Exam #2 - Lecture Notes 10-12 Flashcards
(233 cards)
1
Q
The SA to volume ratio becomes ______ as the cell gets bigger.
A
smaller
2
Q
And when the SA to volume ratio is too small, you really lose the ability to ______ the cell’s large volume.
A
nourish
3
Q
Where is the central vacuole found?
A
Plant cells
4
Q
What is the central vacuole going to do?
A
It’s going to INCREASE the SA to volume ratio
5
Q
True/false: Prokaryotes are single celled, whereas eukaryotes are multicellular.
A
FALSE, because there are single celled eukaryotes.
6
Q
Prokaryotes are invariably…
A
single cellular
7
Q
Achea tend to live in…
A
extreme environments…like a deep sea vent…like a hot spring…near boiling temperatures. A microorganism will THRIVE.
8
Q
Besides the nucleus, where else is there DNA in a eukaryotic cell? And name one.
A
It’s within organelles in the cytoplasm.
So DNA found in organelles.
Ex: mitochondria
9
Q
What are the three main differences that distinguish prokaryotes and eukaryotes?
A
1) Eukaryotes have a nucleus
2) Eukaryotes have membrane-bound sub cellular structure
3) The size of eukaryotes tend to be larger.
Prok: 1-10 micrometers
Euk: 10-100 micrometers
10
Q
Do bacteria have DNA?
A
Yes, BACTERIA HAVE DNA! They have chromosomes!
11
Q
Is the DNA in a bacteria enclosed in a membrane?
A
No
12
Q
Where is the DNA in a bacteria located?
A
In a region of the cell wall called the “nucleoid”
13
Q
What’s the one feature you need to know about a bacterial cell?
A
They do not have membrane bound organelles
14
Q
Which one has a cell wall?
A
BOTH
15
Q
Bacteria have a cell wall, but so do many eukaryotes, although not all, not ________.
A
animals
16
Q
Most DNA in eukaryotes is in the nucleus, so where is the rest of it?
A
The rest of it is found in organelles, such as the mitochondria
17
Q
Common features of all cells…
ALL CELLS HAVE A ____ _________.
A
CELL MEMBRANE
18
Q
What is the composition of that cell membrane?
A
Phospholipid bilayer
19
Q
The cytoplasm is everything between the _______ ______ and the ____ ________.
A
between the nuclear membrane and the cell membrane
20
Q
Everybody has PROTEIN, so everybody needs _________.
A
ribosomes
21
Q
Again, what does the large central vacuole, found in plato cells, help to do?
A
Helps to increase the SA to volume ratio
22
Q
What is the mitochondria for?
A
ENERGY. Sites of ATP synthesis
23
Q
Eukaryotes are __x larger than prokaryotes.
A
10x larger
24
Q
The ___ ______ maintains the internal chemistry of the cell.
A
cell membrane/plasma membrane
25
One function of the cell membrane is that it maintains the internal chemistry of the cell.
What are two other main functions?
1) Receptors - receive signals in multicellular organisms...could be a hormone. Even in single celled life, can receive a signal from the environment. Receptors are part of that membrane.
2) Transport - What good is a barrier against atoms…? Against atoms…if we cannot bring in nutrients, if we cannot bring in sugar, if we cannot bring in amino acids. It’s useless. We have to have transport capability within that barrier, and we do and we have other functions as well.
26
We just said the membrane is more than a barrier! It has receptor capability! It has transport capability! Just to transport what you want, and not poisons and toxins. How do you have that functionality if you don’t have the best of all molecules…______.
PROTEINS.
27
Again, what is the composition of the cell membrane? (3)
Phospholipids, other lipids, *diverse proteins*
28
Why do we, eukaryotes, require membrane bound organelles?
The ability to compartmentalize certain functions so they don't get mixed up
29
Can bacteria make ATP
Of course, energy source
30
True/False: There was ATP being made by bacteria well before there was ever a eukaryotic cell.
True
31
Is the mitochondria essential to making ATP?
No, bacteria make it, but they do it in a small space...they're 10x smaller than euk's.
32
Why do we have organelles?
We have a huge volume compared to little bacteria
33
Organelles _________ nutrients.
concentrate nutrients, so that they can readily find the enzyme that will then convert that to something else
34
When we import glucose, we begin to catabolize, we begin to break it down...but VERY QUICKLY we begin to move it to the __________. Concentrate the sugar in _______ where it's rich, where enzymes can readily act upon it.
