T's test review Anatomy 1

sympathetic nervous system

(fight or flight) (thoracolumbar division): its preganglionic nerves arise from the thoracic & lumbar spinal cord. -Activated during exercise, excitement, and emergencies -also called the thoracolumbar division length of preganglionic fibers: short, releases ACH & binds to nicotinic recepotrs length of postganglionic fibers: long & releases nor/epinephrine branching of axon: highly branches (influences many organs) location of ganglia: close to spinal cord symp & parasymp have opposite effects in organs, and are controlled by the hypothalamus.

parasympathetic

(restful & calm) (craniosacral division): because its preganglionic nerves come from the cranial nerves and also from the sacral regions. Concerned with conserving energy also called the craniosacral division length of preganglonic fibers: long, releases ACH & bind to nicotinic receptors length of postganlonic fibers: short, releases ACH & binds to muscarinic receptors branching of axons: few branches, localized effect location of ganglia: near its visceral effector organ symp & parasymp have opposite effects in organs, and are controlled by the hypothalamus.

Unique characteristic of CT

-All have common embryonic origin: all arise from mesenchyme tissue as their tissue of origin -Have varying degrees of vascularity (cartilage is avascular, bone is highly vascularized) -Cells are in extracellularmatrix (ECM) (ground substance + Fibers) •Matrix supports cells so they can bear weight, withstand tension, endure abuse

types of proprioceptors

-Golgi tendon organs (GTO): found in tendons, & are stimulated when the associated muscle contracts & thus stretches the tendon. GTO works closely w muscle spindles.The contracting muscle stimulates the GTO and the GTO feeds back to inhibit further muscle contraction (prevents injury) -Muscle spindles: found in the belly of the skeletal muscles (especially the arms & legs) & tell us when the muscles are stretched.

For a muscle to return to a resting state:

-Oxygen reserves are replenished -Lactic acid is reconverted to pyruvic acid -Glycogen stores are replaced -ATP and creatine phosphate reserves are resynthesized all require extra O2; excess post exercise oxygen consumption

types of fractures

-Position of bone ends after fracture Nondisplaced: ends retain normal position Displaced: ends are out of normal alignment -Completeness of break Complete: broken all the way through Incomplete: -not broken all the way through; Whether skin is penetrated Open (compound): skin is penetrated & damage to surrounding tissues Closed (simple): skin is not penetrated -based on trauma Greenstick: A partial fracture in which one side of the bone is broken, but the other side has only bent. Happens more in children because their bones are less calcified. Comminuted: 2 or more intersecting breaks create several separate bone fragments (crushed bones) Spiral: the bone is usually twisted apart impacted: the broken ends of a bone are forced into one another. Many bones fragments may be there. pathologic: due to an underlying disease, i.e, cancer or osteoporosis. Stress fracture (hairline fracture): a partial fracture due the body's inability to withstand repeated stress. 25% involves the distal third of the fibula.

root vs rami

-Roots lie medial to and form spinal nerves •Each root is purely sensory OR motor -Rami lie distal to and are lateral branches of spinal nerves •Can carry BOTH sensory and motor (mixed nerves).

characteristics of graded potential

-Short-lived -Taking place over short distances -Slight depolarization or hyperpolarization not reaching the threshold point -Strength of a graded potential varies w the strength of the stimulus -Current flow decreases w distance from the stimulus

occipital lobe

-The primary visual cortex is located here. -Retinal images are interpreted here.(vision). -The visual association areas interpret what is seen, and enable the thinking cerebrum to use the info. Imagine looking at a clock. Seeing the clock is far different from being able to interpret it.

endochondral ossification

-bones form from within a model hyaline cartilage -Almost all bones of the body from the base of the skull down (except the clavicles) are formed by this method. -starts w/ primary ossification center @ shaft, long bones have 2nd center @ epiphyses process: 1.The perichondrium cells differentiate into osteoblasts. These osteoblasts deposit bone matrix. Bone collar forms around diaphysis of the hyaline cartilage model 2.Chondrocytes in the center of the shaft began to die, their matrix is calcified, leaving cavity in the diaphysis. 3.Periosteal bud (blood vessels, nerves, osteoblasts, and osteoclasts ) invades cavities, leading to formation of spongy bone by osteoblasts at a primary ossification center. 4.Bone formation then spreads along the shaft toward both ends. Diaphysis elongates, and medullary cavity forms. Blood vessels and osteoblasts migrate into the epiphyses, creating secondary ossification centers. 5.Epiphyses ossify (epiphyses are filled with spongy bones). Hyaline cartilage remains only in epiphyseal plates and articular cartilages.

upper motor neuron

-cell body are located on the precentral gyrus (primary motor cortex) -Its axon then runs down the brain and at the level of medulla oblongata becomes spinal cord -The fibers cross over, known as "decussates", to the opposite side, enters the spinal cord and runs down the spinal cord in the corticospinal tract (a collection of axons travels between the cerebral cortex & the spinal cord) - Eventually, it synapses w the dendrites of a lower motor neuron in the ventral horn or the dendrites of an interneuron in the gray matter.

