Physiology Lectures 1-5

Front 1

What is Physiology?

Back 1

Maintaining or moving to a control set point.

Front 2

Molecules

Back 2

Assembly of atoms major physiological ones are proteins, carbs, lipids, and nucleic acids

Front 3

Cells

Back 3

Basic Units of life, uses energy has metabolism, removes waste

Front 4

Tissues

Back 4

Collection of similar cells with same local function, term also used as "Lung Tissue"

Front 5

Organs

Back 5

Collection of different tissues carries out distinct function in the body

Front 6

Systems

Back 6

Collection of organs controls major coordinated functions, respiratio, circulation etc..

Front 7

Homeostasis

Back 7

Maintaining the normal physiological state.

Front 8

Internal Environment

Back 8

Interstitial fluid (liquid around cells)

Front 9

Negative Feedback

Back 9

Common--Event X causes a change away from state set. pt. response y causes a return to set pt.
Basis of homeostasis: Ex: blood pressure, Ion concentrations, muscle reflexes

Front 10

Positive Feedback

Back 10

Rare but important, event x causes set. pt. (state change) no return to original set pt. example: blood clotting, pregnancy

Front 11

Cytosol

Back 11

Liquid between nucleus and membrane liquid portion--high protein content, protein clusters, organized enzyme pathways enhance metabolism

Front 12

Metabolism

Back 12

Thousands of reaction enzymes are protein catalysts structural proteins, energy production, enzymes, storage and use of carbs and lipids

Front 13

Ribosomes

Back 13

Combination of protein and RNA, free ribsomes make proteins for use in cytosol, few or no modifications after production chaperones help protein folding..(proteins manufactured here)

Front 14

Storage

Back 14

Glycogen is polymer of glucose in muscle for use during contraction. In liver to maintain blood glucose between. heart prefers fat, can convert fat into glucose. Brain only uses glucose.

Front 15

Endoplasmic Reticulum

Back 15

Fluid-filled membranous system distributed extensively throughout the cytosol...cytoplasm is outside nucleus inside membrane.

Front 16

Rough ER

Back 16

proteins are manufactuerd here then sent to the smooth ER, projects outward from smooth ER as stacks of relatively flattened sacs.

Front 17

Smooth ER

Back 17

is a meshwork of tiny interconnected tubules. produce vesicles and makes membrane transport vesicles, carry new protein to Golgi Apparatus

Front 18

Golgi Apparatus

Back 18

Amino acids can be changed sugar can be added on once modified, ready for export, secretory vesicles exports

Front 19

Exocytosis

Back 19

(Calcium Triggers)
docking proteins fit into specific places to go where they need to go. Most proteins mold naturally into proper shape. 10,000 X's more calcium inside cell than outside.

Front 20

Protein Modification

Back 20

amino acids can be changed sugar can be added on once modified, ready for export--secretory vesicles export.

Front 21

Exocytosis

Back 21

(Calcium Triggers) most proteins mold naturally into porper shape 10,000 X more calcium inside cell than outside. docking markers, proteins fit into specific places to go where they need to go.

Front 22

Lysosomes

Back 22

(digestive enzymes) membrane enclosed sacs containing powerful hydrolytic enzymes, which catalyze hydrolysis reactions. Digestive Tract chops up in minimal pieces.

Front 23

Endocytosis

Back 23

giving membrane back, phagocytosis (garbage men) white blodd cell surrounds another cell..gets rid of dead cells and bacteria. PUS eww

Front 24

Peroxisomes

Back 24

hundreds of different enzymes O2, oxidation--different from lysosomes helps detoxify the body, oxygen radicals destroy proteins helps get rid of harmful toxic compounds that enter a cell.TP

Front 25

ATP

Back 25

Adenosine triphosphate, this is the form of energy the body can use.

Front 26

Anaerobic Energy Production--Glycolysis

Back 26

During Glycolysis some of the energy from the broken chemical bonds recycles NadH to Nad (they tranfer H onto pyruvic to make lactate) Splits Glucose molecule apart
2 molecules of ATP per glucose molecule
Not enough to support the body

Front 27

Mitochondria- Aerobic Energy Production

Back 27

2 layers of membrane inner membrane contains Krebs cycle, matrix TCA cycle recycles more NadH

Front 28

Citric Acid Cycle

Back 28

Consists of a cyclical series of eight seperate biochemical reactions that are directed by the enzymes of the mitochondrial matrix.

