Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Foundations of Medicine PA S1 > Intro to Physiology Review > Flashcards

Intro to Physiology Review Flashcards

1
Q

What is physiology?

A

study of the function of body parts
- how all the body parts work and carry out their life-sustinaining activities

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Biological membranes are made up of…

A

a. lipids (phospholipids, cholesterol, and glycolipids)
b. proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Cell Membrane Structure

A

lipids of cell membrane form a phospholipid bilayer with the hydrophobic (water insoluble) ends of each lipid molecule face the interior of the membrane and the hydrophilic (water soluble) ends face outwards

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Integral membrane Proteins

A

they are embedded in the phospholipid bilayer of cell membrane and cannot be removed without disrupting it. They include channels, pumps, carriers and receptors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Peripheral Proteins

A

they bind to the hydrophilic polar heads of the lipids or the integral proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Passive Transport

A

ions being able to fuse across the membrane without any energy expenditure of the cell (ATP use)
1. Diffusion (simple or facilitated)
2. Osmosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Active Transport

A

ions have to be transported with the help of channels that require ATP expenditure to work
1. Primary Active Transport
2. Secondary Active Transport

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Vesicular Traffic & Plasma Membrane

A

travel of things in and out of the cell through membrane bound things
1. endocytosis
2. exocytosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Simple Diffusion

A

net movement of molecules (or ions) from a region of their high concentration to a region of their lower concentration
- occurs through the cell membrane by two pathways:
a. interstices of the lipid bilayer
b. through protein channels
- no interactions with carrier proteins
ex: O2, CO2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

“Gating of Channels”

A

protein channels can be gated and these are regulated by:
a. electrical signals (voltage-gated)
b. chemicals (ligand-gated)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Factors Affecting Rate of Simple Diffusion

A
  1. concentration gradient across membrane
  2. surface area of membrane
  3. solubility in the membrane or permeability (the more soluble the substance, the faster it will diffuse)
  4. thickness of membrane (thicker membrane = slower rate of diffusion)
  5. molecular weight of ion (not directly clinically important)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Facilitated/Carrier Diffusion

A

movement of substances in combination with carrier protein without utilization of energy
- diffusion approches a maximum which is dependent on the saturation of the carrier proteins
- ex: transport of glucose and most amino acids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Osmosis

A

diffusion of water across a semipermeable membrane or selectively permeable membrane
- water will diffuse from a region of higher water concentration to a. region of lower water concentration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Isotonic Medium

A

no movement of fluid from ICF or ECF

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Hypertonic Solution

A

higher concentration of things outside cell and lower concentration of water so water moves out of cell into solution to balance it and therefore shrinking the cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Hypotonic Solution

A

lower concentration of things outside the cell than inside and higher concentration of water outside so fluid moves from ECF to ICF, expanding the cell and in some instances, bursting it

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Active Transport

A

net movement against a concentration gradient and requires energy to do so (ATP)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Primary Active Transport

A

ATP is consumed directly by the transporting protein
- ex: Na/K-ATPase pump, calcium pump

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Secondary Active Transport

A

depends directly on ATP as a source of energy
- in co-transport, molecules move in the same direction
- for ex, movement of Na+ and glucose in renal tubules and gut
- in counter transport, molecules move in opposite direction for example, Na+ and Ca2+ in heart and muscle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Characteristics of All Protein-Mediated Transport

A

a. Rate of Transport: transport faster than it would be by diffusion
b. Saturation Kinetics: transport rate increases directly with the rise of concentration, but once the transporters become saturated, transport rate is maximal
c. Chemical Specificity: substance must have a certain chemical structure that matches with the transporter
d. Competition for Carrier: substance of similar chemical structure may compete for the same transporter

21
Q

Endocytosis

A

the movement of macromolecules from outside the cell to inside the cell by active invagination of plasma membrane

22
Q

Phagocytosis

A

process by which solid bits of material are engulfed by cells (type of endocytosis)