Action Potential (AP)

-electrical signal, nerve impulse, nerve firing (all the same term) produced by neurons -sequence of rapidly occurring events that decrease or reverse the membrane potential & eventually restore it to the resting state. -taken place in axon a massive momentary reversal of a neuron's membrane potential from about -70 mV to about +50 mV inside of membrane becomes LESS NEGATIVE` than resting membrane potential (moves toward zero or above) then the probability of producing impulse increases.

brachial plexus

-formed by C5-C8 & T1, very complex -supplies all nerves to the arms. Injury to brachial plexus cause weakness or paralysis of the arm. "Friday night palsy".

CT elements

-ground substance (gel material that fills space bt. cells, solutes can diffuse through here) made of adhesion protein, sugar protein, water -fibers (collagen, elastic, reticular) -cells ("blast":immature cell secreting ground substance and "cyte": mature cells)

cranial bone

-have foramina/holes for passage of nerves and blood vessels -cavity enclosed by cranium -opening at foramen magnum where spinal cord enters -cranial brain and brain tissues separated by meninges

autonomic nervous system

-in PNS under efferent NS carries info. to smooth muscles, glands, & cardiac muscle divisions: sympathetic nervous system: flight or fight response parasympathetic: for rest

somatic nervous system

-in PNS under efferent diviosn caries info. to sk. muscle (voluntary NS)

intramembranous ossification

-in flat bones process: 1. Primary ossification centers are formed when MESENCHYMAL cells (Undifferentiated embryonic CT) cluster and differentiate into OSTEOBLAST. 2. Osteoblasts secrete OSTEOID (organic materials) which calcifies. Trapped osteoblasts become OSTEOCYTE 3. Early spongy bone is formed when osteoid is laid down around blood vessels by osteoblasts, resulting in trabeculae. Mesenchymal cells surrounding the bone become periosteum. Vascular tissues become bone marrow 4. Early compact bone is formed.

electrical synapes

-less common than the chemical synapses. -APs conduct directly bt the plasma membranes of adjacent neurons thru gap junctions. Advantages: 1) faster communication 2) synchronization (coordination). Mediated via gap junctions bt adjacent neurons. Ex., in areas of the brain that control jerky movements of the eyes.

unicellular exocrine glands that are glandular epithelial

-mucous and goblet cells both produce mucin for protection

fibrous tunic

-outermost layer -no blood capillaries -where optic nerve leaves the eye key structures: -thickest layer= sclera/ white of eye -continuous w/ dura mater of brain -anchors extrinsic eye muscles cornea= -clear front w/ no blood capillaries, --has sensory nerve endings -gives shape to eye -first part of eye to bend light -covers iris and pupil

calcitonin

-released from thyroid gland. -stimulates Ca deposition from the blood into the bones. -lowers blood calcium level.

diencephalon structures

-thalamus: all sensory& motor impulses pass thru it on their way to & from the cortex. It is a RELAY station where "editing" of the signals occur. It is a gateway to the cerebral cortex. i.e, signals for taste, smell, hearing, equilibrium, emotion pass thru the thalamus. -pineal gland: produces melatonin, involved w your biological clock and induces sleep. -hypothalamus: The main VISCERAL control center of the body. Is the major control center of ANS & endocrine system. regulator of: homeostasis, and controls hunger, thirst, body temp, emotions, sexual response. -pituitary gland: called the "master gland". It makes 7 hormones & stores 2 others that were made by the hypothalamus. There is anterior & posterior pituitary regions. It is connected to the hypothalamus via a stalk

arachnoid layer

-the middle layer, loose cover that does not dip into the sulci. -It is separated from the dura mater by the subdural space. -Below the arachnoid is the subarachnoid space. It is filled w the SCF. It also contains the largest blood vessels serving the brain. The arachnoid villi extends into the dural sinuses & rebsorbs CSF back into venous blood.

thyroxine

-thyroid gland hormone. -adjusts GH activity -Low thyroxine production leads into low growth.

types of bone cells

.Ostegenic cells AKA osteoprogenitor cells: -STEM cells (unspecialized) of the bones, are Mitotic. -in the inner lining of periosteum & endosteum, and Volkman's canals. -differentiate into osteoblasts. Osteoblasts: -no mitotic activity -Secrete mineral salts and organic materials for the bone build up (deposit bone matrix). -become osteocytes. Osteocytes: -mature bone cells, non-mitotic -Came from osteoblasts -They maintain bone ECM Osteoclasts: -bone breaker cells. -Found on the bone surface. -Derived from a form of monocyte-macrophage -Involved in BONE RESORPTION (breakdown the bone ECM). -Postmitotic.

