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physiology 1330
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Physiology
Undergraduate 1
01/08/2009

Additional Physiology Flashcards

 


 

Cards

Term

Physiology

Definition
 is the study of how the body functions.
Term
Homeostasis
Definition

Homeostasis is the constancy of the internal environment.

- cells and only survive within a narrow range of conditions

Term
Examples of states that must be maintained for the cell to survive
Definition

pH, temperature, carbon dioxide, oxygen, blood pressure, wastes, intra and extra cellular fluid volumes.

Term
disease
Definition

Disease is a failure to maintain homeostasis

Term
systems that maintain homeostasis
Definition

nervous and endocrine systems

Term
examples of why you might need to derive from homeostasis
Definition

sudden fright, growth and pregnancy

Term
To regulate HS
Definition

1)Change in internal or external environment must be detected or anticipated

2) NS and/or endocrine response alters system(s), responsible for that condition.

3) For an anticipatory response:

Ex. You get an increase in resp. rate just before you start exercise. What normally blood gases are reasonable for change, but because you haven’t started yet this is before they are changed. Because you have proprioceptors they signal movement. These receptors can be learned and even behavioural. (ex. Putting on a coat before going out in the cold.)

4) Feedback mechanisms (both NS and endoc mechanisms)

- these are mechanisms that respond to change in the system

Term
set point
Definition

a range of values of the variable, which do not bring about a response. So this is where you are in HS, it is “normal”

Term
feed back
Definition

monitor information (input) and sends is back to the NS or and endocrine system

Term
negative feedback (NF)
Definition

the most common HS control mechanism. The result of the output moves the variable back toward the set point that is in the opposite (negative) direction, to the change that triggered the initial response. Hence negative, going in the opposite direction.

Term

True or false:

the set point can not be reset

Definition
false
Term
Positive Feed back
Definition

 

- less common and it is NOT homeostatic

- output intensifies the input

Term
Components of the Cell membrane
Definition

1)phosolipid bilayer

2) membrane proteins

3) membrane carbohydrates

4) bulk flow

Term
phospholipid bilayer
Definition

 

- continuous layer

- a barrier to water soluble molecules

Term
Types of membrane proteins:
Definition

a) transport proteins

b) receptor proteins

c) enzymes

d) joining proteins

e) identifying proteins

Term
transport proteins
Definition

transport proteins

I) channels

- form a pore in the membrane

- permit the movement of water and ions

- lots of them are specific channels that allows certain ions

- they can be gated (open or close like a door)

- they can be non-gated (always open)

II) Carrier proteins

- bind solute and carry it across the membrane

Ex. Glucose transport

- facilitated diffusion or active transport

Term
Receptor proteins
Definition

 

- can bind specific intracellular molecules (hormones or neurotransmitter- nt)

Ex. Insulin binds to a receptor that is specific to it, it only binds to insulin, and binds it to receptor on sk.muscle or adipose tissue which triggers movement of glucose transporters into cell membrane to increase glucose movement of glucose from blood to cells.

Term
Enzymes
Definition

 

- control chemical reactions on inner or out surface

Ex. Acetichlornesteras which is found on sk. Muscle and on some post synaptic neurons.

Na+/K+ - ATPase which is found in every cell in the body

Term
Joining proteins
Definition

 

- anchor cell membrane to cytoskeleton or to adjacent cell

-they can be junctional proteins, which are between cells, they form :

I) desmosomes

II) tight junctions

III) gap junctions

- extra cellular fibres (usually glycuproteins)

Term
Identifying proteins
Definition

 

Ex. Major mistocompatibility complex (MHC) proteins, which are on the surface of cells (expect the RBC). These identity cells as being part of the body. The RBC do have identifying proteins but not this kind.

Term

Membrane Carbohydrates

 

Fig. 3.4 pg.68

Definition

 

- most commonly glycoproteins but they can be glycolipids

- allow cell to recognize type ie. Other neurons, muscles cells…..

Term
Passive processes
Definition

Passive processes

- no energy is required

à movement from high concentration to lower concentration (like riding a bike down a hill)

Term
Types of passive processes
Definition

1) simple diffusion 

2)Facilitated Diffusion

3) osmosis

Term
Simple diffusion (solute movement) fig. 3.6 pg. 71
Definition

 

- solute can cross the membrane bilayer (fig 3.7)

- they have to be small and generally lipid soluble (O2, CO2)

- OR ions moving across membrane via protein channel by diffusion (from high

To lower concentration

Term
Facilitated Diffusion
Definition

 

- big charged or water soluble molecules

- molecule moves across the membrane down it’s concentration gradient, using a specific carrier protein.

- requires no energy

Ex. Glucose transport into liver, sk.muscle

Term
Osmosis (solvent movement)
Definition

Osmosis (solvent movement)

- it can get across, but we don’t know how

- the movement of water across the semi permeable membrane. A semi permeable membrane is permeable to water and nothing else, this is due to the water concentration difference via pore (protein) or across the bilayer.

Term
Osmotic pressure (OP) fig. pg. 73
Definition

 

- the pressure that most be applied to prevent movement of water from pure water solution (S1) across a semi permeable membrane into another solution (S2).

Term
Tonicity
Definition

 

- the response of a cell immersed in a solution

- depends on the conc’n of solutes (and the permeability of cell membrane to solutes)

Term
Hypotonic solution
Definition

 

- cell swells (takes in water), the outside has a high conc’n of water then the inside and the membrane is permeable to water so the water can get in, it has a lower OP compared to the cytoplasm.

Term
Isotonic solution
Definition

 

- the cell neither shrinks nor swells, it is happyJ

- for humans 0.9% NaCl is normal saline

Term
Hypertonic solution
Definition

 

- the cell shrinks when placed in this solutions and is unhappyL

- the outside has a lower conc’n then the cytoplasm, therefore it is more concentration and has a higher OP then the cytoplasm.

Term
Uses of tonicity:
Definition

 

- swelling and shrinking of certain cells uses to regulate fluid conc’n in the body (tonicity of fluids)

- 10% sucrose solution can be used to reduce brain swelling in brain injuring.

Term
Bulk flow
Definition

 

- movement of fluid due to a pressure gradient

Term
hydrostatic pressure
Definition

pressure of a fluid pressing against a surface ex. Cell membrane, blood vessel wall (BP)

Term

Direction of fluid movement into/out of capillaries determined by balance of

Definition

a) hydrostatic pressure ( fluid on both sides)

b) osmotic pressure due to presence of large non-diffusible proteins

Term
Active process
Definition

1) active transport

2) vestibular transport

Term
active transport
Definition

- substances move again conc;n gradient (low to high)

- protein- carrier mediates

- may be primary (1) or secondary (2)

Term

primary active transport

 

fig 3.10 pg. 76

Definition

1=pumps - ATP brakedown is part of the transport process

Ex. Na+/K+ - ATPase

 

a) Na+ gradient established by Na+/K+ ATPase (ATP use step)

Term

secondary active transport

 

 fig 3.11 pg.77

Definition

2= co transport

Ex. Glucose entry at small intestine

 

b) glucose, Na+ both must bind to carrier and they are co transported into the cell

à Na+ moving down it’s conc’n gradient drives in glucose against it’s glucose conc’n gradient. This is the transport step, therefore the glucose transport is active.

Term
vestibular transport
Definition

- substance is surrounded by a membrane within a cell (a vesicle)

 

a)endocytosis

b)Exocytose

Term

endocytosis

 

pg.79

Definition

 - movement into the cell

I) phagocytises - large items taken into the cell ex. Bacteria (cell eating)

II) pinocytosis - (bulk phase endocytosis) fluids and dissolved substances moving

Into the cell (cell drinking)

Term

Exocytose

 

pg. 78

Definition

 - movement outside the cell

Vesicles containing hormones, enzymes, nt ect., fuse with the cell membrane and open to release contents into ECF, this required Ca2+

Term

Electrical properties result from:

Definition

1) ionic conc’n gradients across the membrane

2) permeability characteristics of membrane to ions

3) ionic conc’n differences across membrane (gradients)

Term
SEE DIAGRAM!!!
Definition

ORG- (=A-) = negatively charged proteins

Cl- repelled by ORG- so is higher outside than inside

Na+ and K+ conc’ns are due to and maintained by activity of Na+/K+ ATPase (pump) on cell membrane

Term

Permeability of membrane to ions

 

Fig. 11.8

Definition

a) gated

b) non-gated

Term
non-gated ion channels
Definition

- always open

- more K+ non-gated channels then Na+ non-gated channels

- cell membrane is more permeable to K+ then to Na+ at rest

- these channels (especially K+) are important in establishing the resting membrane potential

Term

gated ion channels (not involved at rest)

 

 Fig 11.6

Definition

- can open in response to various stimuli

I) membrane voltage changes= voltage gated channels

II) Chemical changes ex. Binding of nt or hormone = chemical gates

III) Other stimuli that can open channels are tempurature (thermal gates), mechanical deformation (mechanical gates)

Ions move through channels by diffusion, no energy is required, it is always passive

Term
Resting Membrane Potential (RMP) fig.11.7 pg.399
Definition

- charge difference just across the membrane when cell is not stimulated

=potential (voltage) difference across the membrane (-70mv) ie. Inside = 70 mv more negative than outside

Term

Na+/K+ ATPase (pump) - not a channel

Definition

- brakes down one ATP and uses that energy to pump three Na+ out and two K+ in à both ions are pumped against their conc’n gradients and therefore required energy (ATP) and so it active transport.

- maintains concentration gradient of Na+ and K+ ( contributes a little but does not determine RMP)

Term
More non-gated K+ channels than non-gated Na+ channels (membrane is more permeable to K+ than Na+ at rest)
Definition

- K+ is the major determinate of RMP

- K+ diffuses out of the cell down conc’n gradient, therefore the cell loses postive charge, but

Term
large organic ions inside the cell ex. Proteins (ORG-)=negative, they can not cross the membrane
Definition

 

- K+ moves out due to the conc’n gradient and the inside of the cell becomes more negative

Term

Diffusion of K+ out ___1__ , and the diffusion of Na+ in ___2___ due to the increasing negative charge. At first, the postive out (K+) is ___3__ than the positive being drawn in (Na+) via the negative charge. Over time the inside of the cell becomes ___4__ enough that the amount of positive moving out balance the amount of positive moving in.

- the net movement of charge is 0. (positive is the same in both directions) and at that point you have the RMP)

Definition

1) slows

2) speeds up

3) greater

4) negative

Term

Polarized Membrane

Definition

- two poles, one positive, one negative

- unequal distribution of charge ( a potential or voltage difference = -70 mv in neurons)

- present in all cells

Term

Electrically Excitable Cells

Definition

- can depart from resting membrane potential, which is called action potential (ap), in response to stimuli (changes in external environment)

- muscle and nerve cells only

Term
When a neuron is stimulated
Definition

 

a) mp changes = a graded potential if the membrane reaches a threshold potential

b) triggers an action potential

Term

Graded potential

 

fig 11.10 p 401

Definition

Graded potential fig 11.10 p 401

- a small change in mp (away from resting)

- usually occur on a dendrite or a cell body

- this small change causes the ions to move, they travel passively a short distance ( current flow) - short lived

- magnitude and the distance travelled by the potential ( or current) varies directly with the strength of the stimulus fig 11.11 p.402

Term

changes in the graded potential can be either :

Definition

 

a) depolarization

b) hyperpolarisation

Term
depolarization
Definition

inside face of the membrane becomes more positive than resting

Ex. From -70mv to -60 mv (closer to zero) fig 11.9 p.400

Term
hyperpolarisation
Definition

 - inside face of membrane becomes more negative then RMP

Ex. From -70mv to -80mv

Term
repolarisation
Definition

a return to resting after either hyper or de polarization

Term

Why are graded potentials important?

