4. Cell Transport Across Membrane Pt.1

Question 1

Anion/Cation

Answer 1

Anion: Negatively charged
Cation: Positively charged

Question 2

Hydrophilic

Answer 2

water-loving; having an affinity for water; capable of interacting with water through hydrogen bonding

Question 3

Ion

Answer 3

an atom or group of atoms that carries a positive or negative electric charge as a result of having lost or gained one or more electrons.

Question 4

Inorganic ion

Answer 4

atoms (or groups of atoms) with an electric charge that do not contain carbon.

Question 5

Organic molecule

Answer 5

molecules that are made of carbon and hydrogen, and can include other elements

Question 6

Polar/non polar

Answer 6

Polar: different things at each end; positive and negative ends
Non-Polar: same ends

Question 7

Protein conformational change

Answer 7

• induced by pH variation, temperature, effectors, etc
• shifts in the partition coefficient of the protein

Question 8

Solute/solven/solution/Concentration

Answer 8

Concentration of solution: a measure of the amount of solute that has been dissolved in a given amount of solvent or solution

Question 9

Water -soluble molecules

Answer 9

4-5 carbon atom rule: Molecules with fewer than 4-5 C atoms per hydrogen bonding group will likely be soluble in water. Molecules with more than 4-5 C atoms per hydrogen bonding group will likely be insoluble in water

Question 10

Macromolecules

Answer 10

polymers, long chains of molecular sub-units called monomers

Question 11

Specialized membrane
transport proteins

Answer 11

• Liposomes are impermeable to most water-soluble molecules
• ## cell membranes contain transport proteins

Question 12

What is diffusion?

Answer 12

the movement of molecules in a fluid from areas of high concentration to areas of low concentration

Question 13

Differences in the concentration of inorganic ions across a cell membrane create a membrane potential

Answer 13

• Electrical charges inside and outside are balanaced

Question 14

Voltage Difference

Answer 14

Created by small excesses of positive or negative charge on the two sides of the plasma membrane

Question 15

Membrane potential

Answer 15

voltage difference across the membrane

Question 16

Resting Membrane Potential

Answer 16

Cell rest; the exchange of anions and cations across the membrane is steady

Question 17

Two classes
of membrane proteins

Answer 17

Transporters and Channels

Question 18

Transporters

Answer 18

transfer small organic molecules or inorganic ions

Question 19

Channels

Answer 19

• form tiny hydrophilic pores and allow substances to pass by diffusion
• most channels are ion channels

Question 20

Solutes transport

Answer 20

Passive or Active

Question 21

downhill movement

Answer 21

Molecules flow from a region of high concentration to a region of low
concentration

Question 22

Passive transport

Answer 22

Downhill movement is passive and requires no energy

Question 23

Active transport

Answer 23

uphill movement requires energy

Question 24

Osmosis

Answer 24

the diffusion of water across
membranes

Question 25

Passive transporters

Answer 25

change conformation to mediate transport across the
membrane

Question 26

Active transporters / Pumps

Answer 26

Movement of molecules or ions against their concentration and/or electrical
gradient

Question 27

3 types of proteins for active transport

Answer 27

uniporters, symporters, or antiporters

Question 28

3 types of energy sources are used in active transport

Answer 28

-ATP (used by primary active transporters)
-Electrochemical gradient (used by secondary active transporters)
-Light

Question 29

Coupled transporters

Answer 29

• mediate coupled transport using electrochemical gradients
• secondary active
  transporters

Question 30

3 types of endocytosis

Answer 30

phagocytosis, pinocytosis, and receptor-mediated endocytosis

Question 31

Receptor-mediated endocytosis

Answer 31

Specific uptake of large molecules (LDL uptake)

Question 32

Pinocytosis (Cellular rinking)

Answer 32

cell takes in the fluids along with dissolved small molecules

Question 33

Phagocytosis (cellular eating)

Answer 33

a cellular process for ingesting and eliminating particles larger than 0.5 μm in diameter

Question 34

Exocytosis

Answer 34

secretory vesicles fuse with the plasma membrane and releases (secretes) its content into the extracellular space