temporal summation

1 or more presynaptic neuron fires rapidly, if the effects of the 1st depol haven't disappear before the 2nd hits, the second builds (summate) on the first & further depol the postsynaptic neuron. 2. large # of presynaptic neurons converge on the postsynaptic neuron, so many receptors are simultaneously stimulated by the neurotransmitter & it creates a large EPSP

Na+/K+ antiporters vs voltage gated NA+ channel

1) Voltage-gated Na+: is only specific to Na+ ions. 2) Voltage-gated Na+ is a voltage-gatedchannel whereas the previously described Na+/K+ antiporter was a CHEMICAL channel. 3)Activation of the voltage-gated Na+is required for generation of the AP whereas the activation of Na+/K+ channel is responsible for generation of END PLATE POTENTIAL

action potential characteristics

1. Brief 2. large depolarization of the membrane potential (going from -70mM to +30 mV). 3. the intensity of an AP does NOT decrease w distance from the stimulus. 4. AP ONLY happens in the axons of neurons, skeletal muscle, and cardiac muscle cells.

CT types

1. CT proper -lose proper: areolar, adipose, reticular -dense proper: dense regular, dense irregular, elastic 2. specialized CT -blood -bone -cartilage (hyaline, elastic, fibrocartilage) (Avascular)

4 regions of the brain

1. Cerebral hemispheres 2. Diencephalon 3. Brain stem (midbrain, pons, medulla) 4. Cerebellum

ascending pathway neuron orders

1. First-order neuron -Conducts impulses from cutaneous (skin) receptors and proprioceptors -Branches diffusely as it enters spinal cord or medulla -Synapses with second-order neuron second order -Interneuron -Cell body in dorsal horn of spinal cord or medullary nuclei -Axons extend to thalamus or cerebellum third order -Also an interneuron -Cell bodies in thalamus -Axon extends to somatosensory cortex -No third-order neurons in cerebellum

brain lobes

1. Frontal 2. Parietal 3. Occipital 4. Temporal 5. insula

Types of seizures

1. Grand mal (tonic-clonic seizure): features a loss of consciousness & VIOLENT muscle contraction. Falling to the ground. 2. petit mal (absence seizure): -the individual suddenly stops conscious activity & is unaware of her surrounding. -It may last a few sec to min. The person may just stare, eyelids flutter, or twitching of facial muscles. The individual then starts his normal routines. 3. Status epilepticus: Prolonged or continuous seizures w/o any break and can be life threatening, as it can disrupt respiration, induce hypoxia and brain damage.

epithelial cells in taste buds

1. Gustatory epithelial cells: taste receptor cells have microvilli called gustatory hairs that project into taste pores, bathed in saliva •Sensory dendrites coiled around gustatory epithelial cells send taste signals to brain 2. Basal epithelial cells: dynamic stem cells that divide every 7-10 days. For example drinking hot soup destroys the taste buds and the stem cells replace the damaged taste buds.

function of skeletal muscle

1. Movement (voluntary) 2. Posture maintenance & support: muscle tone maintains upright posture. 3. Producing heat to help maintain body temp. In fact, the heat generated by normal muscle tone is about 25% of the total body heat at rest. During exercise, of course, heat production increases.

structural classification of neuron

1. Multipolar: 3 or more processes, most abundant 2. Bipolar: 2 processes 3. Unipolar/ pseudounipolar: single short process originated from the cell body forming a T-shaped processes. Found in the dorsal root ganglia of the spinal cord. The 2 branches function as a single axon. Most sensory neurons are pseudounipolar.

