Exam 3 - Lecture 33 (Fluid Interaction)

Question 1

What is concentration?

Answer 1

Amount of a specific substance (solute) in a unit amount of another substance (solvent).

Question 2

What is a solute?

Answer 2

Thing that changes physical appearance in a solution.

Question 3

What is a solvent?

Answer 3

Thing that stays the same in a solution.

Question 4

What are 3 ways in which concentration can be expressed?

Answer 4

1. %
2. Molarity/molality
3. Electrochemical equivalence

Question 5

What are the units for %?

Answer 5

parts/100

Question 6

What is the unit for molarity?

Answer 6

moles/L, kg, M

Question 7

What are the units for electrochemical equivalence?

Answer 7

Eq/L

Question 8

How many molecules are in 1 mole?

Answer 8

6 x 10^23

Question 9

What is the concentration of physiological saline as a %? Molarity? Electrochem. equivalence?

Answer 9

% = 0.9% NaCl sln
Molarity = 150 mM
Electrochem. eq. = 300 mEq/L

Question 10

Concentration gradients are critical in driving _____ across _____.

Answer 10

particle movement; biological membranes

Question 11

What is the structure of a phospholipid?

Answer 11

Hydrophilic head with a hydrophobic (fatty acid) tail

Question 12

What 2 things CAN’T cross the phospholipid membrane?

Answer 12

1. Charged particles

2. Polar molecules

Question 13

What 2 things CAN cross the phospholipid membrane?

Answer 13

1. Lipid soluble molecules

2. Small polar molecules (water)

Question 14

How many passive and active mechanisms are there for movement of things across biological membranes?

Answer 14

2 passive and 2 active

Question 15

What is diffusion and what type of mechanism does it employ?

Answer 15

Movement of particles from [high] to [low];

passive (no energy req.)

Question 16

Rate of diffusion depends on _____ and _____.

Answer 16

size of gradient; permeability of membrane

Question 17

How does gradient and temperature affect diffusion?

Answer 17

Higher gradient/temp = higher difffusion

Lower gradient/temp = less diffusion

Question 18

What is facilitated diffusion and what type of mechanism does it employ?

Answer 18

Movement of particles from [high] to [low] with the help of pores, channels, or carrier proteins;
passive (no energy req.)

Question 19

What types of molecules utilize facilitated diffusion?

Answer 19

charged molecules

Question 20

If particles are charged they can move down an _____ gradient.

Answer 20

electrical

Question 21

Concentration gradient + electrical gradient = _____?

Answer 21

electrochemical gradient

Question 22

What two things make up the electrochemical gradient?

Answer 22

[ ] gradient + electrical gradient

Question 23

Charged molecules want to move _____ their electrochemical gradients through _____.

Answer 23

down; pores

Question 24

What is active transport and what type of mechanism does it employ?

Answer 24

Movement of particles from [low] to [high] against the electrochem. gradient;
Active (req.energy) - hydrolyzes ATP –> ADP

Question 25

How is energy generated in active transport?

Answer 25

ATP –> ADP

Question 26

What does ATP –> ADP do to conformation?

Answer 26

changes it

Question 27

What is secondary active transport and what mechanism does it employ?

Answer 27

Movement of molecules across a biological membrane against gradient;
Active (req. energy) but gets it from other ATP-producing processes in the cell

Question 28

What is another name for secondary active transport?

Answer 28

co-transport

Question 29

How is energy generated in secondary active transport/co-transport?

Answer 29

Potential energy created by active transport elsewhere (NOT ATP hydrolysis)

Question 30

What is an example of secondary active transport?

Answer 30

Glucose movement in the kidney

Question 31

What is a symporter?

Answer 31

Co-transport in the SAME direction

Question 32

What is a antiporter?

Answer 32

Co-transport in OPPOSITE directions

Question 33

What is osmosis?

Answer 33

Movement of water across a selectively permeable membrane from dilute to concentrated solution.
(high [water] –> low [water])
(low osmolarity –> high osmolarity)

Question 34

What does it mean if a sln is dilute?

Answer 34

High [H2O]

Question 35

What does it mean if a sln is concentrated?

Answer 35

Low [H2O]

Question 36

What is an effective osmole?

Answer 36

Molecule (ex: glucose) that cannot cross a membrane and so it generates osmosis.

Question 37

What is osmolarity/osmolality and what are its units?

Answer 37

[ ] of osmotically active atoms; osmoles/L, kg

Question 38

Rank the following from low to high osmolarity: plasma/skim milk, urine, tap H2O

Answer 38

Tap H2O, plasma/skim milk, urine

Question 39

A dilute solution has _____ osmolarity.

Answer 39

low

Question 40

During osmosis, water moves from _____ osmolarity to _____ osmolarity.

Answer 40

low; high

Question 41

What is tonicity?

Answer 41

Overall [ ] of effective osmoles in a sln; [ ] of things that actually cause osmosis.

Question 42

What is an osmole?

Answer 42

Something that generates osmotic pressure.

Question 43

What are the 3 types of tonicity?

Answer 43

1. Hypotonic
2. Hypertonic
3. Isotonic

Question 44

What is a hypotonic solution?

Answer 44

Sln with lower effective osmolarity than another

EX: RBCs swell in hypotonic fluid bc H2O enters the cell

Question 45

What is a hypertonic solution?

Answer 45

Sln with higher effective osmolarity than another.

EX: RBCs shrink in a hypertonic soln bc H2O leaves the cell

Question 46

What is an isotonic solution?

Answer 46

Sln with same effective osmolarity as another.