anatomy and physiology exam four Flashcards
neuron
single (one) cell of the nervous system
nerve
bundle of axons; multiple neurons
nervous tissue
is excitable (allows signals to transmit fast; an immediate response to stimuli, etc.); generates an action potential from a resting membrane potential
cytokines
cell moving
interferons
cytokines that amplify our immune defense system against viruses (first line of defense)
what are the types of interferons?
I, II, III
what are the sources of interferons?
monocytes (macrophages), fibroblasts, T-cells/T-lymphocytes, virus-infected cell
cancers
uncontrolled mitotic division
ABCDE of moles
asymmetry, borders, color, diameter, evolution
why are cancers so deadly?
- “nutrition bullies” that steal nutrition from cells that are ok
- change in form = change in function
- non-muscle reference to actin = cancer can move, therefore it can METASTASIZE and get into the blood vessels
what occurs when cancer metastasizes and moves into blood vessels?
weakens blood vessels causing bleeding and ultimately resulting in internal hemorrhaging
anterior vs posterior pituitary
anterior: hypothalamic hypophyseal portal system, FLATPEG (hormones)
posterior: oxytocin and vasopressin (hormones)
portal system
when blood hits two capillary beds before going back to the heart
ex: hypothalamic hypophyseal portal system in anterior pituitary
anterior pituitary hormones
made and released at the anterior pituitary level
FLATPEG
Follicle-stimulating hormone (FSH)
Luteinizing hormone (LH)
Adrenocorticotropic hormone (ACTH)
Thyroid-stimulating hormone (TSH)
Prolactin
Endorphins
Growth Hormone (GH)
adrenocorticotropic hormone (ACTH)
acts on adrenal cortex to increase cortisol (stress hormone)
short-term stress
okay :)
long-term stress
bad :( cortisol levels increase, and when they stay high they inhibit white blood cells (immune system) making us sick
growth hormone (GH)
makes its way down the liver and up-regulates insulin-like growth factor 1 (used for growth and tissue repair)
stimulated systemic body growth where growth promoting effects on cells of what parts of the body?
skeletal muscle, bone, liver, kidney, nerve, skin, hematopoietic cells, lung, DNA synthesis
posterior pituitary hormones
made in the hypothalamus and released at the posterior pituitary level
oxytocin
antidiuretic hormone - ADH (vasopressin)
antidiuretic hormone - ADH/vasopressin
hormone that is against urine formation: ADH levels go up so urine volume goes down
what is an aquaporin?
a channel protein that transports water
how are aquaporins related to vasopressin (ADH)?
when dehydrated, aquaporins increase, meaning ADH (vasopressin) increases, which causes urine formation and volume to decrease
what inhibits vasopressin (ADH)?
ethanol (C2H5OH) and caffeine: allows for urine production to increase
-tropic and -tropin
hormone that affects another hormone
type II muscle soreness
24-48 hour muscle soreness after heavy lifting; leads to tiny micro-tears in the actin and myosin in muscles that need to be repaired by testosterone levels going up (in BOTH genders)
testosterone “T”
increase in testosterone turns on genes to promote tissue repair
-one and -ol
steroid hormone that turns on genes to repair tissues
what is the true muscle repair (muscle building) for type II muscle soreness?
stem cell recruitment
stem cell recruitment
adding nuclei from satellite stem cells that donate its nucleus in order for more genes for actin and myosin for transcription and translation to increase - proteins yay
testosterone and genetics
venoms, toxins, poisons
necrosis (tissue death); keeps the voltage-gated calcium channel open allowing acetylcholine to be released in synaptic cleft, resulting in increased skeletal muscle contraction that leads to tetany: paralysis
*venoms are vasodilators resulting in decreased resistance (low blood pressure)
snake bites
leads to necrosis (tissue death)
varicose veins
occur when veins and valves give out or are blown out; leads to back flow
what acetylcholine receptor is involved when encountering venoms, toxins, poisons?
nicotinic acetylcholine receptor
what are the two types of hormones (for this exam)?