Action Potential process

1. Na+ gates in the membrane are opened @ AP, hence, Na+ moves inside the cell. Thus, the potential difference across the cell membrane changes (move toward zero, i.e, from -70 mV of the resting potential toward 0 mV referred to as DEPOLARIZATION). 2. At this point, the Na+ gates, active channels, shut close and the K+ gates, active channels, open. These K+ gates push the outflow of K+. That is K+ moves outside the cell and this action leads to inside the cell becoming negative. This is the REPOLORIZATION step. Repolarization resets electrical conditions, not ionic conditions. There is a lot of Na+ still inside the cell. Another active channel called NA+/K+ PUMP (Na+/K+ ATPase) gets activated to pump Na+ out (3 molecules of Na+) and to pump back in K+ (2 molecules of K+) to restore ionic conditions & stabilize the negativity of the resting membrane potential. 3. The membrane potential drops to its original resting stage of -70mV & it even undershoots the resting membrane potential a bit (due to longer staying open of the K+ channels)called HYPERPOLARIZATION before balancing out at its normal -70 mV. 4. Resting state: all gated Na+ & K+ channels are closed, only leakage Na+ & K+ channels are open. after the absolute ref. period when most Na+ channels have returned to their resting state. The threshold for another AP is much higher than the normal but a strong stimulus can fire another AP. neuron receives many graded potentials via its dendrites (AP only happens in axons). If the stimulus is strong enough then at a region called the trigger zone (located roughly at the end of the soma and the axon hillock), an AP emerges & travels in milliseconds down the axon. That's why anesthetics act to prevent the emergence of an AP so you don't feel the pain during the surgery. Novocaine blocks the opening of voltage-gated Na+ channels. Cold (ice application to injury) slows propagation of Aps & interrupts blood circulation & delivery of oxygen to neurons.

muscle types

1. Skeletal: voluntary&striated muscles. The striated pattern (stripes) is the result of precise arrangement of the contracting proteins within the muscle cells. Skeletal muscles are attached to the bones and supplied by the motor nerves, thus move the skeleton. An exception is diaphragm that doesn't move the bones but enlarges the thoracic cavity. Sometimes skeletal muscle act involuntary. For example, shivering due to a cold temperature. 2. Smooth muscles: involuntary, in the walls of the intestine, blood vessels, and uterus. They have no striation. They have a single nucleus. Visceral organs contain smooth muscle cells. 3. Cardiac muscles: not voluntary, have striation, Cardiac muscle as a whole is called the MYOCARDIUM. The contraction of myocardium creates blood pressure so the blood circulates in the body. Cardiac muscle cells have the ability to contract by themselves.

Action potential of muscle contraction

1. The motor neuron fires and an AP comes down the axon fiber to the axon terminal. 2. As a result of this AP, Ca++ channels located in the membrane of the axon terminal open which leads to uptake of the Ca++ by the motor neuron axon. 3. Elevation of Ca++ inside the axon causes the synaptic vesicles that are full of the neurotransmitter Ach to move to the tip of the axon & release Ach into the synaptic cleft. This is the cleft between the motor neuron and the muscle that the neuron innervating. This synaptic cleft is 20 nm in diameter. 4. The released Ach binds to the Ach-receptors on the sarcolemma (cytoplasmic membrane) of the muscle fiber. 5. This opens a singlechemical gate (channel) of Na+/K+ antiporter on the postsynaptic muscle fiber membrane. Thus Na+ ions moving in and K+ ions moving out through this single Na+/K+ channel. 6. Since more Na+ entering than K+ exiting the channel, a local change in the postsynaptic membrane potential called the end plate potential is produced. Ach is quickly destroyed by acetylcholinesterase. 7. Na+ ions pours in and this causes the depolarization, that is, the resting potential of the muscle membrane drops from -90 mV to about -50 mV. If this end plate potential generates enough change in membrane voltage to reach threshold, voltage-gated Na+channels in membrane will open. Large Na+ influx leads to a muscle AP that spreads in all directions in the targeted muscle. 8. repolarization follows the depolarization. This is done by the closing of the voltage-gated Na+ channels and opening of the K+-gated channels. Thus, K+ (positive ion) is rapidly moved out of the muscle and the inside of the membrane becomes negative and the resting membrane potential is established. Please note that this muscle AP (depol & repol) is extremely fast (1-2 milliseconds duration). 9. This waves of AP moving down the T tubules, activates (opens up) Ca++ channels located on the sarcoplasmic reticulum (SR). Stored Ca++ in the SR is released inside the cytoplasm of muscle fibers. Ca++ release from SR leads to contraction. AP is brief & ends before contraction is seen. 10. This free Ca++ combines with troponin, a regulatory protein. Troponin changes shape and moves tropomyosin, another regulatory protein, away from myosin-binding sites. 11. Myosin heads is then allowed to bind to actin, forming cross bridge. •Cycling is initiated, causing sarcomeres hortening and muscle contraction action potential that is propagated along the sarcolemma & into the T tubules is the excitation step. This was the electrical event. Excitation step then couples to the contraction step (mechanical event) described by the theory of sliding of the filaments. The entire event is thus called excitation-contraction coupling.

knee joint

1. Two ligaments on the outside of the knee and are called lateral & medial collateral ligament 2. Two ligaments within the knee and are called anterior & posterior cruciate ligaments. 3. Two menisci (meniscus....lateral & medial): C-shaped thin cartilage bt the femur & the tibia. Are prone to injury 4. Bursa: means purse. Sac of synovial fluid bt the joint & the tendons that cross over the joints. -Bursa permits the tendons to slide easily as the bones are moved. Bursa are made of tougher outer connective tissues but lined w the synovial membrane 5. Tendon sheaths: covers tendons.

spinal cord function

1. a conduit for the motor functions that runs down the spinal cord. 2. a conduit for the sensory neurons that travels up the spinal cord 3.a center for certain reflexes referred to as spinal reflexes.

