chp 1 Flashcards
extracellular matrix
Def:
Allows cells to form tissues and organs
Extracellular Matrix
- Macromolecules: (5)
- Collagen
- Elastin
- Fibronectin
- Proteoglycans
- Hyaluronic acid
Extracellular Matrix - Function:(4)
- Mechanical support
- Control of cell proliferation
- Scaffold for tissue regeneration
- Provides a microenvironment for tissues
Basement membrane (basal lamina) Def:
specialized ECM
Basement membrane (basal lamina)/
- describe structure
- location? (2)
- surrounds?(3)
thin, tough, flexible
location: under the epithelial and above the connective tissues, so its between cell sheets.
Surrounds: individual cells
fat, muscle, schwann cells
Cell adhesion Molecules(CAMs)
def:
surface proteins that bind to adjacent cells&ECM.
Cell adhesion Molecules(CAMS) protein families? (4)
integrins
cadherins
selectins
immunoglobulin super fam
CAMs involved in? (4)
- tumorigenesis
- blood-brain barrier establishment
- help lymphocyte find their target.
- inflammation
Cell Adhesion Molecules:
- Inflammation plays a critical role in and how?
3. steps
- early development of atherosclerosis.
- Arteries have endothelial cells that get damaged by High BP.
- Glycosylated CAMs (glucose group) attaches to them.
- Recruit/ bind (wbc) AKA
(inflammation stage of atherosclerosis)
Specialized Cell Junctions:
- Def: holds…. providing….
- (____ proof)
- BIG on_______
- maintain polarity where?
- _________ complex
- holds cells together
- providing strong mechanical attachment
- leak proof
- big on communication
- apico-basal
- junctional complex
Specialized Cell Junctions:
- 3 types? where are they close to/located
- Adherens - close to apex
- Desmos: close to apex
- Hemidesmo: base of cell
Apicobasal polarity
- sections broken in? what is it?
- connections of cell?
- having this allows
- sections broken into 2: apex-top, base-bottom.
- connections of cell coming all together.
- certain functions occur on top and bottom
Specialized cell junctions; allow for special cell communication
ex: how
electrical waves going from cell to cell.
apex:
- where?
- Function
- goes to?
- have what features?(2)
- upper, free surface
- secretion
- goes to lumen
- have microvilla/cillia
basal:
- where?, attached to
- function
- coming from?
- lower, attached to surface
- absorption
- from lumen ( cuz above it is the apex and that TO lumen so basal is FROM lumen)
What helps maintain apico-basal polarity?
specialized Cell junction
Junctional Complex:
- (4) types
- gating:
- chem that helps gating, where is gating located.
desmos,tight,gap,connexons
gating: control permeability(its a gate allows things in/out)
- Ca++ in cytoplasm
Cell communication maintains:
regulates?
coordinates?
homeostasis, regulates growth, division, coordinates functions
Cell communiction:
2 types
control dependent signals
remote signals
Contact dependent signals?
3
paracrine
autocrine
neurotransmitter
Remote signals (2)
Hormonal
Neurohormonal
Contact dependent signals means?
cells close in contact NOT in bloodstream
Remote signals means?
chem signals in bloodstream
Paracrine Signals?
chem messengers target nearby target cells
Autocrine signals
secreting cells targets ITSELF
neurotransmitter signals
- neuron secretes a neurotransmitter
- across synaptic cleft
- to receptor on postsynaptic target cell
hormonal signals
a hormone secrets into bloodstream delivered to target cell
Neurohormonal signals
neuron secrets chem messenger into bloodstream delivered to target cell.
Differentiate between transduction(signals) by channel regulation VS. second messenger cascades
(these are 2 types of signals)
- normal signal:_/received by ?
- cascades:4 steps?
signals create/release a molecule- received by target cells thru receptor proteins.
signal cascades: relay-> amplify->distribute->modulate signal.
if chem messenger is___ its cant cross?
