Physio module 1 review

Above midbrain: Rostral

anterior

Below midbrain: rostral

superior

above midbrain: caudal

posterior

below midbrain: caudal

inferior

above midbrain: ventral

inferior

below midbrain: ventral

anterior

above midbrain: dorsal

superior

below midbrain: dorsal

posterior

anterior

front

posterior

back

ipsilateral

two points on same side of midline

contralateral

two points on opposite sides of midline

coronal slice

vertically oriented at 90 degrees to sagittal plane

horizontal plane

perpendicular to both sagittal and coronal plane

medial sagittal plane

when viewed dorsally, divided along midline into two equal halves

Soma

cell body of neuron

unmyelinated

axon

myelinated

carries action potentials from soma

dendrites

receives impulses from other neurons

gray matter

no myelin

neruonal cell bodies in CNS

ganglion

only in PNS (except basal ganglia in CNS)

white matter

myelin

axon groups in CNS

commissure

collection of axons connecting one side of brain to other

(crossover)

Meninges

covers brain and spinal cord

3 layers: dura mater, arachnoid mater, pia mater

outermost later of meninges

dura mater

inner most layer of meninges, highly vascular

pia mater

middle layer of meninges

arachnoid mater

afferent nerves

sensory info from periphery to CNS

(into CNS)

efferent nerves

carry info from CNS to periphery

(away from CNS)

motor nerves

efferent nerves carry info to skeletal muscles (leaving brain)

enteric nervous system

walls of GI tract

“gut brain”

autonomic nervous system

visceral functions such as digestion, blood flow, temp regulation, reproduction

contains sympathetic (fight or flight) and parasympathetic (rest and digest) nervous systems. and enteric nervous system

somatic nervous system

sensory and motor communication between CNS and skin, skeletal muscles and joints

cerebrum

largest part of brain

receives input from contralateral side of body (commissure)

thoughts, perceptions, voluntary actions

cortex

interchangeable with cerebrum

refers to surface of gray matter

what two things increase surface area in brain

gyri (folds; hills)

sulci (fissures, valleys)

cerebellum

behind cerebrum

key part of motor system, maintenance of balance and muscle coordination, position sense

damage to cerebellum

ataxia- jerky, poorly coordinated movements

brainstem

conduit of flow b/t cerebrum and spinal cord

regulation of vital body functions

Dorsal root

afferent info to the cord

always sensory

ventral root

carries efferent away from cord

always motor

most common passive transport

ion gated channels

hydrostatic pressure

name of force that opposes osmotic pressure

normal saline (NS) or isotonic

.9% NaCl

.45% NS or ½ NS

hypotonic, smaller osmolarity, cells swell

2, 3, 5% NS

hypertonic, larger osmolarity, cells shrink

ion responsible to depolarization in ear

potassium (K+)

ion responsible for rapid depolarization of membrane

sodium (Na+)

what is responsible for absolute refractory period

Na channels haven’t reset yet

what increases speed of conduction

myelin

how are electrical synapses joined

gap junction

fastest transduction/signaling

gap junction

what kind of receptor is at postsynaptic membrane in skeletal muscle that’s stimulated by Ach

nicotinic

what enzyme breaks down Ach in synaptic cleft

acetylcholinesterase

relationship between force and velocity

speed of shortening decreases as total load increases

ex: speed of bicep curl with 1 lb dumbbell vs 50 lb

afterload

weight muscle lifts after resting length established

force it must overcome

preload

force applied to resting muscle before stimulation

passive tension

how many fields of movement are detected by the ear?

5 fields

(3 semicircular canals, saccule and utricle senses)

utricle

horizontal (linear acceleration)

saccule

vertical (linear acceleration)

horizontal semicircular canal

left to right (shaking head)

(angular acceleration)

posterior semicircular canal

rotation in plane from left shoulder to right shoulder (angular acceleration)

superior semicircular canal

front to back (nodding head)

(angular acceleration)

otolith organs

utricle and saccule

linear acceleration

semicircular canals

superior, horizontal, posterior

angular acceleration

organ of corti

converts sound waves to electrical signals

allows you to hear music

too much smooth muscle stimulation causes what

asthma attack, hypertension

too little vascular smooth muscle stimulation can cause what

vasodilation-hypotension

Na+ equilibrium potential

+67

K+ equilibrium potential

-95

hyperalkemia

increase in serum K leads can lower Vm from -70 to -60 which can tigger action potentials leading to fatal arrhythmia

relative refractory period (RRP)

impulse can be evoked with stronger stimulus since few Na channels have reset

saltatory conduction

actions potentials only occur from node to node

nodes of ranvier

interrupts myelin sheath t regular intervals

graded potential vs action potential

graded potential - depolarization signals over SHORT distance

action potential - depolarization signals over LONG distances

absolute refractory period (ARP)

impossible to stimulate another AP bc Na channels have not reset

osmolar gap

measured (in lab) osmolarity greater than estimated (only Na, glucose, and urea concentrations)

caused by addition solutes in plasma

2 things to remember with Ca

exocytosis, contraction

difference between interstitial fluid and plasma

interstitial fluid has NO PROTEIN

comprarator

interpret input form sensors to detime deviation

set point

center of normal range, target value

sensors / receptors

monitor controlled variable

effectors

restore set point to normal level

examples of primary active transport

Na-KATPase pump

Ca-ATPase pump

MDR - multidrug resistance transporters → extrude molecules form cells

H/K-ATPase

examples of secondary active transport

symporters:

-na/glucose in intestine

-na/k/cl and na/cl uptake in kidney

antiporters:

-na/ca and na/h exchange

How does passive transport occur

only along favorable electrochemical gradient (no ATP, down gradient)

requires proteins

most common are ion gated channels

uptake of glucose

GLUT transporters

(facilitated diffusion)

what are postural muscles

slow twitch (type 1)

distance runners have more

main tone and resist fatigue

type II muscles

fast twitch, sprinters have more

fast brief movements, fatigue fast

visceral smooth muscles

cells arrange in large bundles behave as syncytium due to gap junctions

what type of smooth muscle is not connected by gap junctions

multiunit smooth musle (fine control)

Ca2+-calmodulin complex

formed from Ca2+ increase

stimulates myosin light chain kinase - active myosis

myosin light chain phosphatase

muscle relaxes when Ca2+ decreased

myosin dephosphorylated

myosin light chain kinase

stimulates

increased Ca2+ activates Ca2+-calmodulin complex, stimulates myosin light chain kinase and activates myosin

What muscle contraction does not contain troponin and what is used instead?

smooth muscle does not contain troponin, uses myosin phosphorylation instead

latch bridge state

maintenance of muscle tone without high rates of ATP

(because cross bridges can remain attached for extended periods)

what neurotransmitter do motor neurons release>

acetylcholine (Ach) at neuromuscular junction

what enzyme synthesizes Ach?

choline acetyltransferase

what ion responsible for excitation contraction coupling

calcium

quantum

amount of Ach in presynaptic vesicle

what breaks down Ach

acetylcholinesterase