Chapter 7 Cell Membrane

Question 1

GLUT

Answer 1

Glucose Transport Protein

Question 2

Sodium Potassium Pump

Answer 2

Protein moves sodium outside cell & potassium inside

Constantly requires ATP –>

1 ATP to move
3 Sodium Ions (smaller)
and
2 Potassium Ions (larger)

All nerves and lots of cells inside our bodies use these pumps to maintain the balance of Sodium on the outside and Potassium on the inside

Question 3

Hypertonic

Answer 3

High concentration inside cell –> low concentration outside

Question 4

Isotonic

Answer 4

State of Equilibrium

Question 5

Hypotonic

Answer 5

High concentration outside cell–> low concentration inside

Question 6

Dynamic Equilibrium

Answer 6

Same concentration with mols flowing into & out of the membrane at the same rate

Question 7

Two types of larger scale active transport

Answer 7

Endocytosis and Exocytosis

Question 8

Endocytosis

Answer 8

Moving cells inside

Occurs in phagocytes
–> cell membrane folds inwards and creates a phagosome

Question 9

Concentration Gradient

Answer 9

Moving down the concentration gradient requires no energy –> molecules naturally move from high concentration to low

moving up the concentration gradient does require energy –> low concentration to high

Question 10

Diffusion

Answer 10

When molecules can dissolve through the lipid bilayer following their concentration gradient

Passive transport

Question 11

Facilitated Diffusion

Answer 11

Molecules are assisted by transport proteins but still move alongside their concentration gradient to pass through a cell membrane

Passive Transport

Question 12

Osmosis

Answer 12

Diffusion of water across a membrane

Question 13

Sodium and Glucose Cotransporter Protein

Answer 13

Both Sodium and Glucose Molecules move into the cell simultaneously through contransporter protein

Sodium moves down it’s concentration gradient (caused by the sodium potassium pump) and glucose moves against its concentration gradient

Another form of ACTIVE transport

Question 14

Aquaporins

Answer 14

also called water channels, are channel proteins used mainly to facilitate transport of water between cells.

Question 15

Membrane components made from something attached to a sugar that help with cell recognition

Answer 15

Glycoproteins + Glycolipids

Question 16

Amphipathic

Answer 16

hydrophilic head
hydrophobic tail

like a frog

Question 17

Cholesterol does what in cold temperatures?

Answer 17

maintains fluidity by preventing tight packing

Question 18

Cholesterol does what at high temperatures

Answer 18

prevents movement of phospholipids

Question 19

2 types of membrane proteins (location-wise)

Answer 19

Peripheral proteins
Integral Proteins (incl. trans membrane proteins)

Question 20

Functions of the Proteins

Answer 20

transport
enzymatic activity 
signal transduction
cell-to-cell recognition
inter cellular joining
attachment to Cytoskeleton and ECM

Question 21

What kind of transport proteins allow for passage of molecules and ions?

Answer 21

Channel proteins

Question 22

What kind of proteins bind to molecules, change shape and take them across?

Answer 22

Carrier Protein

Question 23

Will a Glucose transporter also transport Fructose? (also C6H12O6)

Answer 23

no

Question 24

What happens to the cell membrane in a plasmolyzed plant cells

Answer 24

It will pull away from the cell wall and the H2O previously inside the cell will fill the space. This can be lethal to the cell

Question 25

Ion Channels

Answer 25

gated proteins that open/close in response to stimulus

Question 26

Explain the U tube experiment

Answer 26

u should known this. google it if you don’t

Question 27

What is membrane potential?

Answer 27

Voltage difference across a membrane.

This can be caused by a diff in + and - ions.

Question 28

What two types of force effect membrane potential?

Answer 28

Chemical force & Electrical Force

Question 29

More specific than concentration gradient

Answer 29

Electrochemical Gradient

Question 30

Cotransport

Answer 30

Transport of one solute helps transport of another solute

Question 31

3 types of endocytosis

Answer 31

Phagocytosis
Pinocytosis
Receptor Mediated Endocytosis

Question 32

Phagocytosis

Answer 32

Cell eating (takes in one large mol)

Question 33

Pinocytosis

Answer 33

Cell drinking (takes in extracellular fluid)

Question 34

Receptor Mediated Endocytosis

Answer 34

Help of ligands (receptors) to take in bulk quantities of specific mols

Question 35

Ligands

Answer 35

bind to particular mols and allows for the endocytosis of bulk quantities of specific mols