23
Q

Pinocytosis

A

uptake of molecules in the solution

24
Q

Exocytosis

A

process by which macromolecules are packed in secretory vesicles and extruded from the cell
- requires both calcium and energy

25
Q

Constitutive Secretion

A

vesicles are not coated with clathrin and are continuously fusing with the cell membrane and being released
ex: release of proteins such as albumin

26
Q

Regulated Exocytosis

A

vesicles are coated with clathrin, and a signal is required before the vesicle will fuse with the membrane

27
Q

Intracellular Fluid (ICF)

A

fluid inside cells
- takes up approx 2/3 of total body water

28
Q

Extracellular Fluid (ECF)

A

fluid outside/around cells
- takes up approx 1/3 of total body water

29
Q

Interstitial Fluid (ISF)

A

outside cell and in between cells specifically
- approx 2/3 of ECF

30
Q

Vascular Fluid (VF)

A

type of ECF and is a mix of plasma + RBC, flows through veins, capillaries, etc.
- approx 1/3 of ECF

31
Q

ICF Components

A
  • K+
  • Mg
  • PO4
  • Protein
32
Q

ECF Components

A
  • Na+
  • Ca2+
  • Cl2-
  • HCO3-
  • O2, CO2, glucose, fatty acids, amino acids
33
Q

What happens in the case of loss of isotonic fluid?

A

the volume of the ECF and VF is reduced but the osmolarity does NOT change as isotonic fluid was lost and so osmolarity is NOT affected
- since ECF osmolarity is unchanged, there is no change to ICF volume

34
Q

What happens in the case of a loss of Hypotonic fluid (sweating, hypotonic urine)?

A

Loss of hypotonic fluid from ECF makes ECF hypertonic so ICF fluid will move to ECF to balance it out, shrinking the cells

35
Q

What happens if you ingest salt tablets?

A

Salt tablets make ECF hypertonic so fluid goes from ICF to ECF

36
Q

Isotonic Fluid gain will cause:

A

Increase in ECF volume but no change in osmolarity and no effect on ICF osmolarity or volume

37
Q

Hypotonic fluid gain will cause:

A

Increase in ICF osmolarity as ECF becomes hypotonic, so then fluid flows into the ICF, increasing the osmolarity

38
Q

Action Potential

A

a short lasting, reversible change in electrical potential occurring on the surface of an excitable cell, especially of a nerve or a muscle cell, that occurs when it is stimulated, resulting in the transmission of an electrical impulse

39
Q

Resting Membrane Potential

A

-90 mv (in some cells) but USUALLY (-70mv)

40
Q

Depolarization

A

+30mv

41
Q

Threshold Potential

A

USUALLY -55mv

42
Q

Voltage Changes During Action Potential

A

1st step: Depolarization: voltage gated Na channels open and there is influx of Na ions causing the resting membrane (-70mv usually) potential to become more positive
2nd step: Repolarization: voltage gated K channels open and there is efflux of K ions causing the membrane potential to return back to its resting state
- all through cell there are Na+K+ pumps which keep pumping in K and Na out of the cell at a ratio of 2:3

43
Q

Ungated Potassium Channels

A

these channels are always open, and unless the membrane potential reaches the potassium equilibrium potential
- a potassium equilibrium is maintained through these Channels

44
Q

Voltage-Gated Sodium Channel

A

these channels are closed under resting conditions. membrane stimulus/signal causes these channels to quickly open and close and cause the depolarization phase. once they close, they will not respond to a second stimulus until the cell almost completely repolarizes

45
Q

Voltage-Gated Potassium Channels

A

these channels are closed under resting conditions. they require a stimulis/signal to open and are responsible for…slide cuts off

46
Q

Absolute Refractory Period

A

the period during which no matter how strong the stimulus, it cannot induce a second action potential
- this period is due to voltage inactivation of sodium channels

47
Q

Relative Refractory Period

A

that period during which a greater than normal stimulus is required to induce a second action potential

48
Q

Cell Diameter

A

the greater the cell diameter, the greater the conduction velocity

Foundations of Medicine PA S1 (13 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions