exam 3 Flashcards
what is the systemic circuit?
the flow of blood between the heart and organs of the body
what is the function of the right atrioventricular (tricuspid) valve?
the prevent blood from flowing into the right atrium
which structure of the heart is responsible for its’ inherent rhythmicity
sinoatrial node
which layer of the heart is a serous membrane?
epicardium
in the cardiac cycle, what happens immediately after ventricular systole ends?
both the atria and ventricles fill with blood
which structures found at the connection between adjacent cardiac muscles are responsible for the quick transmission of a signal for the heart muscle cells to contract?
gap junctions
you have type O blood. what type of antibodies would you produce if exposed to A+ blood?
anti-A and anti-Rh
which capillary type allows for the greatest movement of large molecules across the capillary wall?
sinusoidal
what best describes the following pathway: heart > artery > capillary bed > vein > capillary bed > vein > heart
portal system
what part of a blood vessel contains the vaso vasorum?
tunica externa
which structures allow blood to pass through a capillary bed when the precapillary sphincters are closed?
metarterioles and thoroughfare channels
which type of artery is defined as being closest to the heart and having the largest diameter?
elastic artery
what makes up the formed elements of the blood?
erythrocytes, leukocytes, and platelets
what causes anemia?
a low red blood cell count
veins contain valves. What are those valves made of?
tunica intima
what part of a neuron contains the cell nucleus?
cell body
what is a bundle of myelinated axons contained within the central nervous system called?
tract
multiple sclerosis is a degenerative condition of the CNS that is thought to be an autoimmune disorder. Which cell is being attacked by the immune system?
oligodendrocyte
which pathway best depicts a polysynaptic reflex arc?
sensory neuron > interneuron > motor neuron
a somatic motor neuron carries what type of information?
motor commands to the skeletal musculature
which cell type would not be found in the central nervous system
satellite cell
what cell type is a macrophage of the central nervous system
microglical
the two cerebral hemispheres exhibit different functions and can operate independently of one another. in other words, each of the hemispheres is dominant for specific functions. what term is used to describe the function independence of the two hemispheres?
lateralization
what is a motor unit
one somatic motor neuron and all the skeletal muscle fibers it serves
which type of fiber tract connects two locations within a single cerebral hemisphere?
association
what is the epineurium?
a dense irregular connective tissue surrounding a nerve
the basal ganglia work with the cerebral cortex to help planned movements. which of the following conditions is caused by a failure in the basal ganglia pathway?
parkinson’s disease
which structures make up the brainstem?
medulla oblongata, pons, and midbrain
from which developmental region does the epithalamus develop?
diencephalon
what might a motor neuron look like
multipolar with its’ cell body in the gray matter of the spinal cord
which regions of the cerebral cortex have a homunculus
primary motor and primary somatosensory cortex
the white matter of the brain gets its look from the fatty, insulatory cells it contains. which cells are these, and what structures do they surround?
oligodendrocytes, axons
what is true of the primary somatosensory cortex?
it receives sensory information coming from the skin
where is Wenicke’s area located, and what is it’s function
temporal lobe; for recognition of the spoken work
after suffering a severe head trauma, an individual exhibited a major change in personality. damage to what region would have caused this
prefrontal cortex
what is secreted by the epithalamus and what is it’s function
melatonin; initiate sleep
what are the meningeal laters surrounding the spinal cord?
dura mater, arachnoid mater, and pia mater
which structure of the spinal cord exists because of the large number of neurons entering and exiting the spinal cord to serve the upper limbs
cervical enlargement
which two regions of the brain are considered to be the two major visceral control centers?