Mitochondria
35
So what is the purpose of the organelles?
Compartmentalization
36
We have organelles that are full of enzymes that will break through anything…expect the membrane that contains them. They can digest anything…that’s a dangerous organelle…we keep those enzymes locked up in _________.
lysosomes
37
What is the purpose of isolating biochemistry?
So it doesn't interfere with other parts of the cell
38
**Membrane is always going to provide _______.** So just as the cell membrane has additional functionality, so do the ________ membranes have functionality.
So they're not just barriers...they have function as well.
function, interior
39
All of the membrane bound organelles possess either ___ or ___ membrane. Either ___ or ___ lipid bilayer.
one or two
40
How many membrane does the nuclear envelope have?
Two membrane
41
How many membrane does the E.R have?
One membrane
42
How many membrane does the Golgi have?
One membrane
43
How many membrane does the mitochondria have?
Two membrane
44
All the organelles contain _______ solutions.
aqueous
45
Muscle cells are particularly _______ in mitochondria.
RICH, ABUNDANT...all true. They're LOADED with mitochondria because they need so much ATP. They depend upon ATP
46
Another cell, ____ metabolically active may not have so much mitochondria in it
less
47
In order for the nuclear pores to work, two membranes must...
come together, so the two membrane FUSE at the nuclear pores
48
What are the nuclear pores used for? Is there anything SPECIFIC that MUST pass through the nuclear pore?
RNA! RNA is made in the nucleus, but decoded in the cytosol. RNA must be exported though nuclear pores
49
EVERY ORGANELLE CONTAINS ________!
PROTEIN
50
DNA is wrapped around _____ proteins.
histone
51
Protein is made by the _______.
ribosome
52
A ribosome has ____ parts.
two
53
Two ______ make up the ribosome. One _____, one ______.
subunits, one large, one small
54
What are the two groups of ribosomes?
Free ribosomes - One group making protein in the cytosol
Bound ribosomes - Another group making protein on the surface of the E.R
**At any instant in time**
55
The endomembrane system is a system of membrane INSIDE the cell...that is _______ joined.
Indirectly
56
What does that mean, "indirectly" joined?
Indirectly joined in that, you can break off a piece here and send it over here
57
So in a sense, indirectly joined means breaking off a piece and sending it to another part of the membrane. And what is broken off and sent is called a _______ _______.
transport vesicle
58
What are the five parts of the E.M.S?
E.R, Golgi, lysosomes, food vacuoles, cell membrane
59
Why is the cell membrane part of the E.M.S? It's not really "endo" or "inside."
It's part of the E.M.S because it can bud off a vesicle
60
What is the E.R connected to?
Nuclear envelope, namely, the outer membrane of the nuclear envelope
61
How many membrane does the E.R have?
One membrane
62
What's the function of the E.R?!
TO MAKE PROTEIN! It's got ribosomes. Functioning ribosomes. They're in the process of making protein.
63
What happens to the protein? (According to that specific diagram?) It is threaded across the E.R membrane, into the internal space called the _______.
lumen
64
What is the interior of the E.R called?
The lumen
65
Where do the protein go?
Inside. So the protein was made here, it's threaded inside and there it is, *inside the E.R lumen*
66
The rough E.R also contains which type of proteins?
Chaperon proteins
67
Chaperons help proteins _____.
fold. Preventing undesired interactions from other proteins in that process
68
What happens to the protein once it folds and in the E.R lumen? WHAT HAPPENS NEXT?
What are the two possibilities?
1) The protein stays in the E.R. A ______ protein might stay in the E.R...CHAPERON PROTEIN. How does it get there? It's made by a ribosome.
2) The protein can leave the E.R.
69
How does the protein leave the E.R?
It can bud off in a transport vesicle. That is the only way to get out of the E.R.
70
In order to travel to another part of the endomembrane system, the only place this vesicle can go is to...
more E.M.S. For example, Golgi
71
What is a primary destination of vesicles leaving the E.R?
Golgi
72
What is the 'cisternae'?
The individual folds of E.R
73
What is the function of the smooth E.R?
To make lipids!
74
ALL of the lipids we have discussed...phospholipids, cholesterol, fats...all of that...biochemistry happens at the ________ ___...makes lipid.
