Cell Physiology Flashcards
1
Q
physiology
A
study of how living organisms function
2
Q
integration
A
- how the systems of the body parts work together
- how each work towards function of a whole
- how they influence each other
3
Q
homeostasis
A
the maintenance of a relative stable internal environment; central theme in physiology
4
Q
variables maintained by homeostasis
A
- nutrient molecules (glucose)
- O2 and CO2
- waste products
- water/electrolytes
- pH (acidity)
- temperature
- blood pressure
5
Q
loss of homeostasis
A
caused by illness or lead to illness
6
Q
homeostatic control systems
A
- negative feedback
- positive feedback
- feedforward regulation
7
Q
negative feedback
A
the primary mechanism by which body systems maintain homeostasis
8
Q
set point temperature
A
37 degrees C
9
Q
set points
A
can be reset in special cases
- elevated body temperature
- exercise and blood pressure
10
Q
positive feedback
A
to produce rapid change / acceleration of a process
11
Q
feedforward region
A
anticipates change in regulated variables and improves the body’s homeostatic responses to minimize deviation from the set point
12
Q
extracellular fluid
A
- plasma
- interstitial fluid
13
Q
intracellular fluid
A
mostly water inside cells
14
Q
cells
A
structural and functional units of the body & the smallest unit of life
15
Q
basic cell components
A
- nucleus
- cytoplasm
- plasma membrane
16
Q
nucleus
A
contains DNA
17
Q
cytoplasm
A
organelle and cytosol
18
Q
plasma membrane
A
the gatekeeper of the cell / controls what goes in and out
- selectively permeable
19
Q
plasma membrane physical / chemical properties
A
- hydrophobic
- lipophilic
- electrical potential
20
Q
plasma membrane proteins
A
- for movement of molecules
- signaling
21
Q
lipid bilayer
A
a double layer of lipid molecules containing embedded proteins and carbohydrates
22
Q
lipid bilayer components
A
- lipids
- proteins
- carbohydrates
23
Q
lipids
A
phospholipids and cholesterol
24
Q
proteins
A
integral and peripheral
25
carbohydrates
attached to lipid (glycolipid) or to protein (glycoprotein)
26
phospholipids
amphiphathic
27
hydrophilic
- polar
- dissolves in water
- ECF
28
hydrophobic
- non polar
- doesn't dissolve in water
- ICF
29
cholesterol membrane functions
- modulates membrane fluidity (increase cholesterol = more fluid)
- endocytosis
- intracellular signaling
30
peripheral
- on membrane surface
- -- do not go in lipid bilayer
- often attached to integral proteins
- signal transduction / enzymes
31
integral
- span membrane
| - hydrophilic / hydrophobic parts
32
types of integral membrane proteins
- receptors
- channels
- cell adhesions
- cell identity
33
glyoproteins
most integral proteins
34
glyolipids
10% of membrane lipids
35
glycocalyx
carbohydrate "coat" on outer surface of cell membrane
36
glyocalyx function
- create negatively charged surface
- cell-cell interactions
- receptors
- immune response
37
plasma membrane permeable to
- water and lipid soluble substances (ethanol, fatty acids, steroids)
- gasses (O2, CO2)
38
plasma membrane impermeable to
- large molecules (glucose, amino acids)
- charged (Na+, K+, etc.) molecules
- -> need carrier or vesicle to enter/exit
39
passive transport
- filtration
- diffusion
- facilitated diffusion
- osmosis
40
active (energy required)
- active transport
| - endocytosis/exocytosis
41
filtration
occurs between cells and is based on differences in hydrostatic pressure
- moves water/molecules between compartments
42
hydrostatic pressure
fluid pressure -- "pushing pressure"
- always flows from high pressure to low pressure
- required to stop osmosis
- equal with osmotic pressure at equilibrium
43
simple diffusion
- based on differences in concentration
- molecules move from high concentration to low concentration until equilibrium
- smaller molecules move faster
- occurs by random molecular motion
- energy comes from heat
44
net flux
net rate of material of transfer from one location to another = always greater from areas of higher concentration to areas of low concentration
45
facilitated diffusion
rate is limited by rate of conformational change of protein carrier
46
osmosis
net movement of water across a membrane from low solute concentration to high solute concentration
47
osmolarity
total solute concentration in solution
| - includes ALL solutes (penetrating and non-penetrating)
48
osmotic pressure
- "pulling pressure"
- more solute means more water wants to flow
- will be equal to hydrostatic pressure at equilibrium
49
tonicity
ability of a solution to affect water movement and cell volume
- includes ONLY non-penetrating solutes
50
hypertonic solution
- cells shrink (crenation)
- waters flows out
- decrease cell volume
51
isotonic solution
- no change in cell volume
| - no net movement
52
hypotonic solution
- cell swells (lysis)
- water flows in
- increase cell volume
53
penetrating solutes
- hydrophobic
- urea
- glycerol
- ethanol
54
non penetrating solutes
- hydrophilic
- ions
- glucose
55
active transport
- against concentration gradient
- requires ATP
- requires membrane proteins
- selective
- transport maximum
- --> can become saturated
56
active transport types
- primary active transport
| - secondary active transport
57
primary active transport
- energy derived directly from ATP
| - ex: Na+ / K+ ATPase (3 Na+ out / 2 K+ in)
58
secondary active transport
- uses energy from concentration differences generated by primary active transport (almost always)
- ex: Na+ / glucose cotransporter
59
endocytosis/exocytosis
- require ATP and many membrane proteins
| - bulk movement of large molecules (proteins / bacteria)
60
endocytosis
digestion of bacteria
61
exocytosis
hormone / neurotransmitters released
62
endocytosis types
- pinocytosis
- phagocytosis
- receptor-mediated endocytosis
- transcytosis
63
pinocytosis
cell drinking
64
phagocytosis
immune cells
65
receptor mediated endocytosis
uptake of cholesterol and cell signaling
66
transcytosis
movement throughout the cell
67
ion channels
from 'pore' for ions to flow through membrane
- highly selective
- saturating (max flow)
68
cystic fibrosis
Cl- channel found in the lungs, pancreas, sweat glands, reproductive tract
- allows Cl- to flow out of epithelial cells into lumen
69
types of ion channels
- "leak channels"
| - gated channels
70
leak channels
always open
71
gated channels
open/closed, under certain circumstances (key)
72
types of gated channels
- voltage gated
- ligand gated
- mechanically gated
73
voltage gated
open/close with change in voltage
74
ligand gated
opened by chemical (hormone, neurotransmitters, growth factor)
75
mechanically gated
physical force pulls channel open
| - stretch, vibration, touch (sensory)
76
dendrites
receive information
77
cell body
process information
78
axon hillock
action potential begins
79
axon
action potential travels down (propagation)
80
axon terminal
neurotransmitters release
81
gated channels in dendrites
- leak
- ligand gated
- mechanically gated
82
gated channels in cell body
- lead
| - ligand gated
83
gated channels in axon hillock
- high voltage gated Na+
| - high voltage gated K+
84
gated channels in axon
- voltage gated Na+
| - voltage gated K+
85
gated channels in axon terminals
- voltage gated Na+
- voltage gated K+
- voltage gated Cl-