peptide and steroid hormones
peptide hormones
hydrophilic; go through rough endoplasmic reticulum to golgi to be vesicalized; it is stored and then released when needed
bind to cell surface receptors (2nd messenger) and has fast effects (seconds to minutes)
ex: adrenaline/epinephrine
steroid hormones
from cholesterol, so they are hydrophobic; made and released in the smooth endoplasmic reticulum
THINK “-one” and “-ol”
bind to intracytoplasmic receptors; affects transcription by turning genes on or off and has slow effects (hours to days)
ex: testosterone
release of neurotransmitters
vesicle neurotransmitter is made in the soma (body) of a neuron; rotary proteins move the vesicles from the soma to the pre-synaptic membrane; action potential travels down the axon to the pre-synaptic terminal, causing a depolarization of the membrane; depolarization causes the opening of the voltage-gated calcium channels, allowing calcium in; calcium forces the vesicle to fuse with the synaptic terminal, further releasing acetylcholine into the synaptic cleft through exocytosis
dendrites
increase surface area
soma
site of all biosynthesis
rotary proteins
main function is to transport
Dynein and Kinesin
depolarization
action potential starts at threshold; then sodium coming in through voltage-gated sodium channel opened at threshold starts making the cell more positive BUT the channel closes at +35 millivolts
repolarization
potassium comes out through voltage-gated potassium channel opened at +35 millivolts making the cell more negative BUT begins to close around the RMP but ACTUALLY closes at -90 millivolts
hyperpolarization
goes below resting membrane potential so the inside of the cell is even more negative; less active because we are further from threshold
what occurs when we are farther away from threshold (hyperpolarized)?
1) we need a stronger stimulus to get back to threshold or 2) we are so hyperpolarized that it no longer functions
what is the relationship between the medulla oblongata and narcotics/opiotes?
it is okay when it only hyperpolarizes the pain centers
right hemisphere of brain
controls left side of body
left hemisphere of brain
controls right side of body
where do we see an increase in surface area in the brain?
wrinkles of brain and branching dendrites
what are the three major sections of the brain?
forebrain, midbrain, hindbrain
forebrain (prosencephalon)
consists of the diencephalon and telencephalon
diencephalon: consists of the thalamus, hypothalamus, epithalamus (contains pineal gland that produces melatonin which regulates our sleep-wake cycle)
telencephalon: consists of cerebral hemispheres (cortex), basal nuclei, limbic system
midbrain (mesencephalon)
alertness, awakeness, consciousness
contains reticular activating centers: wakefulness (caffeine hits receptors here)
reticular activating center
functions as a network of neurons that regulate sleep-wake transition and arousal; located in the brainstem above the spinal cord as well as the midbrain; acetylcholine, serotonin, dopamine, and histamine are the neurotransmitters involved
what substance is the adenosine receptor antagonist of the midbrain?
caffeine
hindbrain (rhombencephalon)
consists of the medulla oblongata, pons, cerebellum
medulla oblongata: blood pressure, heart rate, respiration, blood flow, swallowing, vommitting
pons: balance and posture
cerebellum: *coordination (spatial equilibrium), muscle tone, intricate movements, balance and posture
what three parts makes up the brain stem?
midbrain, pons, medulla oblongata
brain stem connects the brain to the spinal cord
pons
balance and posture
medulla oblongata
controls blood pressure, heart rate, respiration rate, blood flow, swallowing, vommitting
frontal lobe
voluntary movements and thoughts, *cognition (ability to think, reason, cause and effect), *long-term memory
parietal lobe
taste (gustation), temperature, touch, pressure, vibration
temporal lobe
emotions, speech, *smell (olfaction), *auditory stimuli, *short-term memory
occipital lobe
vision
where in the brain are the five senses found?
taste and touch are found in the parietal lobe, hearing and smell are found in the temporal lobe, vision is found in the occipital lobe
cerebellum
*coordination (spatial equilibrium), muscle tone, intricate movements, balance and posture
spinal cord
conveys information to and from the brain and generates basic patterns of locomotion
produces reflexes: walking, urination, sex organ function
reflex
body’s automatic response to a stimulus
example: knee-jerk reflex
what are the different types of pancreatic function?
endocrine, exocrine, paracrine, artocrine
endocrine (pancreas)
secretes hormones into the blood; islets of langerhans
what are the cell types of the endocrine function of pancreas?
alpha, *beta, delta
alpha cells
produces glucagon elevates blood sugar
beta cells
produce insulin lowers blood sugar
delta cells
produce somatostatin inhibiting gastrointestinal tract function
exocrine (pancreas)
secretes into the gastrointestinal tract; usually enzymes
paracrine (pancreas)
affects tissue “near” the pancreas
artocrine (pancreas)
affects itself
what cells are associated with blood sugar?
glucagon: elevates blood sugar
insulin: lowers blood sugar
insulin
beta cells in the islets of langerhans
GLUT-4
regulates glucose levels by transporting glucose into muscle and fat cells; GLUT-4 in the cell membrane lowers blood sugar
hypoglycemia
low blood sugar
hyperglycemia
high blood sugar
when hyperglycemia persists for a long time, what occurs?