Smooth E.R
75
What's another function of the smooth E.R?
Detoxifies toxic substances. Detoxifies drugs.
76
What's the exception to this?
It's a cell specific function.
77
True/false: All smooth E.R detoxify toxic substances.
FALSE. It's a cell specific function, NOT all smooth E.R detoxifies. Only some smooth E.R detoxifies.
78
For example...the smooth E.R found where?
In the human liver. The smooth E.R in the liver cells detoxifies.
79
Yet another function, and this is also a liver specific function...the smooth E.R...
stores glycogen, which is the storage polysaccharide. Smooth E.R stores it.
80
Where on the smooth E.R of the liver cells does the smooth E.R store the glycogen?
On the surface
81
Name all the functions of the smooth E.R
1) makes lipids
2) detoxifies toxic substances (cell specific function, typically in the liver cells)
3) stores glycogen, a storage polysaccharide (cell specific function, typically in the liver cells)
82
Name the functions of the E.R
Makes protein and lipid
83
What cell structure is made of lipid and protein that might well be manufactured by the E.R?
THE CELL MEMBRANE
84
The rough E.R is capable of dehydration to make what?
To make protein
85
The other one we've talked about is the _______. _______...FULL of ribosomes indicating that much protein is made within the _______.
cytosol
86
But also on the surface of the...
rough E.R
87
Remember, proteins that are actually made in the E.R actually end up within the E.R in an internal fluid filled space called the ______.
lumen
88
**How does a protein leave the E.R lumen?**
**In a transport vesicle**
89
Remember, the ______ _______ is what defines various membrane sin the ell as being part of the E.M.S. E.R, Golgi, lysosomes, food vacuoles, cell membrane....ALL components of the endomembrane system...which means they can 'bud off' membrane...and receive membrane between each of those structures...
transport vesicle
90
Cell membrane contains ______ and _______.
lipid and protein
91
The lumen is loaded with protein...what are the two options for the protein?
It can REMAIN there...again, could be chaperon protein.
| OR, it can LEAVE the E.R in a *transport vesicle*
92
So we said that one job of the E.R is to make ________, right? Rough E.R makes protein, smooth E.R makes lipid...so those are the two constituents of the ____ _________.
membrane, cell membrane
93
So how does a cell get big? How does it GROW?
By vesicles...as it obtains vesicles...
94
Where are the vesicles originally built?
E.R
95
So again, what's one job of the E.R?
To make membrane
96
Where do E.R vesicles go?
A primary route of traffic is to the Golgi. From the E.R to the Golgi
97
The Golgi apparatus has MULTIPLE ________ ____
flattened sacs
98
Each of these sacs contains _______.
Enzymes...which recall, run the biochemistry of the cell
99
And each sac...a ______ set of enzymes
different
100
And what the Golgi does is ______ vesicles...for example, from the E.R...it then _______ vesicles...from sac to sac. They're called ________. From ________ to ________. and eventually ___ ___ vesicles to other destinations.
```
receive vesicles
transmit vesicles
cisternae
From cisternae to cisternae
bud off vesicles
```
101
**So _______, ______ and ___ vesicles.**
Receive, transmit, and bud vesicles
102
The Golgi ______ E.R products.
processes
103
By process, we mean chemically _______.
chemically modify...covalently modifies E.R products. For example...oligosaccharides are added.
104
The Golgi is like an _______ _____ within the cell.
assembly line
105
Export is called ________.
secretion
106
Where do Golgi vesicles go? I think that's the next question. What are the two possibilities?
One possibility is to the *cell membrane. *
| Another possibility is to *lysosomes.*
107
Lysosomes are bodies capable of ____.
"lysis." It means cutting or breaking
108
What is export called?
Secretion
109
One destination is to the ____ ______, which results in _______ of those proteins.
cell membrane, secretion
110
A lysosome is a body containing lysis, or __________ enzymes
hydrolytic enzymes
111
A lysosome is a membrane bound ____, fluid filled and contains _______.
sac, enzymes
112
What do lysosomes do? What lysosomes do is to _____ to vesicles from the ____ ________.
fuse to vesicles from the plasma membrane.
113
What's the point to fuse with such a vesicle?
To digest whatever is in this vesicle
114
Sometimes we'll call these vesicles _____ _______.
food vacuoles, because what they brought in...is effectively food for the cell
115
How many membrane does Golgi have?
One membrane
116
How many membrane does a lysosome have?
One membrane
117
If this cell were an amoeba, you better believe that cell has _______. Remember that amoeba get their nutrients through this sort of import. Though* ___________.*They swallow other cells. Once they do, lysosomes go to town, digesting what's in that food vacuole.
lysosomes, endocytosis
118
Macrophage is literally a ___ _____.
"big eater"
119
_________ have also been shown to shallow and destroy cancer cells.
Macrophages
120
Another function of lysosomes is to...
break down a cell's own organelles
121
Why would you break down your own organelles?
It's a recycling mechanism. It's old...past it's time...lets break it down and recycle its component parts
122
Okay, again, a figure from another textbook showing this mechanism of lysosome function in a little bit more detail. So here is the lysosome, again…we said it _______ vesicles from the Golgi…right…here is the lysosome…now the lysosome has encountered a what? A ____ _______…from here…a _____ ______…and encountering it, the lysosome actually _____ with the food vacuole, exposing this food to the lysosomal enzymes.
RECEIVES, food vacuole, food vacuole, fuse
123
What is the purpose in sending protein to the lysosome? How does a lysosome get it's hydrolytic enzymes in the first place? What are hydrolytic enzymes, what kind of biomolecule is that?
Enzymes...PROTEIN...
124
How does a lysosome get protein? Where do these things come from?
THEY COME FROM THE GOLGI APPARATUS, YEAH!
125
Proteins leaving the Golgi, going to the lysosome are _______ protein to the lysosome.
DELIVERING
126
Lysosomes mediate __________ digestion.
INTRAcellular
127
Do not confuse digestion in the cell which occurs by ________, with digestion OUTSIDE of cells, which is what happens in your __ _____.
lysosomes, GI tract
128
This process of recycling the cell's components using lysosomes is called *________.*
Autophagy. It means just eating yourself
129
If a cell is specialized for secretion...specialized for export...it will be rich in ___ and it will be rich in ______.
E.R and Golgi, for the purpose of secretion
130
So macrophage will have a lot of ________, amoeba will have a lot of ________
lysosomes
131
Let’s tie up this section by once again recognizing there’s two sets of ribosomes found in the cytosol
* *One set is found drifting in the cytosol…not anchored to any surface…we call those ____ _______.**
* *The other set of ribosomes, in the cytosol, are bound to the surface of the E.R, we call them _______ ________.**
free ribosomes
| bound ribosomes
132
What are bound ribosomes for?
They're for making proteins for the E.M.S.
They’re making E.R proteins…for example, chaperons. They’re Golgi proteins…for example, the various Golgi enzymes…we said are found within those cisternae…where do they come from? THE ROUGH E.R, MADE BY BOUND RIBOSOMES.
133
Lysosomal ribosomes are made by _____ _______.
bound ribosomes
134
What about proteins that are found in the cell membrane? How do those get there?
They're made by a bound ribosome
135
Bound ribosomes also make proteins for ________.
secretion. Those proteins that are destined to leave the cell and function somewhere in the body…somewhere in the body outside of cells…such as digestive enzymes…such as antibodies…such as hormones, some of which are proteins.
136
What about free ribosomes? What do we need free ribosomes for? Make proteins for what?
For the CYTOSOL! THEY'REIN THE CYTOSOL AFER ALL.
137
What else do free ribosomes make protein for?
Mitochondria and chloroplast
138
Mitochondria and chloroplast get most of their proteins from the _______...import them from the _______.
cytosol
139
Recap of the E.M.S...
| They manufacture biomolecules - think _____ __ and _______ __
rough E.R, smooth E.R
140
They sort biomolecules - think _____ ______
Golgi apparatus
141
They ship biomolecules - again, _____ ______
Golgi apparatus
142
They export biomolecules - think _______ _______
transport vesicle
143
They import biomolecules - think _____ ______
food vacuole
144
They even recycle biomolecules - think _______ engaged in _______
lysosome engaged in autophagy
145
Mitochondria and chloroplast _____ energy
convert
146
True/false: The mitochondria and chloroplast are NOT parts of the endomembrane system
TRUE, they are NOT
147
***Since mitochondria and chloroplast are NOT parts of the endomembrane system, they cannot...***
they *cannot* bud or receive transport vesicles
148
They have their own ____ and _______.
DNA and ribosomes
149
What do you conclude about these organelles? They can contain DNA…they contain ribosomes…therefore they can make…_______. They can make _______. And this is the…third place…that you find ribosomes.
PROTEINS
150
So what are the three different ribosomes and where are they found?
Free ribosomes - found in the cytosol
Bound ribosomes - found on the surface of the rough E.R
Mitochondria and chloroplast ribosomes - found in the mitochondria and the chloroplast
151
Mitochondria and chloroplast don’t make all of their protein, but they make some of their protein. Most of their protein, in fact, is imported. Imported from the ______.
cytosol.
152
How many membrane does the mitochondria have?
TWO membrane
153
The mitochondria has two membrane...
An outer membrane, which has _______ structure.
An inner membrane, which is highly _______.
smooth, folded
154
Where is the ATP made?
Surface of the INNER membrane
155
Remember..._____...rich in mitochondria...____, does so much for our body...rich in mitochondria.
muscle, liver
156
What does the chloroplast do?
Makes sugar...makes sugar FOR the mitochondria
157
How many membrane surround the chloroplast?
TWO...hard to see
158
There's actually a third membrane floating around within the chloroplast, what is it called?
Thylakoid membrane.
159
Chloroplast is _____ than the mitochondria.
bigger
160
___________ theory is the origin of mitochondria and chloroplast.
Endosymbiont
161
So how do you get multiple membrane?
If you swallow a membrane bound structure...then you have additional membrane...that could explain how you have additional membrane in mitochondria and chloroplast
162
How do they grow?
They themselves divide, like a fission process
163
What does "semi-antonymous" mean?
It's a reference to the possession of DNA, and to the ability to divide
164
What is it that gives cells such broad shape?
Cytoskeleton
165
What is the cytoskeleton made of?
PROTEIN
166
How do vesicles travel about the cell? From the E.R to the Golgi, from the Golgi to the cell membrane…it’s not just diffusion…they’re moving along __________ ______ like a…train on tracks…like a train on tracks…it’s like a cable…moving along…
cytoskeletal fibers
167
Also provides _______. The cell itself can move. You've seen the flagellum, that is an extension of the cell skeleton.
motility
168
Last but not least…the cell skeleton can reorganize itself…It can reconstruct itself into specialized structures for a particular purpose…so it’s _______.
dynamic
169
There are _____ components of the cell skeleton.
three
170
What are the three components of the cell skeleton?
Microfilaments, intermediate filaments, microtubules
171
What is the diameter of a microfilament?
7 nm
172
What is the diameter of an intermediate microfilament?
8-12 nm
173
What is the diameter of a microtubule?
25 nm
174
Microfilaments are made of _____
actin
175
Intermediate filaments are made of ______
keratin
176
Microtubules are made of ______
tubulin
177
__________ have a role in CELL DIVISION.
MICROTUBULES
178
__________ grab the chromosome and pull them apart.
Microtubules
179
It's the microtubules that make up the structure known as the "_______ _______."
mitotic spindle. Pulls apart the chromosomes.
180
The proteins of _________ are made by ribosomes floating free in the cytosol.
mitochondria
181
Mitochondria are able to make some of heir own proteins because they posses ____
DNA
182
Which ribosomes make lysosomal enzymes?
Ribosomes on the E.R
183
Pancreatic enzymes are secreted into the small intestine where they help to break down carbohydrates, proteins, and lipids for absorption. Pancreatic cells must be particularly rich (abundant) in ___.
E.R
184
Digestion in the GI tract does NOT involve ________.
lysosomes
185
What type of interaction holds the phospholipid bilayer together?
Hydrophobic interactios
186
It was also understood that the membrane contains ______.
Protein. RICH in protein.
187
What did the fluid mosaic model say about the location of protein?
it said that the protein is often *embedded*…embedded in the lipid bilayer. It may be embedded partially…it may be embedded completely, so that it completely spans the membrane, from one side to the other. It completely spans, it’s TRANSMEMBRANE in its position.
188
How a protein is arranged, with respect to the membrane, will depend upon its ______ _____ makeup
amino acid
189
Membrane also has _______
SUGARS
190
Where are sugars attached?
Sugars are attached to protein on the outer layers of the membrane
191
So if you were to bump into a cell, the first thing you may encounter is a ______
sugar
192
What's the importance of the sugars on the surface of the cell?