medulla oblangata and hypothalamus
what is a primary function of the cerebellum
coordination of movement
what is cerebrospinal fluid
a blood filtrate produced by the choriod plexus
which of the following would you find in a nerve
sensory neuron, schwann cell, motor neuron, dense connective tissue
what would you not find in a nerve
interneuron
the sciatic nerve is a large nerve that serves the posterior region of the lower limb. which plexus does it arise from
sacral
which division of the automatic nervous system initiates a short term response that mobilizes the body during an extreme situation
sympathetic
which neurotransmitter is released at a neuromuscular junction of a motor unit
acetylcholine
where do the preganglionic and postganglionic neurons of the sympathetic division of the automatic nervous system synapse
within sympathetic chain ganglia
what is the systemic circuit
route between the heart and tissues of the body (other than the lungs)
route of the systemic circuit
left ventricle > aorta > cells of body > veins > right atrium
what is the fibrous pericardium
tough outer layer of sac that anchors heart and prevents overfilling
dense irregular CT
what makes up the serous pericardium
parietal, visceral
pericardial cavity
parietal layer of heart
inner layer of sac, secretes serous fluid
visceral layer of heart
outer layer of sac, secretes serous fluid
paricardial cavity
space between parietal and visceral; filled with serous fluid
what is the myocardium
cardiac muscle tissue
what is the endocardium made up of (cell type)
simple squamous epith
right atrium: veins
superior and inferior vena cava - large veins that return deoxygenated blood
R. atrioventricular: tricuspid valve
separates right atrium from the right ventricle
right ventricle: chordae tendineae
dense reg CT that attaches cusps of tricuspid valve to ventricle wall by the papillary muscle and the pulmonary semilunar valve
what is the papillary muscle of the heart
projection of cardiac muscle
what does the pulmonary semilunar valve do
separates right ventricle from pulmonary trunk (artery)
Left atrium - veins
return oxygenated blood to heart from lungs
L. atrioventricular valve: bicuspid/mitral
separates left atrium from left ventricle
left ventrical: chordae tendinae
dense regular CT that attaches cusps of bicuspid valve to ventricular wall by papillary muscle, aortic semilunar valve, and myocardium
aortic semilunar valve
separates left ventricle from aorta
myocardium
left ventricle has the thickest layer of cardiac muscle
blood flow thru the heart
blood low in oxygen enters right atrium –(thru tricuspid)–> right ventricle –(pulmonary semilunar)–> lungs > left atrium –(thru biscupid)–> left ventricle –(semilunar valve)–> oxygenated blood to the body
Sinoatrial node
in right atrium, initiates electrical impulse (pacemaker)
internodal pathway
carries impulse away from SA node to AV node
atrioventricular node
delays impulse before passed on to ventricles
fibrous skeleton
barrier between atria and ventricles that prevents an electrical impulse from passing
atria contract what way
top to bottom
ventricles contract what way
bottom to top
right coronary artery deoxygenated or oxygenated
deoxygenated
layers of vessel walls
tunica intima- endothelium (simple squa), subendothelial layer (loose areolar CT)
tunica media
arterial walls vs veins
thicker and stronger than veins under higher pressure
tunica externa of veins vs arteries
veins are of equal thickness or thicker
tunica media of artery vs veins
artery thicker with more elastic fibers
elastic artery
largest - branches near heart
high concentration of elastin in tunica media - quick recoil
muscular artery - tunica media
less elastin and more smooth muscle; more control over lumen size
sheets of elastin surround and support smooth muscle
internal and external elastic membrane
arterioles
branches of muscular arteries, constrict and dilate quickly, larger (all 3 tunics and lamina), smaller (tunica media and endothelium only)
smaller as it approaches capillaries
capillary permeability
continuous > fenestrated > sinusoidal
veins
thinner walls that comparable arteries - lower blood pressure
venules (drain capillaries) < medium (drain venules) < large (drain large regions back towards heart)
have valves
leukocytes (white blood cells)
complete cells, diapedesis (squeeze thru capillary walls), immune response
Central Nervous system
Brain and Spinal Cord
integration and interpretation of sensory input
dictates motor reponse
Periipheral Nervous system
cranial nerves and branches
spinal nerves and branches
neurons transport sensory input
towards CNS
neurons transport motor input
away from CNS
sensory receptors monitor what changes
external and internal
integration (nervous system)
activation of neurons processed by brain
peripheral nervous system has what neurons
sensory and motor
CNS has what neurons
interneurons
neurons
able to respond to stimulus and carry electrical impulse - excitable cells
supporting cells
help neurons to function effectively- non excitable
cell body (soma) contains
single nucleus and organelles
dendrite
receptive regions, carry info to cell body
axon
carry info away from cell body, one per neuron, can be short or long, end at axon terminals, often surrounded by myelin sheath
myelin sheath
insulates axon so action potential can travel more quickly
schwann cells
in PNS wrap around axon
myelinated axon
schwann cell wraps single axon, faster conduction
unmyelinated axon
schwann cell surrounds multiple axons, slower conduction
myelin sheaths in PNS
insulates axons so action potential travels more quickly
oligodendrocyte
cell that forms myelin sheath in CNS, multiple processes, each wrapping around an axon of a different interneuron
multipolar neuron
most common, axon and multiple dendrites, motor neurons and interneurons
bipolar neuron
only found in few locations, axon and single dendrites attached at cell body, special sensory neurons
unipolar neuron
typical sensory neuron, single axon connected via short process to cell body
which type of cell of the nervous system carrie’s an electrical impulse toward the CNS
afferent neuron
sensory neuron - PNS
afferent, cell bodies clustered in ganglia, unipolar
motor neuron - PNS
efferent, cell bodies within CNS, multipolar
interneurons - CNS
majority of neurons of body, multipolar
the PNS is split into visceral and somatic divisions. which are included in the visceral?