GLYCOSYLATION: untreated hyperglycemia will cause sugars to crystalize, blocking blood flow; further turns into “sweet urine” or diabetes
type I diabetes
congenital (born with it); we cannot produce insulin at all because beta cells, that makes insulin, in the pancreas are attacked by the immune system
type II diabetes
usually during 40s/50s/60s; weight increases while physical activity decreases; we can produce insulin BUT there is insulin resistance (we are not using it well)
issues with insulin
issues with 1) amount of insulin or 2) tyrosine kinase receptor
tyrosine kinase
receptor that adds phosphate
central nervous system
consists of brain and spinal cord; where information is processed
peripheral nervous system
consists of 31 pairs of spinal nerves and 12 pairs of cranial nerves; somatic and autonomic peripheral nervous system
transmits information to and from the central nervous system, regulates movement, and the internal environment
afferent neurons transmit information to the central nervous system and efferent neurons transmit information away from the central nervous system as a response
somatic peripheral nervous system
voluntary; afferent and efferent; carries signals to skeletal muscles
afferent
sensory; into the spinal cord; bipolar neuron
efferent
motor; away from the spinal cord; skeletal muscle
autonomic peripheral nervous system
involuntary; three divisions including sympathetic, parasympathetic, enteric; regulates smooth and cardiac muscles
sympathetic
fight or flight (regulates arousal and energy generation); not default; stronger and faster because hormones are from adrenal medulla; 1) sympathetic chain and 2) hormones such as adrenaline/epinephrine; thoracic-lumbar nervous system
sympathetic ganglia
short pre-ganglionic receptors of acetylcholine and long post-ganglionic receptors of norepinephrine
parasympathetic
rest and digest (antagonistic effects on target organs and promotes calming and a return to these “rest and digest” functions); default system; weaker; cranio-sacral nervous system
parasympathetic ganglia
long pre-ganglionic receptors of acetylcholine and short post-ganglionic receptors of acetylcholine
sympathetic and parasympathetic
both systems have a pre-ganglia and a post-ganglia and a ganglion
ganglion
a group of cell somas (body) outside the central nervous system
dorsal root ganglia
sensory; cluster of neuronal cell bodies located outside the central nervous system
enteric
gastrointestinal tract
why can’t action potentials summate?
refractory period
absolute refractory period
“absolutely” no new action potentials during this time; voltage-gated sodium channel “gates” are resetting
THINK during repolarization
plateau phase
cardiac muscle action potential due to potassium out and calcium in counteracting each other
in cardiac muscle; means there is a longer absolute refractory period so that cardiac muscle cannot summate the twitches = no cardiac tetany but inhibiting the cardiac muscle summation
promotes ventricular emptying because of longer, sustained contraction of the heart
relative refractory period
a new action potential can be generated but there would need to be a stronger stimulus to get back to threshold
THINK during hyperpolarization
saltatory conduction
action potential jumps from node to node; myelin
myelination
done by schwann cells in the peripheral nervous system and oligodendrocytes in the central nervous system
action potential conduction velocity (APCV) + myelination
myelinated sheaths are faster sheaths (thicker)
length of axon does not matter but DIAMETER of axon does as thicker equals a faster nerve
leak channel
ion channel that is always open, allowing ions and substances to pass through; passive channels or non-gated channels
voltage-gated channel
transmembrane protein that opens and closes in response to changes in a cell’s electrical potential
ligand-gated receptor to channel
protein embedded in a cell membrane that acts as a gate, allowing specific ions to pass through only when a signaling molecule (known as a ligand) binds to it
opening the channel by triggering a conformational change in the receptor protein
carrier
membrane protein that moves molecules across a cell membrane
pump
generates a membrane potential by creating an electrochemical gradient across the membrane (against the concentration gradient)
Guillaini-Barre Syndrome (GBS)
is sudden (hour to days) and progressive, causing muscle weakness up to paralysis (skeletal)
what occurs prior to the onset of GBS?