Definition

- if it is a depolarization and if it is large enough ( or sums to be large enough) I.e. cause by a critical stim à will lead to an action potential

You have to get:

1) a critical stim à

2) graded potential à

3) action potential

Term
Action potential (impulse) -
Definition

a large change in MP that propagated along an axon with no change in this intensity

- initiates at trigger zone table 11.1 p.342

Term
what are the two possible outcomes of a stimulus?
Definition

1) hyperpol. Or too small (dies out) OR 2) depolarization to a threshold potential (around -55mv) which means it was a critical stimulus and we get an action potential

Term

 

SEE DIAGRAM
Definition
Term
absolute refractor period
Definition

 

- no action potential can be generated regardless of the stimulus size

- either 1) all Na+ channels are open (region 2) or 2) they are all inactivated ( cannot reopen until MP passes RMP ) region 3

Term
relative refractory period (region )
Definition

- period can be generated, but only by greater than normal stim.

- Na+ channels are reactivated when the MP passes RMP on repolarization, therefore they are closed but can be opened

- K+ channels are open and the membrane is hyperpolarised

- further to go to get to threshold and therefore you need a larger stim. And a larger graded potential

Term
All- or not principle of APs
Definition

 

- each time an action potential is produced it looks the same, that is it has the same max. depolarisation ect.

- strong stim à get AP (looks the same as previous)

- weak stim. (below critical) à no AP

Term

Compasision of AP and GP (CAG)

 

location

Definition

ap - axon

 

gp - dnedrites of cell body

Term

CAG

 

strength of MP

Definition

ap - all or none

 

gp - variable

Term

CAG

 

summation?

Definition

ap- no

 

graded - yes

Term

CAG 

 

repolarisation

 

Definition

 graded - Current dies away

 ap- Na+ gates close, K+ gates open

Term

CAP

 

types of gates

Definition

graded 

Chemical, mechanical etc. (anything but voltage)

ap - voltage

Term

CAG

 

distance travelled

Definition

graded - Short and then dies away

ap - Produced anew on the axon and propagates over long distances

Term
Action potential propagation
Definition

 

- depolarization during APà positive charge moves toward more negative charge on the adjacent membrane

- depolarization à is large enough to reach threshold à get AP on the adjacent resting membrane

- get a sequence of AP s along the membrane, each one the same

Term

Action potentials move ___1__philologically because the preceding membrane is still in it’s ___2__

Definition

1) in one direction

2) refractory period

Term
Rate of propagation depends on:
Definition

 

1) fibre diameter - the larger the diameter the fast the propagation (less resistant to current)

2) whether the fibre is myelinated

a) myelinated fibre AP occurs at nodes of ranvier = saltory (leaping conduction) à fast

b) un myelinated fibres Aps all along fibre = continuous conduction = slower

Term
Type A fibres
Definition

 - large diameter and they are myelinated à 130 M/sec (most sensory neurons and motor neurons to sk. Muscles fibres)

Term
Type C fibres
Definition

 - small diameter and un myelinated à 0.5 M/sec ( autonomic nervous system and some pain fibres)

Term

describe synaptic transmition in terms of AP

and Ca2+

Definition

Presynaptic cell à postsynaptic cell fig 11.18 p. 356

- AP arrives at axon terminal

- Ca 2+ enters synaptic end bulb of the terminal via Ca2+ - voltage gates (Ca2+ = low inside)

- Ca2+ triggers exocytose of the neurotransmitter à nt crosses cleft, binds to receptor on postsynaptic membrane à chemically gated channels open à graded potential

= postsynaptic potential (PSP)

Term

Excitatory PSPs (EPSPs)

Definition

= graded pot. Depol.

- due to opening of Na+ ( or Ca+) channels, or closing of K+ channels

- nt is often = ex. Acetylcholine (ach)

Term

Inhibitory Psps (IPSPs)

Definition

= graded potential à hyperpol.