The lens & its suspensory ligament divide the eyeball into 2 segments:

1. anterior segment 2. posterior segment

supporting cells in CNS

1. astrocytes: the most abundant cells in the CNS: help exchanges bt capillaries & neurons. 2. microglia: are resident macrophages of the brain, defensive cell 3. ependymal cells: they line the central cavities of the brain and the spinal cords, line cerebrospinal fluid cavities 4. oligodendrocytes: They wrap the processes of the thick neurons forming myelin sheaths.

Characteristics of epithelial cells

1. cellularity: made up of packed cells 2. specialized junctions: desmosomes & tight junctions 3. cell polarity: apical vs. basal surfaces 4. avascularity, but innervated 5. high regeneration rate 6. supported by underlying connective tissues

2 Body Cavities

1. dorsal (cranal & vertebral) 2. ventral (thoracic & abdominal)

dorsal ramus

1. dorsal ramus (supply posterior body trunk) -supply the skin & muscles of the back. -Each branch innervates a strip of muscle and skin in line with where it emerges from spinal cord 2. ventral ramus (supply rest of trunk and lims) all ventral rami except for T2-T12, join one another lateral to the vertebral column to form 4 nerve plexi (interlacing nerve networks). The 4 somatic nerve plexi are: cervical, brachial, lumbar, & sacral plexi. In the thoracic area where they don't form plexi, it becomes the intercostal nerves supplying the muscles bt the ribs and the skin overlying them. Only ventral rami form plexi. 3. meningeal branch all have mixed nerves

stages of sleep

1. eyes are closed, you become drowsy, muscles relax, mind stops racing, breathing slows down, ALPHA waves become slower and more in sync. If stimulated we immediately wake up. This is about 10 min. then you begin entering stage 2. EEG becomes more irregular, becoming more relaxed. "sleep spindles"or BURSTS of APLPHA waves activity with high amplitude appear in the EEG. Arousal is more difficult. About 20 min. 3. sleep deepens, and the EEG shows THETA & some DELTA waves. Stages 3 & 4 are difficult to distinguish becuz they differ only in degree. Skeletal muscles are very relaxed, and dreaming is common. Most nightmares are here. 4. The EEG appears mostly DELTA waves. Vital signs (HR, bp, respiratory rate) at their lowest. Arousal is difficult, this is where sleepwalking, bedwetting occurs 5. REM

tunics/layers of eye

1. fibrous tunic 2. vascular tunic 3. sensory tunic

fracture repair

1. hematoma formation -blood vessels break, causing a fractured hematoma (blood clot) @ fracture site -bone cells fed by vessels die -swelling % pain 2. formation of fibrocartilaginous/ soft callus -capillaries from periosteum grow into hematoma and phagocytize fracture debir -fibroblast from periosteum secretes collagen fibers to connect broken ends -osteogenic cells from endosteum become chondrocytes secrete hyaline cartilage hyaline cartilage + collagenous CT = soft tissue 3. bone callus formation -osteoblast from periosteum lay down collar of spongy bone (bone callus) -bony callus hardens -ends of fracture held in place & withstand stress and muscle contraction 4. remodeling of callus -bone callus is remodeled -spongy bone is resorbed & replaced w/ compact bone -thickened area @ fracture site

factors that affect bone growth and maintenance

1. heredity 2. nutrition 3. hormones (GH promotes growth of bones, sex hormones promote closure of epiphyses of long bones) (growth stops). 4. exercise. It means bearing weight. Without this stress, bones lose calcium faster than it is replaced.•(growth stops for F bt 14-19 & for M bt 16-21 years old).

types of ion channels

1. leaks channels (nongated): always open. Typically more K+ leak channels than Na+ leak ones. 2. chemically-gated channels: open & close in response to the binding of a ligand (i.e, hormones, neurotransmitters, certain ions) 3. mechanically-gated channels: open/close in response to sound, touch, pressure. 4. voltage-gated channels: opens in response to a change in the membrane potential.

2 Types of epithelial functions

1. linings 2. glandular for secretions (endocrine & exocrine)

Fissure types

1. longitudinal: deep line divings L & R hemisphere 2. transverse: separates cerebral hemisphere from cerebellum

functional area of cerebral cortex

1. motor area 2. sensory area 3. association area

structures in hair

1. nerve ending 2. sebaceous gland: makes sebum to prevent drying 3. Eccrine (watery) and apocrine (milky) sweat glands 4. arrector pili: gives goose bumps

types of transport through a cell membrane

1. passive transport (simple diffusion, osmosis, facilitated diffusion, filtration- need mechanical E) -no E used by cell 2. Active transport: Requires E -via pump (ex. Na pump in nerves) -via vesicles (endocytosis, exocytosis, transcytosis)

grey matter

1. posterior (dorsal) root & rootlets contain only sensory axons, which conduct nerve impulses from sensory receptors in the skin, muscle, internal organs into the CNS. 2. The anterior (ventral) root & rootlets contain axons of motor neurons, which conduct nerve impulses from the CNS to effectors (muscles & glands). 3. lateral horns: cell bodies of the autonomic nervous system (ANS). It is present only in the thoracic & upper lumbar segments. 4. Gray comissure: this connects the left & right halves of the gray matter.

neurons in ANS

1. preganglionic neuron: its soma is in the brain stem or the lateral horn of the spinal cord (that means its soma is w/in the CNS). The preganglionic axon runs out to an autonomic ganglion outside the CNS. This latter ganglion is where the soma of the postganglionic neuron is located. -pass through white rami communicantes and enter sympathetic trunk (chain) ganglia -lightly myelinated 2. postganglionic neuron: sends its axon out to the effector organs or smooth muscle (i.e, smooth muscle cells in the blood vessel walls) -enter ventral rami via gray rami communicantes -nonmyelinated **Ach is neurotransmitter bt the two neurons**

Nervous system function

1. sensory input 2. integration 3. motor output

3 regions of cerebral hemisphere

1. superficial cortex of gray matter 2. internal white matter. deep to the gray matter 3. basal nuclei are paired masses of gray matter w/in the white matter, deep deep deep inside the brain, lateral to the thalamus. Involved in subconscious aspects of voluntary movements. In both Parkinson's patients and Alzheimer's, basal ganglia (nucleus) degenerates.

5 basic taste bud quality

1. sweet (like sugar) •2. sour (acid, lemon) •3. salty (salt) •4. bitter (caffeine)• 5. umami (grilled meat taste) some area of the tongue are more sensitive to certain qualities than others: Tip of the tongue: sweet & salty Sides of the tongue: sour back of the tongue: bitter.

joint classification by function

1. synarthrosis: is immovable joints. Example: a suture bt 2 cranial bones where collagen fibers from one bone penetrates the adjacent bone. 2. amphiarthrosis: slightly movable. Two bones are joined by cartilage. Example: symphysis joint bt adjacent vertebrae 3. diarthrosis: freely movable joint. This is the largest category of joints. Example: all the ball-and-socket joints. All diarthrosis are synovial joints.

force generated by a muscle to cause contraction is increased by..

1. temporal summation 2. motor unit recruitment

contractile myofilament proteins

1. thick filament: myosin 2. thin filament: actin, tropomyosin, troponin sliding of thin filament past the thick filaments produces muscle shortening

other types of CT

1. white blood cells 2. macrophage 3. mast cell (for inflammation) 4. fat cells

cross bridge cycle

1.Cross bridge formation: high-energy myosin head attaches to actin thin filament active site 2.Working (power) stroke: myosin head pivots and pulls thin filament toward M line 3.Cross bridge detachment: ATP attaches to myosin head, causing cross bridge to detach 4.Cocking of myosin head: energy from hydrolysis of ATP "cocks" myosin head into high-energy state•This energy will be used for power stroke in next cross bridge cycle

function of skeleton

1.Support: framework that supports the body. 2.Protection: protecting brain, heart, & lungs. 3.Movement. 4.Storage for Ca++ & phosphate. 5.Site for hematopoiesis

alterations of skin color

1.cyanosis: blue skin. Due to poor Hb of the RBCs oxygenation. 2.Erythema: red. Increased blood flow to the skin. Due to inflammation & blushing. 3.Pallor: pale. Due to anemia, low blood flow (cold), low blood count or low blood pressure. 4.Jaundice: yellow. Accumulation of bilirubin in skin. In newborns due to immature liver metabolism or traumatic delivery (the baby may be bruised, and as the blood in the bruise breaks down, bilirubin is formed). 5.Bronzing: Addison's disease (decreased activity of the adrenal glands). Too much ACTH from the pituitary gland in a fruitless attempt to stimulate the adrenal glands to release cortisol, also stimulates melanocytes to release melanin which causes darkening of the skin 6.Bruise: Due to broken blood vessels.