Front 29

Mitochondrial Inner Membrane

Back 29

TCA cycle
Krebs
Citric Acid Cycle.

Front 30

Vaults

Back 30

three times as large as ribosomes are shaped like octagonal barrels, serve as cellular turcks for transport from nucleus to cytoplasm

Front 31

Cytoskeleton

Back 31

the complex protein network portion of the cytosol that acts as bone and muscle of the cells.

Front 32

Microtubules

Back 32

largest of the cytoskeleton, long, hollow tubes, formed by two slightly different variants of globular--shaped tubulin molecules. maintain asymmetric cell shapes and coordinate complex cell movement.

Front 33

Cilia--Flagella

Back 33

numerous tiny hairlike protrusions, flagella--single long, whiplike appendage
cilia- keeps particles out of airway.

Front 34

Immediate Filaments

Back 34

irregular threadlike proteins, help resist mechanical stress.

Front 35

Microfilaments

Back 35

Intertwined helical chains of actin molecules; microfilaments composed of myosinmolecules also present in muscle cells play a vital role in various cell contractile systems; serve as a mechanical stiffener for microvilli.

Front 36

Membrane Structure

Back 36

Seperates ICF from IF physical T chemical barrier

Front 37

Phospholipids

Back 37

Backbone of membranes, soap like
fluidity within membrane and as a whole.

Front 38

Hydrophobic/Hydrophilic

Back 38

Hydrophobic- hard to get to membrane fat soluble membrane
Philic outersides H-phils done cross by diffusion except H2O, higher water sol.

Front 39

Cholesterol

Back 39

Between lipids, prevents close packing of fatty acids chains, creates fluidity--LDLP--Storage (bad), helps carry fats for consumption (good)...prevents membrane from rupturing.

Front 40

Proteins

Back 40

mobile or restricted (most)

Front 41

Channels

Back 41

ions, protein channels span membrane
open?closed
(4) *specialized by ion type--K+, Na+, Ca++, Cl-...receptors open channels

Front 42

Enzymes

Back 42

catalyze--A--B
some always active, some need receptors. can ship foreign DNA

Front 43

Receptors

Back 43

bind to solute--either chemical or ion
some act by physical change
binds to an agonist
connecto to channel or enzyme?
Epinephrine: (adrenaline)- opens up Ca++ channel constricts blood vessels.

Front 44

Docking--Marker Acceptors

Back 44

Recognized bind to secretory vesicles, site of exocytosis

Front 45

Carriers

Back 45

(Revolving) proteins, no Tpase
Alternate open side
1) molecules move w/gradient
2) co-transport w/ion usually Na+
use ion gradient for ESource

Front 46

Cell Adhesions Molecules

Back 46

Anchor cells to others or basal lamina
Maintain tissue integrity

Front 47

Carbohydrate--Protein Complexes

Back 47

Type 1 DIa, auto immune
ID Self
Basis for seperation of cells into tissue during embryonic dev. limit normal tissue growth
abnormalities- metastatic cancer.

Front 48

Intercellular Connections

Back 48

Proteins + large, 4 types of connections

Front 49

CAMs- Cell Adhesion Molecules

Back 49

Proteins
Anchor Cells
Control Cell Migration

Front 50

Tight Junctions

Back 50

*plastic ring of 6 pack, blcok movement between cells, creates tissue sidedness
skin (burns destroy tight junctions, lose fluid) intestines, kidneys
selective transport molecules
must go through cells
retains water

Front 51

Desmosomes

Back 51

cellular rivets
hold moving cells together, especially under stress
*Skin, heart

Front 52

Gap Junctions

Back 52

channels, ion pass, electrical link
passes along elec. signal to activate cell
* Heart, GI, Bladder, Uterus
* Causes simultaneous activation of a tissue.