antecedent infections (no known cause)
antecedent infections
first a virus (like mononucleosis), then a bacterial infection (like a tonsil infection), and finally a respiratory infection (like pneumonia)
- viruses
- bacterial infections
- respiratory infections
what are the types of painkillers (neuro + pharmacology)?
local or systemic
local painkillers (anesthesia)
“-caines” that block the source and usually block the voltage-gated sodium channel: local injection blocks and stops depolarization, stopping the transmission of pain signals from the site of injury to the brain
systemic painkillers
block pain no matter the source; usually opiates/narcotics that reward pathways of the brain meaning they activate the brain’s pleasure pathways, reducing the perception of pain
hyperpolarization of the pain centers in the central nervous system are not processed
ex: endorphins (endogenous) from FLATPEG
action potential
a wave of depolarization along or down a membrane (inside of the cell becomes more positive); all or nothing electrochemical response under normal circumstances - ions move! (once an AP starts it cannot be stopped!); only muscle and nervous tissue use RMPs to form APs
only occur in excitable cells; have a minimal stimulus (threshold potential); are “digital” or “all-or-none” responses; are self propagating chain reactions that occur without decrement
transmit signals over long distances; usually sodium and potassium; no summation
graded potential
determine whether or not an action potential is generated
barrage of EPSPs of sodium and potassium + IPSPs of chlorine; summation
summation
graded potentials between a resting membrane potential and threshold
EPSP
excitatory post-synaptic potentials
IPSP
inhibitory post-synaptic potentials
threshold
asks if EPSP + IPSP reach threshold
gap junctions (intercalated discs in cardiac muscle!)
PHYSICAL synapses; result in spontaneous depolarization due to cells being connected and sharing cytoplasms and ions
neurotransmitters
small molecules that can be rapidly synthesized and rapidly destroyed or removed from the synapse
examples: acetylcholine
process of release of neurotransmitters
- neurotransmitter is made in the soma of a neuron
- rotary proteins (dynein and kinesin) move vesicles from the soma to the pre-synaptic membrane
- action potential travels down the axon towards pre-synaptic terminal, causing a depolarization of the membrane
- depolarization causes the opening of voltage-gated calcium channels, allowing calcium in
- calcium forces the vesicle to fuse with the synaptic cleft, further releasing acetylcholine into the synaptic cleft through exocytosis
fate of neurotransmitters (after release)
- neurotransmitters can be enzymatically degraded: acetylcholinesterase can be inhibited by sarin nerve gas - acetylcholine levels go WAY up resulting in intense skeletal muscle contraction
- part of or all of the neurotransmitter can be taken up by re-uptake proteins on the pre-synaptic side: selective serotonin re-uptake inhibitors (SSRI) - serotonin levels go up in the brain slowly and only in the brain = “happier”
- sometimes neurotransmitters escape from the synapse and are usually scavenged by astrocytes
re-uptake inhibitors
selective serotonin re-uptake inhibitors (SSRI), serotonin re-uptake inhibitors (SRI), cocaine
selective serotonin re-uptake inhibitors (SSRI)
LEGAL blocks in the brain; antidepressants; take a long time to be effective (2-4 weeks)
serotonin re-uptake inhibitors (SRI)
methamphetamines that are ILLEGAL blocks all over the body; serotonin levels go up but production in the brain goes down (FEEDBACK INHIBITION); work very fast and is short term
what are two major “feel good” neurotransmitters?
serotonin and dopamine
cocaine
fast volted-gated channel blockers (local anesthetic) and a dopamine re-uptake inhibitor (dopamine levels in the brain go up)
neuronal circuits and pathways
convergent, divergent, reverberating, parallel after discharge
convergent neuronal circuits
input from many sources and/or nerves to a single source
example: it is time to get up in the morning
divergent neuronal circuits
input to many sources and/or nerves originating from one source
example: you want to flex your right bicep
reverberating neuronal circuits
repetitive
example: walking and breathing
parallel after discharge neuronal circuits
most complicated; represents different cognitive elements of your brain; its training, its experiences, and your brain’s formal education and assessment
example: cognition and figuring out a physics problem
vasoconstriction
narrowing of blood vessels, reduces blood flow and increases blood pressure
alpha-one adrenergic
resistance goes up
vasodilation
widening of blood vessels, increases blood flow and decreases blood pressure
alpha-two adrenergic
resistance goes down
SNAP and SNARES
allow for binding, fusion, and exocytosis of acetylcholine vesicles
botox
interferes with SNAP and SNARES: 1) mild paralysis of facial muscles that get rid of wrinkles and make one look younger and 2) botox can be a migraine headache prevention
where can we see areas of increased surface area in the brain?