# of cranial and spinal nerves in PNS

12 pairs in cranial 31 pairs is spinal

degrees of burns

1st degree: removal of epidermis 2nd: removal of epidermis and dermis 3rd: removal of epidermis, dermis, and subcutaneous layer

basement membrane

2 layer membrane between epithelia and CT -basal lamina is layer secreted by epithelial cells -rectal lamina is layer secreted by CT

dermis

2. Dermis/ superficial fascia -papillary layer: loose areolar CT, gives rise to finger prints -reticular layer: dense irregulatr -form lines of cleavage/ tension/ langers lines from collagen fibers running parallel to skin surface

How many bones are in the human body?

206 bones

dynamic equilibrium

3 semicircular canals in the inner ear; one for ea plane of the body (horizontal, medial, sagittal). W/in ea semicircular canal is small ridge (the crista ampullaris) that is associated w hair cell receptors. The CRISTA AMPULLARIS itself is a cone-shaped structure, covered in receptor cells called "hair cells". Covering the crista ampullaris is a gelatinous mass called the CUPULA Upon angular acceleration (rotation), the endolymph within the semicircular duct deflects the cupula against the hair cells of the crista ampullaris. The hair cells respond by stimulating neurons that innervate them. When the head is rotated to one side, the fluid in that canal swishes over the crista & causes the hair cells to fire. Once again, the vestibulocochlear nerve brings this input to the brain, & we interpret it as spinning in a certain direction. MOVING FLUID within the canal ducts is one cause of DIZZINESS. After a person spins around, the fluid within the canals continues to MOVE OVER CILIA after the spinning stops, giving the sensation that the spinning is still happening.

rigor mortis

3-4h after death & peaks 12h postmortem, cell membranes become leaky. Ca2+ leak out of the SR into the sarcoplasm & allow myosin heads to bind to actin. ATP synthesis stops shortly after breathing stops, so Ca++ cannot be pumped back into SR. ATP is also neededfor cross bridge detachment. cross-bridges cannot detach from actin. Thus, muscles are in a constant state of contraction called rigor mortis. After ~24h, rigor mortis disappears as the proteolytic enzymes from lysosomes digest the cross-bridges.

sensory tunic (retina)

3rd innermost layer -where cones and rods are located (visual receptors) -made of superficial pigmented layer and neural layer -optic nerve enters back of retina @ optic disc where blood vessels supply retina

# of skull bones

8 cranial , form the brain case lined w/ meninges 14 facial bones forming face and jaw

Parkinson's disease

A disorder of the central nervous system that affects movement, often including tremors. motor system disorder. Affects people in their 50's & 60's. Dopamine-releasing neurons in the substantia nigra of the brain stems are the targets. Trembling in hands, jaws, arms, legs, stiffness of the limbs & trunk, shuffling walk, bradykinesia (slow movement) .•The tremors lessens w voluntary movements (that is when they go to pick up something). This is opposite to what is seen in tremors related to cerebral injury (tremor gets worst as they get closer to their intended target). LDOPA (Dopamine) is given to treat

energy needed for muscle contraction

ATP supplies the energy needed for the muscle fiber to: -Move and detach cross bridges -Pump calcium back into SR -Pump Na+ out of and K+ back into cell after excitation -contraction coupling ATP is the only source of energy for contractile activities; therefore it must be regenerated quickly ATP produced by 1. aerobic respiration. This is mainly via cellular respiration and ATPs are produced inside the mitochondria and the process requires oxygen. •2. anaerobic: when oxygen isnt there. Only glycolysis generates ATPs and is followed by fermentation (lactic acid formation) .•3. Direct phosphorylation of ADP: using creatine-phosphate stored in muscles that donates a P to ADP to instantly form ATP.

important points on muscle

All muscle cell can only contract. It means that they shorten and pull the bone to produce movement. Muscles can't push because when they relax they exert no force. •Muscle is different than muscle cells. Each muscle is made up of thousands of individual muscle cells which also may be called myocytes or muscle fibers .•Depending on the ork a muscle required to do, variable numbers of myocytes will contract. i.e, less myocytes contract when lifting a feather as opposed to lifting a book.

aponeurosis

CT connection is like a sheet. -any contraction of muscle pulls on attached bone

ligament

CT joined bt bones

cones vs rods

Cones- color, abundant in center of retina, especially in FOVEA IN MUCULA LUTEA (only has cones) Rods- black and white -detect presence of light -abundant at edge of retina -rods used at night -more common than cones contain a visual pigment called rhodopsin. no rods or cones @ blind spot When light strikes the retina, the rods & cones generate graded potentials & NOT AP. AP is generated by ganglion neurons, which all converge at the optic disc and pass thru the wall of the eyeball as the optic nerve. In other words, axons of retinal ganglion cells form optic nerve. imbalances: •Night blindness: when there is a problem w rod function, so you are unable to see in dim light. •Color blindness: happens if one or more types of cones are missing because of a genetic disease. If red & green cones are missing, you get red-green color blind ness.