Therefore, it binds to ____
when it responds we 2 thing?
polar
non-polar lipid bilayer
1. channel reg
2. 2nd messenger
Channel regulation:
def?
ex: motor nerve is? releasing?
open/close of ion channel
- motor nerve is DEPOLARIZED, releases acetylcholine.
Channel regulation:
Talk about acetylcholine steps?
- Acetylcholine binds to Cholinergic receptors
- opens Na+ channels
for sarcolemma
2nd messenger
- example for how to get a tissue response?
catecholamines bind to
AR for tissues responses.
2nd messenger
- 2 pathways
- cAMP: epineph binds to betaAR, activates cAMP
2. Ca++: norepineph binds to alphaAR, activates Ca++
growth factors that transmit signals within and between cell
cytokines
Metabolism:
1.
2.
Chemicals maintaining cell functions
Provides cells with energy
Anabolism:
def?
ex:?
- energy using
- Gluconeogenesis
Gluconeogenesis?
Forms glucose from?(4)
pyruvate, lactate, glycerol, aminos
Catabolism:
def:
ex:
- energy releasing
- Glycolysis
Glycolysis:
breakdown of glucose to?
pyruvate, lactate
ATP useful work in human body.
- Like where does it come from?
- Therefore is used in
- ATP comes from organic molecules(carbohydrates, lipids, and proteins) (food that we eat)…which are CATABOLIZED, and transferred to ATP.
Used in: Organic mols, muscles contraction, active transport.
The food we eat isnt what gives us energy its when it is
catabolized
Atp functions:(2)
- stores energy
2. transfers energy
ATP transfers energy
from ___ to _____
ex:
chemical to mechanical
ex: skeletal muscle contration
Foos production of cellular energy (3 phases)
Phase 1: Digestion
Phase 2: Glycolysis
Phase 3: Oxidative phosphorylation
digestion phase 1
Proteins -> aminos
carbs/poly-> simple sugar
Fats-> fatty acids
glycolysis (phase2)
Macro nutrients into 2 carb molecules aka Acetyl CoA.
Metabolism of glucose to pyruvate(slow) or lactate(fast)
Produces NADH and 2 net ATP
Glycolysis Phase 2:
location:
Metabolism of glucose to (2)
Produces:
in: cytoplasm
Glucose to: pyruvate(slow) or lactate (fast)
produces: NADH & 2 ATPs
Oxi phosphorylation (phase 3) This point of this??
ATP generated
Oxi phosphorylation: In: Mechanism: 1. def: - - - -
in: mito
1. (reduced electron carriers re-oxidized)
- NADH -> NAD+
- FADH2 -> FAD+
- O2 -> to water
- temp H+ generated, powers ATP from ADP.
Acetyl CoA is known as the
final entry point into the kreb cycle ( bc food gets super chopped up and leads to Acetyl CoA)
Kreb cycle is call this bc
2 C’s enter Acetyl CoA and
2 C’s exist as CO2
Passive Membrane:
occurs when?
3 types?
lipophillic molecules (o2,co2, steriods), water & solutes flow thru pores and dwn concentration.
-Diffusion, filtration, osmosis
Diffusion:
depends primarily on:
rate depends on:
PRIMARILY dependent on concentration gradient.
- Rate depends on surface its at, concentration of gradient, thickness of memb
Larger membrane surface area =
Higher rates of diffusion
Greater concentration gradients =
HIGHER diffusion rates
Thicker membranes =
LOWER diffusion rates
Osmosis =
1.
2. pressure
3. pressure
- Water moving towards where there is MORE solutes.
- Osmotic pressure opposes hydrostatic pressure.
- Oncotic/colloid pressure overall osmotic pressure caused by proteins that dont go through.
Filtration
-pressure
-
- ex?
- hydrostatic pressure
- Water/solutes move due to a PUSH from on side of membrane.
ex: blood vessels - push by gravity and pumping heart
where is more hydro pressure
side with more water.