dendrites and fissures
pre-frontal cortices
cognition, long-term memory, and personality
sulcus
depression that increases surface area; has a greater number of neurons that can be packed in the cerebral cortex
fissure
deeper and more prominent than a sulcus; increases surface area
corpus callosum
let’s hemispheres talk and communicate with each other
substantia nigra
basal ganglia structure located in the midbrain; a modulator for the pyramidal tracts which are the main pathways for voluntary movement being sent to the spinal cord; produces dopamine which helps fine tune movement signals sent by pyramidal tracts
parkinson’s disease and substantia nigra
a degeneration of dopamine producing neurons are lost in the substantia nigra which means pyramidal tracts can’t send out signals properly, resulting in impaired motor control (tremors + movement and balance are affected)
pyramidal tracts
of the midbrain and look like pyramids
limbic system
made up of the amygdala, mammillary bodies, the stria medullaris, and the ventral nuclei of gudden; interacts with the basal ganglia (if you see something scary)
known as the paleomammalian cortex
amygdala
plays a role in memory, decision making, and emotional responses
why is it important that we have an emotional response and brain rewiring when experiencing something scary?
displays our survival mechanism of fight or flight; it gets us ready to either face the threat or escape from it
speech formation and speech comprehension
on the LEFT brain the broca’s area is associated with speech formation and execution while wernicke’s area is associated with speech language comprehension and interpretation
hypothalamus
satiety centers (full) located in diencephalon (forebrain)
how many brain ventricles do we have?
four
cerebro-spinal fluid (CSF)
located in and around the brain and spinal cord as well as in the subarachnoid space between the arachnoid matter and pia matter within the ventricles of the brain; cushions the brain and provides nutrients; made by ependymal cells
cranium protects the brain, but what happens when there is trauma to the brain such as meningitis or encephalitis?
swelling occurs, but the brain has no where to go because of the cranium holding it in place leading to an increase in pressure
meninges
three layers that protect the brain and spinal cord: dura matter (outer layer), arachnoid matter (middle layer), and pia matter (inner layer); primary function is to protect the central nervous system (brain + spinal cord)
where does an epidural injection occur?
between L3 and L4
epidural block
procedure where local anesthetic is injected into the epidural space; works outside the dura matter to safely manage pain
hormones vs neurotransmitters
hormones stronger: numbers games (more numbers!)
hemodynamics (blood flow) that is sympathetic
blood flow increases to skeletal muscle and the brain but NOT to gastrointestinal tract and reproductive organs; when it comes to the skin it is dependent (do not want to bleed out vs heat and flushing)
basic gross anatomy of the spinal cord
cervical enlargement, conus medullaris, cauda equina, filum terminale, lumbar-sacral enlargement
cervical enlargement
many of these nerves are part of the brachial plexus
conus medullaris
end of the spinal cord: L2-L3 area
cauda equina
“horse tail” as they are long-reaching nerves that move inferiorly to other parts of the body
filum terminale
thin, fibrous band that connects the bottom of the spinal cord to the coccyx
pia matter that connects to the base of the sacrum; is a good source of cerebrospinal fluid which should be sterile HOWEVER, if there are white blood cells in the cerebrospinal fluid then that could signify meningitis
lumbar-sacral enlargement
widened area of the spinal cord that gives attachment to the nerves which supply the lower limbs; triangular bone at the bottom of the spine
gray matter
outside in brain but inside in spinal cord; consist of neuron cell bodies, dendrites and unmyelinated axons
white matter
inside in brain but outside in spinal cord; consist of bundles of myelinated axons
phrenic nerve
a spinal nerve that innervates the diaphragm for respiration; inhalation involves diaphragm and intercostal muscles
golgi tendon organs (GTOs)
proprioceptors that are located in the tendon adjacent to the myotendinous junction; detects stress
proprioception
body’s ability to ascertain body movements, direction and position awareness; when found in muscles, tendons, and ligaments they are known as mechanosensory neurons
is a sensory function, not motor function; however, motor nerves to muscles also contain some proprioceptive afferent fibers from those muscles
palsy
paralysis
neuralgia
pain that is distributed to one or more nerves
what are the cranial nerves?