The sugar gives the cell its *IDENTITY*
193
Sugars lead to identification of...
self
194
Phospholipids are moving ________.
laterally
195
Why can't phospholipids flip flop?
Flip flopping means taking the hydrophilic head through the hydrophobic core. "Highly unfavorable."
196
Can proteins move laterally?
Yes
197
Fluidity is essential...why?
| The fluidity will allow tiny ____ to form...where maybe small molecules can move across.
gaps
198
What influences fluidity?
Temperature
199
As temperature increases, fluidity _______***
INCREASES. More thermal energy, more diffusion.
200
As temperature decreases, fluidity ________***
DECREASES
201
Another fact that increases fluidity is the precise chemistry of ______ ______
fatty acids
202
If the temperature is too hot, what can you do?
Make more SATURATED fatty acids
203
Making more saturated fatty acids will make the membrane more _______.
viscous, helping to balance out that higher temperature
204
If the temperature were to go down, what would you do?
Make more UNSATURATED fatty acids
205
________ also helps to control fluidity.
Cholesterol
206
Cholesterol, recall has that ____ ring steroid structure.
four
207
What is that little head on the cholesterol?
HYDROXYL GROUP
208
In that position, the phospholipids are prevented from packing too tightly, so the membrane does not become too _______. At the same time, the phospholipids are restricted in their ability to dance around.
viscous
209
So cholesterol helps to keep it in the middle. Prevent the membrane from being too ______ or too ___.*** Just right.
vicious, fluid
210
Every membrane has its own set of ______...specific for that organelle
proteins
211
The proteins can be embedded into the hydrophobic core…or they can be restricted to a surface…***if they’re embedded, we call them ***______ membrane proteins***…if they’re restricted to a surface, we call them ***________ membrane proteins.***
integral, peripheral
212
Integral…yeah…this is integral, this is integral. These are not only embedded, they’re spanning the membrane, **they’re __________**…recall that.
transmembrane
213
Again, these oligosaccharides, which are joined to proteins…**GIVE THE CELL ITS _______.** Allowing your body to distinguish the self from the microorganism
IDENTITY
214
Do animals have a cell wall?
NO
215
Do animals have a cell wall? NO. **But we do have a carbohydrate rich structure beyond the cell membrane…that’s called the _____ _________ ______.**
extra cellular matrix
216
The ________ _______…***the _________ ________…meaning the amino acid makeup of the protein will determine its precise disposition within the membrane***
primary structure
217
The membrane proteins have precise _________.
orientation
218
Which proteins join one cell to another? (**Exam**)
Cell junction proteins
219
So what is the answer then forming things across the membrane?
The proteins are going to be an indispensable part of transporting substances across the membrane
220
The membrane is ________ permeable
selectively
221
**A pure bilayer will allow _____ and ______ molecules to cross easily.**
Like who?
Small and non polar.
| Ex: Oxygen, CO2
222
***If you are _____ and _____, you will be partially blocked.***
Like who?
small and polar.
| Ex: water (H2O)
223
***If you are _____ and _____, forget it...you are totally blocked.***
Like who?
Large and polar
| ex: glucose
224
***If you are _____, YOU ARE TOTALLY BLOCKED.***
charged
225
Oxygen comes right in…we need that in abundance…okay, no problem…glucose, we also need that in abundance…it can’t get in, right? Sodium, potassium, electrolytes…we need to move them across, we cannot move across.
So…the second consideration is…***there are _______ ______.***
transport proteins
226
What is diffusion?
Random movement from an area of high concentration to an area of low concentration
227
What if it's at low concentration but you need it now? In those situations, there is a way to push it across the membrane...effectively concentrating it within the cell, and that is known as _______ ______
Active transport
228
In passive transport, there is no _____ of energy.
input
229
In active transport, there is _____ of energy to movement from ___ to ____.
input, low to high
230
Notice that, even though you're going high to low, you can even go the other way...yeah, this guy here is going the other way because it's _______.
RANDOM, random movement
231
This is NOT chemical equilibrium, this is called _______ equilibrium
difffusion
232
Passive transport DOES involve ______, but there is NO INPUT of energy.
Energy, thermal and potential
233
What are the two types of diffusion?
Simple diffusion - movement directly across the lipid bilayer. Must be small and non-polar
Facilitated diffusion - if you are polar and/or charged, you can diffuse, but you need a transport protein.