Active transport:
requires life,
Na+/K+ pump against gradient
Na+/K+ Pump =
describe its flow
- Does ____ work?
- if this didn’t exist what would happen?
- 3 Na+ OUT, 2 K+ IN(antiport system)
- Does osmotic work, every ATP -> 3na out, 2k in. NET LOSS of SOLUTE cuz 3 is leaving only 2 coming in. SO WATER follows, so cells have constant water.
If NA+/K+ pump did not exist cells would swell because we wouldn’t have the net loss of solute allowing water to follow.
Vesical transport: (3)
- endocytosis (taking in)
- exocytosis (releasing)
- transcytosis (taking in and releasing)
Resting Membrane Potential:
- difference in?
- NA+, K+ pump maintains concentrations cuz?
- voltage in membrane
- Na+ more concentration out of cell cuz they go out
- K+ more concentration in of cell cuz they go in
- So there’s a balance
- Na+ more concentration out of cell cuz they go out
Resting membrane is leakier for na+ or k+
K+ bc it diffuses out easily vs. Na+
Result of resting membrane and thats not the na+/k+ process?
excess anions inside membrane, and increase in cations outside the cell -> difference in charge distribution=polarized -> resting potential is NEGATIVE.
because K+ is positive and its leaving and the negatives aren’t, there is no way for them too, they just stay in while this whole na+/k+ pump is going on. THIS IS WHY RESTING IS NEGATIVE…negatives are resting inside the membrane there is no way for them to leave. POSITIVE IS ALL OUTSIDE. THIS DIFFERENCE IS the nature of RESTING MEMBRANE POTENTIAL
Electrolytes:
Non-electrolytes:
cation+,anions- (dissociates)
Glucose, urea, creatinine (doesn’t dissociates)
Action potential:
- Resting cell->activated by electrochemical stimulus->Na+ gates OPEN, rushing in so many that DEPOLARIZES (removes) threshold -> cells continue depolarizing w/o stimulation, usually it needs stimulation but since its surpassed its threshold its going crazy.
* 2. RAPID reversal in polarity; the inside that was alll neg and chilling will become positive.= action potential - Repolarizes(reverse the starting step), cant be neg out and pos in the rush has to stop.
- NEGATIVE MEMBRANE POTENTIAL COMES BACK(neg in,pos out-na+/k+ pump)
- Na+ gates close,K+ open = memb is neg now
- Resting memb is back to normal (resting - are back inside)
Depolarization:
the rushing in of Na+
Repolarization:
Neg memb potentional jumps in to reverse the crazy na+. Na/k pump comes back too.
Resting:
Na/k pump…anions in membrane
Cell Cycle =
- repeated duplication/division
- interphase (G1, S, G2phase)
- M Phse = Mitosis
Describe;
G1,S,G2 &
M Phase/cytokinesis
-4 types of M phase
G1 phase - gap (presynthesis)
S phase - DNA replication and synthesis
G2 phase - RNA and protein synthesis (premitotic)
M phase - mitosis (splitting of nuclei) and cytokinesis (splitting of cytoplasm); shortest phase Prophase Metaphase Anaphase Telophase
the cell cycle control system ?
Different rates of cellular division:
Completed cycle takes 12-24 hours
Interphase = LONGEST
M phase = shortest
Mitogens:
- induce?
- 3 examples
- Induce mitosis
2. EX: PDGF can stimulate smooth muscle cells, neuroglial cells, and fibroblasts to divide
Growth factors:
Def:
ex: (2)
Stimulate cell growth by promoting protein synthesis
ex:
1. insulin-like growth factors 1 and 2
2. Transforming growth factor 𝜷
Survival factors
Promote survival by suppressing apoptosis(programmed cell death)
Cells are constantly turning over, Worn out cells under go
cell death and get replaced by
replication and division process to always have working viable cells.