olfactory I, optic II, oculomotor III, trochlear IV, trigeminal V, abducens VI, facial VII, vestibulocochlear VIII, glossopharyngeal IX, vagus X, spinal accessory XI, hypoglossal XII
olfactory nerve I (sensory)
special sense of smell
olfactory bulbs are larger in vertebrates that have a better sense of smell; proprioception (sensory function); smell and taste are linked and both are chemoreceptors; smell is linked to memory
consequences of lesions: inability to smell
optic nerve II (sensory)
special sense of vision
optic chiasm (part of the brain where optic nerves cross); vision centers are located in the occipital bone
consequences of lesions: blindness on the affected side
oculomotor nerve III (motor)
superior rectus, inferior rectus, medial rectus, and inferior oblique muscles involved; proprioceptive; parasympathetic to the sphincter of the pupil (constriction) and ciliary muscle of the lens (accommodation)
consequences of lesions: double vision, blurred vision, eyelids drooping (ptosis)
trochlear nerve IV (motor)
superior oblique muscle involved; proprioceptive; some of the smallest motor units (due to fine movements) are found within the muscles that control the eye
consequences of lesions: double vision; lens mineralize resulting in cataracts
trigeminal nerve V (sensory and motor)
mastication (chewing) mainly from mandibular branch (V3) consisting of masseter, temporalis, medial and lateral pterygoids
consequences of lesions: trigeminal neuralgia; intense pain along the course of a branch of the nerve; loss of tactile sensation in the face; weakness in biting or clenching jaw
what are the trigeminal nerve branches?
ophthalmic branch (V1): sensory input like touch, pain, and temperature from these regions
maxillary branch (V2): sensory input from the midface and upper oral structures
mandibular branch (V3): sensory input from the lower face and motor control of chewing muscles
abducens nerve VI (motor)
lateral rectus muscle involved; proprioceptive
consequences of lesions: double vision
facial nerve VII (sensory and motor)
controls facial expressions; proprioceptive
consequences of lesions: facial palsy known as a loss of taste sensation on the anterior two-thirds of tongue resulting in decreases salivation
vestibulocochlear nerve VIII (sensory)
special senses of hearing and balance
semicircular canals of the ear with fluid that play a role in balance and detection of acceleration and deceleration; cochlea plays a role in hearing
consequences of lesions: loss of hearing, loss of balance and equilibrium
glossopharyngeal nerve IX (sensory and motor)
sense of taste form posterior one-third of tongue
parasympathetic increases salivary gland secretion; motor to pharyngeal muscle; proprioceptive to pharyngeal muscle; amylase that breaks down starch
consequences of lesions: difficulty swallowing
vagus nerve X (sensory and motor)
goes all over the body; only nerve to extend beyond the head and neck to visceral organs in the thorax and abdomen
parasympathetic to sinoatrial (SA) node of the heart leading to heart rate lowering (SA node will fire twice per second without “vagal tone”)
consequences of lesions: difficulty swallowing and/or hoarseness
spinal accessory nerve XI (motor)
most posterior; motor to sternocleidomastoid and trapezius
consequences of lesions: difficulty elevating the scapula or rotating the neck
hypoglossal nerve XII (motor)
under the tongue; intrinsic tongue muscles that are entirely within the tongue + extrinsic tongue muscles that attach the tongue to other structures
what cranial nerve is MOST posterior in origin?
spinal accessory nerve XI
what cranial nerves are associated with vision and which are associated with double vision?
vision: optic nerve II
double vision: oculomotor nerve III, trochlear nerve IV, abducens nerve VI
motor unit size
dependent on how many muscle fibers are innervated to a neuron; size affects how fine the movements are for a group of muscle fibers
smaller motor units have less muscle fibers innervated; down to one
larger motor units have more muscle fibers innervated; up to thousands
why is there a need for such small motor units associated with the eye?
small motor units create finer motion and are used in eye muscles for small movements while helping in focusing sight
female brain vs male brain
female brain is better at multitasking, has an increase in corpus callosum, and an increase in synapse connections
primary motor cortex
anterior; controls the voluntary muscle movements
somatic sensory cortex
posterior; receives and processes sensory information from the body
what divides the primary motor and somatic sensory cortexes?
central sulcus
glial cells
central nervous system: astrocytes, microglia, oligodendrocytes, ependymal cells
peripheral nervous system: satellite and schwann cells
baroreceptors
detect changes in pressure; communicate with multiple brain centers to regulate blood pressure (medulla oblongata)
blood pressure is closely monitored by baroreceptors, which are located in key areas of the aortic arch and carotid sinuses
pre-capillary sphincters
function as smooth muscle structures that regulate blood flow into capillary beds
when they constrict, blood flow into the capillaries decreases, shunting blood to other areas or larger vessels; when they relax, blood flows freely into capillary beds, enhancing tissue perfusion
adrenergic influence
constriction of pre-capillary sphincters is primarily mediated by alpha-adrenergic receptors
adrenergic tone
refers to the baseline level of sympathetic nervous system activity, which heavily influences vascular tones
balance between vasoconstriction and vasodilation receptors determines blood vessel diameter
compound fracture
penetrates the skin
comminuted fracture
breaks into pieces
transverse bone fracture
perpendicular to medullary cavity
linear bone fracture
parallel to medullary cavity
oblique non-displaced bone fracture
diagonal to medullary cavity
oblique displaced bone fracture
diagonal and a “clean cut”
spiral bone fracture
leg is planted, but body has twisted severely
greenstick bone fracture
bone bends before breaking
*typically happens in the very young
layers of epidermis (superficial to deep)
stratum corneum, stratum lucidum, stratum granulosum, stratum spinosum, stratum basale
what layers of the epidermis are dead?
stratum corneum and stratum lucidum
what layers of the epidermis are alive?
stratum spinosum and stratum basale
what layer of the epidermis is moribund?
stratum granulosum
what are the five zones (regions) of the growth (epiphyseal) plate?
cartilage, proliferation, hypertrophy, calcification, ossification
cartilage
contains chondroblast
produced on the epiphyseal side of the plate as the chondrocytes divide and form stacks of cells
proliferation
hyperplasia: massive mitotic activity that increases cell number
hyperplasia
a lot of mitotic division = cell number goes up
hypertrophy
cells grow in size; one cells gets bigger
calcification
cells are filled with hydroxyapatite, then undergo apoptosis that leave the hydroxyapatite ONLY (cell is gone)
ossification
new diaphysis
what are the four hormones of bone remodeling?
parathyroid hormone, calcitriol, calcitonin, estrogen
parathyroid hormone (PTH)
from parathyroid gland; elevates blood calcium
stimulus: low blood calcium
osteoclast activity increases
calcitriol
activated vitamin D3; elevates blood calcium
osteoclast activity increases
ultraviolets rays from sun on skin for cholecalciferol - to liver for calciferone - to kidneys for calcitriol
calcitonin
from thyroid c-cells; lowers blood calcium
osteoblast activity increases, so hydroxyapatite production increases
osteoclast activity decreases
estrogen
prevents osteoblast apoptosis, keeping the osteoblast in circulation which is good for bone density
increased estrogen = increased osteoblast activity = building bone
decreased estrogen = menopause = osteoporosis
cardiac output formula
cardiac output = stroke volume x heart rate
ΔP (change in pressure) formula
ΔP = Q (flow) x R (resistance)
MAP (mean arterial pressure) formula
D + ((S - D)/3)
D = diastolic
S = systolic
pressure units = mmHg
what are the five prostaglandings?
PG I2, PG D2, PG E2, PG F2 alpha, PG H2
PG I2
wound stage two: vasodilation increases blood and increases ability to heal; inhibits platelet aggregation
PG D2
PAIN; pyretic (fire/heat) that promotes an increase in fever; sleep wake cycle
PG E2
PAIN; redness; swelling = increases inflammation
PG F2 alpha
corpus luteum (yellow body) regression
estrogen and oxytocin stimulate the release of oxytocin, which aids in he stimulation of uterine contraction
PG H2
initial wound stage: thromboxane - 1) vasoconstrictor and 2) promotes platelet aggregation to form clots
we do not want to endure blood loss
which prostaglandin is major in inflammation?
PG E2