Front 53

Diffusion across membranes

Back 53

Diriven by electrical or chemical gradients
Simple diffusion, channels and carriers
Diffusion goes in all directions-(Net diffusion)
Will always go HIGH TO LOW

Front 54

Hydrophobicity

Back 54

Fat gases cross easily, fluidity allows 8 micron RBCs to deform through 7 micron capillaries, enhances O2 transport
Membrane is plastered ,
*Heart Pumps entire supply once/min

Front 55

Size

Back 55

O2 is small
H2O can squeeze between phospholipids
*Proteins can never get through

Front 56

Fick's Law of Diffusion

Back 56

Refer to Study Book

Front 57

Ion Channels

Back 57

Na+, K+, Ca++, Cl-
can move by elec + chem gradients
-Refer to study book for pics

Front 58

When you break blood vessels, protein leaks out to surrounding tissues, and cause swelling

Back 58

FUN FACT

Front 59

Osmosis

Back 59

H2O moves from (low solute) to low (high sol.)
semi permeable membranes allow water to cross but NOTHING else.
*Water is drawn out of your blood by others surrounding fluids.

Front 60

Carrier Transport

Back 60

Protein Molecules can change shape in membrane and move across molecules
E for transport and may come from conc. gradient or from ATP.
* Loss of 2% of H2O =loss of 40% of muscle ability, * Glucose is 1/3 of # of carriers.

Front 61

Specificity

Back 61

each carrier transports a specific molecule or type of molecule
some are more specific than others

Front 62

Saturation

Back 62

limited number of carriers in each cell
when all carriers are being used, the rate is a max, Tm Limits mediated transport

Front 63

Facilitated Diffusion

Back 63

No ATP--move down diff grad.
molecules bind to on eside, carriers reorients, molecules leave on other side more binding on high conc. side
high--low

Front 64

Active Transport

Back 64

use ATP to move ions against conc. grad. "ion pump"
*low to high
AT produces ion grad. Across cell membranes

Front 65

Na-K AT Pase

Back 65

Na+ out, K+ in
creates gradients that allow elec signaling
orabain blocks the Na-K AT Pase
IN EVERY CELL ON EARTH

Front 66

Secondary Active Transport

Back 66

doesn't use ATD directly,
2 binding sites=agonist, Na+
E of Na+ grad. (out to in) drives SAT
(o transport) (agonistin) or counter transport (agonist out)
Na+ transports some glucose + aas
in some tissues, other ions drives SAT

Front 67

Membrane Potential- L6
Voltage

Back 67

Seperation of change
cells have - charge inside compared to outer IT fluid
opposite charges line up along membrane

Front 68

Resting Membrane Potential

Back 68

MPis (MV)
Voltage across membrane when cell is not activated
determined by open ion channels
K+ for rest (open channels)--most
some Na+ (few open)

Front 69

Concentration

Back 69

(Na+ lower on inside, K+ Higher on inside)
Diff in K+ + Na+ determines size of membrane potential, proteins balance the K+ chargesw on inside of move K+ than Na+ movement diff in intercellular contribue to diff rest. mem. pot.

Front 70

Permeability

Back 70

Determined by number of open channels
number of open channels Ka+/Na+- determines ion diffusion

Front 71

Na-K AT Pase

Back 71

* Ions are always returned to ATPase
(enzyme)
creates gradients and restores them after ions diffuse across the membrane. Ion pump activity

Front 72

Equilibrium Potential

Back 72

Limits on K+/Na+
What voltage balances chemical Gradient?
Only open channels deternine MP.
+60NA+all-------(-70)(most K+, few Na+)-------(-90 K+ all)
RESTING NEURON MEMBRANE POTENTIAL (-70)
NO CELL ACTUALLY REACHES -90/+60 (only limits)

Front 73

K+ Diffusion at Rest

Back 73

K+ channels are open, K+ diff out
Intracellular protein, A- is trapped in cell
Na+ channels are mostly closed, little diffusion
Ions are constantly diffusing
Negative proteins on inside draw some K+ back

Front 74

Pump/Leak Balance

Back 74

Balance b/t pump + diff (channel) activity since ions constantly diffuse down their gradient a constant input of ATP is needed to maintain gradient.
IONS ARE CONSTANTLY DIFFUSING.

Front 75

Resting MP Changes

Back 75

Membrane potential will change in many cells (nerve, muscle)
MP neg @ rest
MP magnitude decreases (goes toward 0) during depolarization
MP increases (gets more negative) during HYPERPOLAR.
Changes of MP are important

Front 76

MP Changes: Depolarization

Back 76

(towards positive)
MP gets less negative
caused by K+ closing, Na+ opening
MP moves toward Na+ Equilibruim pot.

