Biology Exam 2

Front 1

In animals, are the outside of the cell rigid?

Back 1

No, they are not rigid

Front 2

Why are the outside of animal cells not rigid?

Back 2

Mainly to hold one cell to the next cell.

Front 3

What is the glue substance that holds the cells together in animal cells?

Back 3

glycocalix

Front 4

What is the glycocalix made ofand what is it's texture?

Back 4

Proteins modified with sugar.
1.) Fibronectin
2.) Collagen
-Slimy texture

Front 5

What keeps the animals cells together? Binding to one another and allow communication?

Back 5

1.) Tight Junctions
2.) Desmosomes
3.) Jap Junctions

Front 6

What are Tight Junctions?

Back 6

1.) Prevent extracellular material from infultrating the cell.
"Barriers"

Front 7

What are Desmosomes?

Back 7

1.) Fuzzy Rivets
Protein material that rivet cells together.

Front 8

What are Jap Junctions?

Back 8

"Analagous to Plasmodesmata"
-Little pores that allow the pentration of small solutes from one cell to the next.
"Act as Communication channels"

Front 9

What is the primary function of the plasma membrane?

Back 9

Separates the inside of the cell from the outside world.

Front 10

What are the major components of the Plasma membrane?

Back 10

1.) Phospholipids
2.) Cholesterol(animal cells)
3.) Proteins

Front 11

Why are Phospholipids so important to the structure?

Back 11

- Capability to form membrane bilayers.

Front 12

What two properties make the bilayer so important?

Back 12

Because the Phosphate head is hydrophilic and will interact with water.
Tails are hydrophobic

Front 13

How wide is the membrane bilayer?

Back 13

8 nanometres in width

Front 14

What is a mosaic?

Back 14

-Mixture of proteins of different types in the phospholipid bylayer.

Front 15

What are integral proteins?

Back 15

intergrated in the P bilayer

Front 16

What are peripheral proteins?

Back 16

on the outside of the P bilayer

Front 17

What are unilameller proteins?

Back 17

imbedded in only one half of the bilayer

Front 18

How are the proteins organized in, on and around the P Bilayer?

Back 18

-from the perspective of the proteins, they are ASYMMETRIC
-Outside proteins and outside material is different from the inside.

Front 19

What major feature does the membrane bilayer have that allow the proteins capability to move through the bilayer?

Back 19

-Membrane is neither solid nor liquid. It is a compromise between fluidity and structural integrity
-SEMI-FLUID STATE

Front 20

What is the function of cholesterol in the P bilayer?

Back 20

Function of cholesterol is the modulate the semi- fluid state in animal cells. Fluidity Buffer

Front 21

What distinguishes different cells from one another? Eg-Human from Mouse cell

Back 21

Signal Proteins on the membranes

Front 22

What is cell fusion? Eg-Hybrid cells

Back 22

-Experiment to show that proteins have the ability to move along the cell membrane. Eg-Human/Mouse cell fused to target signal protein movement

Front 23

What structure of the proteins are important to the cell membrane?

Back 23

Tertiary structure

Front 24

Why is tertiary structure important to the embedded protiens.

Back 24

Hydrophobic vs Hydrophilic amino acids. Hydrophobic part is on the inside and hydrophililc on the outside.

Front 25

What end of the protein is on the extracellular side of the membrane?

Back 25

N-terminus (HydroPhillic)

Front 26

What end of the protein is on the Cytoplasmic Side.

Back 26

C-Terminus. (Hydrophobic)

Front 27

What are the properties of the membrane that makes it a selective barrier between a cell and it's environment?

Back 27

1.) Double barrier
-prevent hydrophobic molecules from enterind
-prevents hydrophilic molecules from entering

Front 28

What can diffuse or enter the P bilayer?

Back 28

Small hydroPHOBIC compounds

Front 29

What type of compunds can diffuse(go through without help passively) through the P lipid bilayer?

Back 29

1.) Gases
2.) uncharged small polar molecules
3.) Water can diffuse

Front 30

What type of compunds cannot diffuse through the P lipid bilayer?

Back 30

1.) IONS -charged molecules
eg- acetate, ammonium, Na+ etc..
2.) Larger Polar Molecules
eg- sugars, (sucrose), amino acids, proteins

Front 31

Why are Ions impermisable to the P bilayer?

Back 31

Penetrate - Differential Diffussion of different compounds through the membrane.

Front 32

What problems are caused by Differential Diffusion?

Back 32

1.) Water can go through but Glucose cannot

Front 33

What does diffusion mean?

Back 33

the unimpaired movement of soluble materials from one area to another until and equilibrium is reached.

Front 34

Make up question

Back 34

the diffusion of one solute does not impact onthe difusion of other solutes

Front 35

What direction does the diffusion take place?

Back 35

Direction of solutes is from an area of hifh concentration to an area of low concentration.

Front 36

What happens to the concentration of the solutes at Equilibrium during diffusion?

Back 36

The concentration of the different solutes will be uniform.

Front 37

What is Osmosis?

Back 37

-Movement of water accross a semi-permiable membrane in response to a difference in solute concentration accros that membrane.

Front 38

What happens to a plant cell that is in a hypotonic solution?

Back 38

1.) water will enter the cell
2.) membrane will expand
3.) Cell wall does not burst
4.) cell pressure increased

Front 39

What is Turgor Pressure?

Back 39

-Pressure bulit up by water entering the plant cell due to the rigid cell wall.

Front 40

Whst is called Plasmolysis?

Back 40

-Plant cell will shrivel up as water is sent out of the cell.

