are channel proteins?
hydrophilic tunes
can be gated open/close based on a stimulus
s
122
what are carrier proteins?
bind the transported substance
| proteins change shape upon binding to transported molecule
123
What is active transport?
it occurs from low--> high and is non spontaneous
124
Primary active transport
E source is ATP (chem energy for cell)
125
when you change the shape you change the_________
function
126
what is Phosphorylation?
when you add a phosphate group
127
on ATP are the bonds high energy and unstable?
yes
128
what are synonyms for Secondary active transport?
co transport, couple transport
129
secondary active transport what is it?
when passive transport powers the active transport?
130
what is phagocytosis/
"cellular eating" bring substance in through phagosome and fuses with lysosome so contents are digested.
131
what is pinocytosis?
"cellular drinking" continuous spontaneous non specific intake fluids disovled in substance
132
what is signal transduction pathway?
1. ) reception- cells will bind a signal from outside cell
2. ) transduction - domino pathway sets of chemical reactions in cell(allosteric affect)
3. ) response - cell changes its behavior.
133
types of signals are
1. ) Local -
2. ) long distance -
1. ) autocrine - cell talks to itself
| 2. ) procrine - signals nearby cells
134
types of receptors
1. )cytosolic
2. )cell- surface
1. ) receive hydrophobic signals - easily pass thru membrane
- effect = sent to nucleus change gene expression
2. ) cell - surface receptors
- recieive hydrophilic signals
- effect = receptor changes shape and triggers internal cascade