Front 77

MP Changes: Hyperpolarization

Back 77

MP Gets more neg (towards neg)
K+ opening, Na+ closing
MP moves toward K+ equil pot.
* + 20 IS MOST, -85 IS MOST

Front 78

Graded Potentials

Back 78

Triggered by agonists or by physical force
"water in pond"
* SIZE IS PROPORTIONAL TO SIZE OF STIMULUS
spread to adjacent areas, but decays rapidly over time/distance
causes membrane to be more positive
receptors, neurons, muscles
neurons/muscles> need threshold of A.P.
Refer to book for picture

Front 79

L7- Action Potential

Back 79

"Spikes"
elec signal, long range, in neurons/muscle
activated by graded potential
APS do not degrade over time/dist
Freq. of AP Speed of muscles only slightly diff. duration of how long channels are open.

Front 80

Voltage-Gated Channels

Back 80

Open when memb. reaches particular voltage.
usually -+15-20 MV above rest. potential
all v-gated channels open together, causing AP
enter inactiv. staqte soon after opening making REFRACTORY PERIOD.

Front 81

Phases of the Action Potential

Back 81

REFER TO BOOK FOR PICTURE.

Front 82

Phases of AP: Depolarization to Threshold.

Back 82

(firing level) -1-
chemical/mechan- gated Na+channels open
Na+ enters down gradient
t=threshold
A++, all v-gated Na+channels open
TTX blocks fast v-gated Na+ Channels.

Front 83

Phases of AP: AP SPIKE

Back 83

-2-
since all v-gated Na+ channels open together all APs in one neuron are identical
Na+ enters, rapid depolarization to +20 mV
Doesn't reach Na+ equil pot. because some V-gated K+ channels also open

Front 84

Repolarization

Back 84

-3- V-gated Na+ channels close after 1-2 msec
K+ channels still open, K+ leaves, memb. pot. Fails

Front 85

Hyperpolarization

Back 85

-4-
Voltage goes below resting because extra K+ channels are still open.
Nearer to -90 mV (K+ equil pot.) than Na+ rest

Front 86

Return to Resting Potential

Back 86

-5-
extra K+ channels close
AP Can't move back because gates close

Front 87

Dendrites

Back 87

receive NT
no AP here, only graded potential

Front 88

Cell Body

Back 88

Axon Hillock at beginning of axon, high density of V-gated Na+ Channels
AP Starts here

Front 89

Axons

Back 89

Carry AP away
Speed of AP variable, Increase with increase diameter and with myelin
* AD JUMP BETWEEN N or R

Front 90

Myelin- Nodes of Ranvier

Back 90

cells surround axon and wrap layers of membrane
Elec. insulates axon, prevents elc. loss to IF
increase Speed
NOR- Spares between myelin- completes AP circuit

Front 91

Refractory Period

Back 91

After V gated channels lose they are unopenable)
for a time (30-200 msec)
no new Ap's at this time limit AP frequency
AP only travels in ONE DIRECTION

Front 92

Frequency of Action Potentials

Back 92

All APs are identical in a given cell
info is passed by teh frequency, not size of APs
more APs create a stronger signal input to the CNS

Front 93

L8- Synaptic Structures

Back 93

Neural- Neural Synapses

Front 94

Presynaptic Neuron

Back 94

end of axon-synaptic knob, terminal button
receive AP down axon, AP opens Ca++ channels

Front 95

Vesicles

Back 95

contains NT
increase Ca++ triggers merger with cell membrane
NT dumped into (left, diffuses to post-syn membrane)
produce graded pot. in next cell.
Higher Ca++ out than in exocytosis.

Front 96

Postsynaptic Cell

Back 96

has receptors for NT from pre-syn neuron
receptors connected to ion channels
when NT binds to recep, channels open
NT IS THE CONNECTION BETWEEN CELLS
--elec. activity + chemical bridge
* CELLS IN BRAIN NEVER TOUCH

Front 97

Excitatory Postsynaptic Potentials- EPSPs

Back 97

NT binds and Na+ channels open,
Na+ enters > depolarization
NT causes dep or hyperpol. one EPSP is not enoug to reach threshold.
(112 mV)
NT Causes Dep or Hyperpol.