- due to the opening of K+ channels or Cl- channels

- more difficle to get an AP

- nt often ex. Glycine

Term

1 neuron has many synapse à sum of all __1__ and ___2__ arriving determines if an action potential will occur at the axon hillock

Definition

1) EPSPs

2) IPSPs

Term
Neuro-muscular junction
Definition

 

à ach

- opens Na+ chemical gates on muscle end plate

- grader potential = end plate potential (EPP)

Depol. Is sufficient to get an AP on the adjacent sarcolemma

- lots of ach is released and therefore you always get an AP from and EPP

Term

Interpretation of sensory stim.

Definition

1. Stimuli detected by receptors

2. Receptors can be

a) dendrites on unipolar neurons

b) individual cells which synapse to neurons

Ex. Hair cells in the ear

Term

What happens when a receptor is stimulated?

Definition

1) the stim. Causes opening of channels (usually they are Na+ channels) on receptor membrane

2) à graded potential on receptor membrane (stim. Becomes electrical) = receptor potential

Term
If the stimulus is on the dendrite of a unipolar cell (aka generator potential) then:
Definition

= graded potential (depol.) which directly generates an AP on that neuron

Term

if the stimulus is on an individual cell (aka receptor potential) then :

Definition

( no AP on the receiving cell)

à nt onto the associated neuron à generator potential à AP on the neuron

Term

Types of receptors

Definition

1. phasic receptors

2. tonic receptors

Term
Phasic receptors
Definition

 

- show adaptation (usually decrease in sensitivity)

- get decrease in AP frequency to the CNS even though the stim. Is maintained at constant strength

Ex. Touch à clothes on skin

- receptors respond to a stim. Change (clothes fall off)

Term
Tonic receptors
Definition

 

- do not show adaptation (or takes a long time)

- give continuous info

Ex. Posture, condition (are things working properly) and painà protective

- monitor presence and intensity of stim.

Term

How does the brain perceive different types of stim?

Definition

- mainly by type of receptor stimulated

- mostly by the pathway that it takes and where it goes in the brain

- the axon activated by the receptor will make the same synaptic connections to the CNS concerned with that sense (hardwired from the receptor to the brain)

- always knows “who” is calling (type of receptor) and from where (location)

Term

How does the brain perceive stim. Of different strengths?

 

Ex. A feather or a brick on your foot

Definition

- mainly by the frequency of Aps ( the number per unit time) going to the CNS

- stronger stim. Also activates larger number of receptors ex. Pressure and touch

Term

Physiology of Vision

 

fig 15.10

Definition

 

1) light image which is focussed on the retina (reduced and inverted)

2) stimulates chemical reaction on the rods and/or cons which produces a receptor potential (graded potential)

Receptor potential à nt à bipolar neurons à release nt à ganglion cells à ntà AP à optic nerve (II) à optic tract à visual cortex or occipital lobe)

 

Term
So guys some of the notes are missing cause I missed the first part of class and the way the person that lent my the notes didn't transfer well
Definition
 
Term
Preganglipnic neuron =
Definition

 cholinergic

Term
Postganglionic neuron
Definition


= adrenergic (ne = norepin por cholinergic

Term
function of the post and pre ganglionic neurons
Definition

Func.  prepares body for activity - fight or flight

Term
NE- broken down by ____________ in presynapsic neuron
Definition
MAO (monoamine osidase)
Term
Function of the PSNS
Definition


- rest and digest “house keeping”
Term

Most organs innervated by ans have both SNS and PSNS, and the effects are usually _____________

Definition
opposite
Term

Effect

SNS

PSNS

Pupils of eyes (iris musc.)

dilate

constrict

Definition


SNS

dilate

 

 

PSNS

constrict

 

 

 

 

 

 

Term

Effect

SNS

PSNS

     

heart

Increase heart rate and force of contraction

Decreases heart rate

Definition

SNS- Increase heart rate and force of contraction

 

 

 PSNS - Decreases heart rate

 