Front 41

What is a Hypotonic cell?

Back 41

Cell that has released it's water and shriveled up

Front 42

What is a Hypertonic Cell?

Back 42

Cell that has absorbed water and has expanded. Animal cells will possibly burst.

Front 43

What is passive diffusion or passive transport?

Back 43

moving biochemicals and atomic or molecular substances across the cell membrane.NO ENERGY is involved

Front 44

What is Osmosis?

Back 44

Osmosis is the diffusion of water molecules across a selectively permeable membrane.

Front 45

How is osmosis a potential force?

Back 45

due to the movement of water in a closed unit

Front 46

What is the impact of osmosis on an animal cell in a hypotonic solution?

Back 46

the cell will shrivel

Front 47

What are the 4 kinds of Passive transport/diffusion?

Back 47

diffusion, facilitated diffusion, filtration and osmosis.

Front 48

What is the impact of osmosis on an animal cell in a hypertonic solution?

Back 48

The cell will burst

Front 49

What is Osmolarity?

Back 49

Osmolarity is a measure of the osmoles of solute per liter of solution. it is the concentration of all solutes

Front 50

What happens to the plant cell if the osmolarity inside the cell is greater than outside?

Back 50

Turgor pressure is increased.

Front 51

What does it mean when a cell interior and exterior are ISOTONIC or ISOOSMOTIC?

Back 51

the [] of the solute is the same on the inside and outside of the cell.

Front 52

When can hypotonic and hypertonic be used as terms?

Back 52

They are comparative terms. When one side is Hyo the other must be hyper.

Front 53

What is the first major functions of protein on the membrane?

Back 53

1.) transport of solutes (that cannot diffuse)in/out of cell

Front 54

What is the second major functions of protein on the membrane?

Back 54

Catalytic - membrane proteins are enzymes

Front 55

What is the third major functions of protein on the membrane?

Back 55

Signal Transduction -informs the inside of the cell what's going on outside

Front 56

What is the 4TH major functions of protein on the membrane?

Back 56

Proteins as receptors and cell-cell adhesion

Front 57

What is the fifth major functions of protein on the membrane?

Back 57

attachement of the membrane to the cytoplasm

Front 58

What strategies relative to transport accros the membrane do proteins employ?

Back 58

1.) Uniporters
2.) Symporters
3.) Antiporters

Front 59

What's a uniporter?

Back 59

-selectively carry ONE type of molecule into the membrane

Front 60

What's a symporter?

Back 60

-selectively carry TWO types of molecules
-carry them always in the same direction

Front 61

What's an antiporter?

Back 61

-selectively carry TWO types of molecules
-Carry them in opposite directions

Front 62

What are the 2 types of uniporters?

Back 62

Carrier or Channel proteins

Front 63

What's a carrier protein?

Back 63

Uniporter carrier proteins work by binding to one molecule of solute at a time and transporting it with the solute gradient

Front 64

What's a channel protein?

Back 64

Uniporter channels open in response to a stimulus and allow the free flow of specific molecules

Front 65

What's a solute gradient?

Back 65

A series of progressively increasing or decreasing differences in the solute of a cell.

Front 66

What's facilitated diffusion?

Back 66

Diffusion facilitated by proteins , uniporters, symporter & antiporters

Front 67

What type of energy is need for facilitated diffusion?

Back 67

Note that no ATP or ion gradient is involved with facilitated diffusion.

Front 68

What is the major problem with Facilitated Diffusion?

Back 68

at equilibrium, the concentration may not be adequate needed for the cell.

Front 69

How often does a facilitate diffusion go to equilibirum?

Back 69

ALWAYS

Front 70

Explain Passive transport?

Back 70

-Diffusion
-Facilitated Diffusion (proteins)

Front 71

What is Active Transport?

Back 71

Active transport is the process of moving particles with the use of applied energy across biological membrane against the concentration gradient.

Front 72

What are the types of energy needed for active transport?

Back 72

-ATP(from chemical reactions)
-Coupling to another chemical gradient

Front 73

What is a symport system?

Back 73

A mechanism of transport across a membrane in which two different molecules move in the same direction.

Front 74

What is an example of a symport system?

Back 74

Proton pump takes a glucose molecule through the membrane to increase the concentration.

Front 75

What is a proton pump?

Back 75

is an integral membrane protein that is capable of moving protons across the membrane of a cell, mitochondrion, or other subcellular compartment.

Front 76

What does a proton pump generate across the membrane?

Back 76

-a Ph gradient
-an electrical charge inside and outside the membrane
(generating a voltage)

Front 77

How does the Proton pump change the Ph of the cell?

Back 77

Pumps H+ ions in or out of the cell and leaves OH groups behind.

Front 78

What is another name for a proton pump?

Back 78

-Electrogenic Pump

Front 79

What would happen if you had a sodium pump?

Back 79

-NaCl would break the bond and you are left with Na+, Cl-
Electrogenic pump

Front 80

What are the two ways Eukarotic Cells transport bulk material in/out?

Back 80

Endocytosis
Exocytosis
-use of transport vesicles fuse to the cell membrane and dump materials in/out

Front 81

What are the different types of Endocytosis?

Back 81

1.) Solids - Phagocytosis
2.) Liquids/solutes Pinocytosis
3.) Receptor mediated Endocytosis

Front 82

What is Receptor mediated Endocytosis?

Back 82

is a process by which cells internalize molecules (endocytosis) by the inward budding of plasma membrane vesicles containing proteins with receptor sites specific to the molecules being internalized.