Front 98

Inhibitory Postsynaptic Potentials-ISPS

Back 98

BRAIN IS MOSTLY INHIBITING.
K+ of Cl- channels opened by NT
K+ leaves or Cl- enters down their elec. chem gradient
Memb potential= more -
less likely to reach threshold

Front 99

Grand Postsynaptic Action Potential

Back 99

Sum of all EPSPs and IPSPs
reach thres.? yes > five Ap
most neurons are inhibited

Front 100

Axon Hillock

Back 100

at junction of cell body and axon High D of V-gated Na+ channels
AP STARTS HERE

Front 101

One-Way Conductance

Back 101

NT is only released from pre-syn neuron, recept. only on post-syn.
info only goes in one direction

Front 102

Spatial Summation

Back 102

EPSPs from different neurons are additive
sum may reach threshold
some neurons receive syn. from thousands of other neurons.

Front 103

Temporal Summation

Back 103

EPSPs from same neuron close in time are additive> sum to reach threshold
ONE SYNAPSE W/ 2 DEPOLARIZATIONS close.
BRAIN NEEDS A SIGNIFICANT AMT IN TIME OF STIMULUS
PURPLE BOX-most common nothing happens.

Front 104

Convergence

Back 104

(anatomical)
Multiple synapses info a single neuron
Anatomical basis for spatial summation
(adding up elec. from diff syn)

Front 105

Divergence

Back 105

Each axon has many synaptic knobs (terminal buttons)
An AP in one neuron delivers NT to all it's divergent neurons at same time.
* Fine Control
Ex: light pat or hard pat?

Front 106

L9- Intercellular Communication---
Communication Types

Back 106

Communication between cells over short/long distances
combinations of electrical and chemical activity
No regrowth of muscles or neurons

Front 107

Paracrines (small)

Back 107

EDRF-1st
local
released from one cell, a ffects nearby cell
nitric oxide-control of blood flow
produced by endothelial cells or arterioles
*dilation> BP

Front 108

Neurotransmitters

Back 108

specific each neuron has only one type of NT variable neural cell length- NTS work locally as released
released by exocytosis-synapse cell to cell
* neural to neural muscle, endocrine cells
Rapid removal diffusion, digestion, reuptake

Front 109

Endocrine

Back 109

released by endocrine tissue (endothelial)
Broad effects>released into blood>everywhere
effects depends on target cell receptor

Front 110

Neurohormones

Back 110

(2) oxytocin, basopresin
released from neurons into the blood
functions as other hormones--receptor dependent
intermediates often inactive: androstenedione
> givs males more testosterone

Front 111

Hydrophilic/Hydrophobic

Back 111

philic>cannot cross membrane
rely on recep. activation
>member proteins produce 2nd messengers
Phobic-diffuse easily
-need transport + molecules in watery environment
-steroids, T it, Vit, A & D
increase prot. synthesis by activating genes
wide spread action many side effects

Front 112

Second Messengers

Back 112

made @ made
internal activation by philic hormone (1st mess)
only cells w/receptors respond

Front 113

cAMP (ring)

Back 113

ATP-cAMP- activate kinases, adds P to molec. kinase cascades amplify signals
individualized effects on diff. cells.
Activation: Increase Ca+
2. Phosphoryl

Front 114

cGMP

Back 114

GTP-cGMP activates Kinase

Front 115

IP3

Back 115

causes release of intracellular
Ca++ stores Ca++ stored in sarcoplasmic reticulum , a structure modifies form ER

Front 116

Nuclear Receptors

Back 116

form interphace between hydrophobic hormones and genes.
Determine which genes activated by phobic hormones
cells basis for side effects
PHILLIC- FAST CHANGE
PHOBIC-SLOW CHANGE

Front 117

Gap Junctions depolarize occurs muscles contract in adj. cells by opening Ca++ channels spread elec. act.

Back 117

FACT

Front 118

Calcium

Back 118

released from SR by IP3
BINDS TO/ALTERS PROTEIN ACTIVITY.
CELL TO CELL Ca++ signal--coord. cilia waves, exocytosis

Front 119

G Proteins

Back 119

Timing proteins
Bind GTP-and increase activity until GTP>GDD regulate vesicle movement, cytoskeleton, growth, vision and 2nd messenger.