Term

Effect

SNS

PSNS

     


   

GI tract





 

Definition

SNS - Decrease motility

 

PSNS- Increases motility

Term

Effect

SNS

PSNS










Blood vessels (sm. Muscle)


 

Definition
SNS - Vasoconstriction * no innervations (mostly except penis and clitoris)
Term

Effect

SNS

PSNS

     
     
     
     

Glands (sweat)


No innervations

Definition

SNS - Increase secretion (cold sweat)

 

PSNS - No innervations

Term

Effect

 

digestive

SNS

PSNS

Definition

digestive

Decrease except saliva

Increases secretion

Term

Effect

 

Genitals

SNS

PSNS

Definition

genitals

Ejaculation (male)

Erection and lubrication (both)

Term

3 types of movement

Definition

Reflexes

Voluntary

Rythmic

 

Term
1) reflexes
Definition


a) spinal - least complex required sensory input from ex. Muscles spindles

b) postural - for balance, posture

- require sensory input from ex. Proprioceptors (muscle spindles ), eyes, inner ear à co-ordinated by cerebellum

Term
2) Voluntary
Definition

- most complex - no external stim. Required (will)

Term
3) Rhythmic
Definition

- walking, running, etc.

- reflex and voluntary

- initiated and ended but cerebrum

- sustained without input from cerebrum

- input does to the motor neurons from

Term

Levels of Motor Control

 

Definition

1)Premotor

2)Supplementary Motor

3)Association Areas

- these three are level one

- they signal to the primary motor cortex, which is level two à

 

- the brain stem nuclei (level 3) à spinal cord (level 4) but the primary motor cortex can also send messages directly to the spinal cord, this is called the cortico-spinal tract

- the basal nuclei also get messages from the first level and second level. The spinal cord goes down to the muscles

Term
Level one -
Definition

- decides what movement is needed. 

- Plans sequences of muscle contractions. 

- Signals the primary motor cortex, it also sends a copy of the plan to the cerebellum

Term
Level two signals:
Definition


a) directly to the motor neuron (corticospinal tract). Fine, skilled movements

b) to brain stem nuclei à descending motor tracts go lower motive neurons = indirect tracts (extra pyramidal)- co-ordination of large muscle groups involved in maintenance of posture and locomotion

Term
Cerebellum
Definition

 - stores planned movement and compares the actual movement to the plan and then corrects it if necessary.

- receives sensory input about balance

- it has tracts going into the brain stem

Term
Basal Nuclei
Definition


 - involved in the planning and initiation of that movement

Term
Coritospinal (direct) pathway
Definition


- descending from the cortex to the sk. Muscles

- for fine, precise movement

Term
1) upper motor neurons ( they are actually inter neurons)
Definition


- cell bodies in the motor areas of frontal cortex

- axons travel down tracts to the sp. Cord

Term
2) Lower motor neurons
Definition


à sp. Nerves

- cell bodies are located in the ventral horn of the spinal cord

Term
1) Destruction of Upper motor neurons will result in
Definition


- reflex arcs are present

- get a) spastic paralysis

                - increased muscle tone (no muscle atrophy)

          B) exaggerated reflexes
Term
2) destruction of the lower motor neurons results in:
Definition


                                 

- no reflex arc present

- get a) flaccid paralysis - decreased muscle atrophy

          B) no reflex action

Term
Muscle Tone
Definition

- low level of contraction

Term
Speech
Definition


- complex

- involves areas in the left cortex in most ppl (99% of RT handed ppl and 66% of left handed)

Term
a) prefrontal cortex is reponsable for ____ part of speech
Definition


- necessary to understand written and spoken words (language)

Term
b) wernicke’s area, at the parietal/temporal lobe junction is reasonalbe for ____ part of speech
Definition


- sounding out unfamiliar words, and comprehension of language

Term
c) broca’s area is reasonable for ___ partof speech
Definition


- frontal lobe

- formulates words as they are to be spoken

- puts words together in a meaningful sentence

Term

Damage  to wernicke's will result in:

Definition

person can’t understand spoken or written words, but they can speak, but the words are meaningless, inappropriate or they are mixed but

Term
Damage to broca’s area wil result in: 
Definition

person can understand the language, but they can not produce sensible speech (can’t find the words and co-ordination of respiratory and oral movements may be poor)

Term
The Endocrine System
Definition


- glands and tissues that secrete hormones which travel in the blood to target cells (= cells with specific receptors)

- bind to receptors and change cell activity

- regualte growth reproduction, metabolism

- receptors - proteins and can be

Term
Describe the path sound waves take from the hair cells to the auditory cortex of thf temporal lobe
Definition
  hair cells in cochlear duct stim. (receptor potential)  
  [image]
 
           
               
               
  nt release          
  [image]
 
           
               
               
  generator potential        
  [image]
 
           
               
               
  action potential on neuron of cochlear branch on nerve VIII
 
 
  [image]  
 
           
             
             
  auditory cortex of temporal lobe      
Term
Describe how we maintain good posture
Definition
                   
      Hair cells of semicircular ducts and saccule and utricle  
      (= vestibule)          
      [image]
 
           
                   
                   
      receptor potential          
      [image]
 
           
                   
                   
      nt release          
 
                   
    [image]
 
  [image]
    [image]
    [image]
 
 
 
Term
Reflex
Definition
rapid automatic response to stimuli which which the stimulus always causes the same response, usually protective and involving 2 or more neurons
Term
Types of relfexes
Definition

Somatic relfex (E= skel. musc)

 

Visceral Reflex (E= sm./ cardiac musc. or glands)

Term
Types of Spinal Reflexes
Definition

Somatic spinal relfexes

 

Autonomic Spinal Relfexes

Term
Somatic Spinal Relfexes
Definition

Strech Reflex

 

Flexor (withdraw) Reflex

 

Cross Extensor Reflex

Term

Strech Reflex

 

Definition
  ie: knee jerk reflex (Extensor muscle contracts) (Fig.15.16)
  ╚ Stimulus is tapping patellar ligament    
     (Stretches muscle which in this case is quadriceps   
     femoris)          
  ╚ Receptor = muscle spindle (in muscle)    
  ╚ Effector is skeletal muscle (quadriceps femoris) and it
      contracts          
  ╚ Ipsilateral (same side)        
  ╚ monosynaptic (1 sensory neuron and 1 motor neuron)
Term
Flexor Reflex
Definition
  ie: in leg (flexor contracts)      
  ╚ stimulus is standing on a nail    
  ╚ Receptor = touch, pressure, pain    
  ╚ Effector is Hamstring (= flexor) and it contracts
  ╚ Ipsilateral (same side)      
  ╚ Polysynaptic (more than 1 synapse)  
Term
Cross Extensor Reflex
Definition
ie: in leg (extensor contracts)      
╚ Stimulus is stepping on a nail      
╚ Receptor = touch, pressure, pain      
╚ Effector is quadricep femoris (extensor) and it contracts
╚ Contralateral (opposite side)      
╚ Polysynaptic means more than 1 synapse    
╚ keeps you from falling down when flexor (withdrawl) reflex
    occurs (Fig. 13.19)      
Term
Reciprocal Innervation
Definition
╚ when muscle (group) contracts → agonist    
╚ at same time, antagonist prevented from contracting  
    (inhibitory neurons)        
  ie: stretch reflex in quadricep femoris is the agonist
        and it contracts the hamstrings which are the
        antagonists and are inhibited from contracting,
        that equals reciprocal innervation  
Term
Autonomic Spinal Reflex
Definition
Micturition reflex
Term
Micturition reflex
Definition
╚ urinary bladder        
╚ polysynaptic        
╚ stimulus = stretch of bladder    
╚ Receptor = stretch receptors in bladder wall
╚ CNS is in the sacral segment of spinal cord (PSNS)
╚ Effector is Detrusor muscle (wall of