Exam #2 - Lecture Notes 10-12 Flashcards Preview

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Flashcards in Exam #2 - Lecture Notes 10-12 Deck (233):
1

The SA to volume ratio becomes ______ as the cell gets bigger.

smaller

2

And when the SA to volume ratio is too small, you really lose the ability to ______ the cell's large volume.

nourish

3

Where is the central vacuole found?

Plant cells

4

What is the central vacuole going to do?

It's going to INCREASE the SA to volume ratio

5

True/false: Prokaryotes are single celled, whereas eukaryotes are multicellular.

FALSE, because there are single celled eukaryotes.

6

Prokaryotes are invariably...

single cellular

7

Achea tend to live in...

extreme environments...like a deep sea vent...like a hot spring...near boiling temperatures. A microorganism will THRIVE.

8

Besides the nucleus, where else is there DNA in a eukaryotic cell? And name one.

It's within organelles in the cytoplasm.
So DNA found in organelles.
Ex: mitochondria

9

What are the three main differences that distinguish prokaryotes and eukaryotes?

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

Do bacteria have DNA?

Yes, BACTERIA HAVE DNA! They have chromosomes!

11

Is the DNA in a bacteria enclosed in a membrane?

No

12

Where is the DNA in a bacteria located?

In a region of the cell wall called the "nucleoid"

13

What's the one feature you need to know about a bacterial cell?

They do not have membrane bound organelles

14

Which one has a cell wall?

BOTH

15

Bacteria have a cell wall, but so do many eukaryotes, although not all, not ________.

animals

16

Most DNA in eukaryotes is in the nucleus, so where is the rest of it?

The rest of it is found in organelles, such as the mitochondria

17

Common features of all cells...
ALL CELLS HAVE A ____ _________.

CELL MEMBRANE

18

What is the composition of that cell membrane?

Phospholipid bilayer

19

The cytoplasm is everything between the _______ ______ and the ____ ________.

between the nuclear membrane and the cell membrane

20

Everybody has PROTEIN, so everybody needs _________.

ribosomes

21

Again, what does the large central vacuole, found in plato cells, help to do?

Helps to increase the SA to volume ratio

22

What is the mitochondria for?

ENERGY. Sites of ATP synthesis

23

Eukaryotes are __x larger than prokaryotes.

10x larger

24

The ___ ______ maintains the internal chemistry of the cell.

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.