liver, stomach, heart, blood vessels, lungs
(visceral = internal organs)
visceral functions
viscera are the organs within body cavities (smooth muscle)
somatic functions
skeletal muscle, skin
structure of nerve
cells - neuron, schwann
CT
blood vessels
what is the CT covering the fascicle of nerve fibers called
perineurium
structure of nerve - endo durian
surrounds axon, thin reticular CT
structure of nerve - perineurium
surrounds fascicle of axons, fibrous CT
structure of nerve - epineurium
surrounds whole nerve, dense irregular CT
synapse
site where neurons communicate with each other/other cells
presynaptic neuron
carrie’s impulse towards synapse, end at axon terminals
postsynaptic neuron
carries impulse away from synapse (activated neuron)
axon terminals
synaptic vesicles containing neurotransmitters (“bubble” moving action potential down to axon terminal, “popping” and merging into membrane)
neurotransmitters
acetylcholine and norepinephrine
released into synaptic cleft between synapsing neurons
axodendritic synapse
presynaptic axon to postsynaptic dendrite
axosomatic synapse
presynaptic axon to postsynaptic cell body
axoaxonic
presynaptic axon to postsynaptic axon
supporting cells of CNS
astrocytes, microglia, ependymal cells, oligodendrocytes
supporting cells of PNS
satellite cells and schwann cells
astrocyte
supporting cells surrounding capillaries and neurons, transfer glucose, take up excess neurotransmitters
microglia
smallest and least abundant supporting cell, protects brain from pathogens, macrophages!!!
ependymal cells
supporting cell, make up ciliated simple cuboidal epith of CNS
ventricles is brain, central canal of spinal cord, cilia aid circulation of cerebral spinal fluid
oligodendrocytes
form myelin sheath surrounding axons of CNS
satellite cells
around cell body, prevent info crossover where cell bodies are crowded
ganglia
clusters of neuronal cell bodies
what capillary rich structure found within the brain ventricles produces CSF
choroid plexus
which structure of the neuron do oligodendrocytes surround
axons
what does the telencephalon develop into
cerebrum
what does the mesencephalon develop into
midbrain
what does the metencephalon develop into
cerebellum and pons
what does the myencephalon develop into
medulla oblangata
what makes up the brain stem
midbrain, pons, medulla oblangata
cortex
cognition, personality, interpretation of sensory impulses, initiation of voluntary movement, communication
projection fibers in the brain
allows communication between cortex and nervous system (decussation - fiber crossover left and right)
commissural fibers in brain
communication between right and left cerebral hemispheres
cortex processing areas
sensory, motor, association areas (largest)
frontal lobe
primary motor cortex and premotor cortex (association area, coordination of learned motor skills)
prefrontal cortex
personality, cognition, intellect
parietal lobe
input and interpretation of sensory information coming from somatic senses
temporal lobe
sounds sensory info from inner ear, smell from nasal cavity
occipital lobe
primary visual cortex, visual association area
insula
middle of brain, gustatory cortex (taste)
basal nuclei (ganglia)
clusters of cell bodies deep to white matter of cerebrum, work with cerebral cortex for motor movements, unconscious control of skeletal muscles, striatum (intensity of movement)
amygdala
memory of fear, regulates anger, response to social cues
the diencephalon consists of which structures of the brain
thalamus, hypothalamus, epithalamus
superior colliculi
visual reflexes - ability to follow movements
inferior colliculi
auditory reflexes
pons brain
regulates respiration, bridge between cerebrum and cerebellum
cerebellum
smooths and coordinates muscle movement - current, planned, equilibrium (inner ear)
medulla oblangata
basic life support functions
which of the protective features surrounding the brain would also be found protecting the spinal cord
bone, meninges (travel down thru canal), CSF
protective structures of the spinal cord
subarachnoid space (circulating CSF)
epidural space (fat filled space around dura mater)
major fiber tracts in white matter of the spinal cord
ascending - sensory interneuron axons
descending - motor interneuron axons
gray matter of spinal cord
dorsal horn - motor function leave spinal cord
lateral horn - sensory function enter spinal cord
ventral horn - visceral motor neurons below cervical regions
dorsal roots transport …
sensory
ventral roots transport ….
motor
monosynaptic reflex
axon terminals of sensory neurons synapse directly with motor neuron within spinal cord
polysynaptic reflex
axon terminals of sensory neurons connected via one or more interneurons to a motor neuron