Sound pathway through ear

Differences in frequency are heard as different pitches....the higher the frequency, the higher the pitch. The deflection of the hair-cell stereocilia opens mechanically gated ion channels that allow any small, positively charged ions (primarily potassium and calcium) to enter the cell. The influx of positive ions from the endolymph in Scala media depolarizes the cell, resulting in a receptor potential. This receptor potential opens voltage gated calcium channels; calcium ions then enter the cell and trigger the release of neurotransmitters at the basal end of the cell. The neurotransmitters (it is thought to be glutamate) diffuse across the narrow space between the hair cell and a nerve terminal, where they then bind to receptors and thus trigger action potentials in the vestibulocochlear nerve. In this way, the mechanical sound signal is converted into an electrical nerve signal. Sound waves enter the external auditory canal & strike the tympanic membrane, causing it to vibrate. The tympanic membrane transfers the motion to the malleus, which transfers it to the incus, which transfers it to the stapes. (the ear ossicles actually amplify the motion of the tympanic membranes). The stirrup of the stapes is connected to the oval window in the cochlea, and the vibration sets the perilymph fluid in the scala vestibuli in motion. The motion continues down the scala vestibuli to the tip of the cochlea, rounds the corner, then returns through the scala tympani until the energy is released out the round window & back into the middle ear cavity. As the perilymph in the cochlea moves, it makes the basilar membrane move & tweek the hair cells touching the tectorial membrane. This tweeking causes the hair cells to release neurotransmitters (believed to be glutamate), and an action potential is created at the nerve level & sent down the vestibulocochlear nerve to the brain. •Hair cells in different parts of the organ of corti are sensitive to different frequencies (pitches) of sound. Hair cells near the oval window are sensitive to high pitch sounds, while those near the tip are sensitive to low pitch sounds

Osmosis

Diffusion of water from high to low concentration of H2O through a selectively permeable membrane -passive diffusion

diverge

Divergence allows impulses to spread out into more than one pathway. less presynap. that post

optic CHIASMA

Each eyeball is attached to an optic nerve, & the 2 optic nerves meet at the OPTIC CHIASMA where some of the nerve fibers cross over to the other side. The optic tracts then continue onto the visual cortex of the brain where the visual input is interpreted. Medial fibers cross at the chiasma, laterals stays on the same side. So each optic tract contains fibers from the ipsilateral lateral (temporal) retina & the contralateral medial (nasal) retina. So each visual cortex in the brain receives information from both eyes.

limbic system

Emotional brain. It has its components in the cerebrum & diencephalon there is a limbic system in ea. hemisphere Important center for emotion (rage, fear, sex drives, feelings, etc) as well as memory & learning& executive function. components: cingulate gyrus, amygdala, hippocampus, hypothalamus

structure of nerve

Endoneurium (a loose connective tissue layer that encloes axons & their myelin sheaths) perineurium (a coarse connective tissue that bundle nerve fibers into fascicle Epineurium (tough fibrous sheath around all fascicles to form the nerve.

ependymal cells

Ependymal cells synthesize the CSF. CSF acts as a shock absorber.

Epidermis

Epidermis (dead cells arise to surface, avascular) -stratum basale= base layer, mitosis of new cells stratum corneum= dead cells w/ keretin -has keratinocytes, dendritic cells, melanocytes, merkel cell aka sensory cell 3. Hypodermis (not part of skin) -deep facia -adipose tissue

muscle tone

Except during certain stages of sleep, most of our muscles are in a state of slight contraction called muscle tone. •Muscle tone helps our support & posture. Think about sitting upright at your desk, muscle tones of your back & neck keeps a healthy posture. Exercise improves muscle tone. Both isometric & isotonic improve muscle tone.

cerebral cortex

Function: conscious mind, seat of intelligence: read, speak, calculations, remember past has white and gray matter like the spinal cord, but brain has additional outer layer surrounding the whole brain/cortex. -gray matter in white matter area

unfused tetanus

Further increase in stimulus frequency, lets say when a skeletal muscle fiber is stimulated at a frequency of 20 times per sec. then it can only partially relax bt successive stimuli. This results in muscle to progress to sustained, quivering contraction if another stimulus is applied before the muscle relaxes completely, then more tension results. This is temporal (or wave) summation and results in unfused (or incomplete) tetanus.

excitatory post synaptic potential

GP NOT AP -local depolarization of the postsynaptic membrane that brings the neuron closer to AP threshold. -Neurotransmitter binding opens chemically gated ion channels, allowing the simultaneous pas-sage of Na+ and K+

Surface markings of cerebral hemispheres

Gyri: Ridges. cortical reigon folds itself to form gyri sulci: shallow groves bt. flods fissures: deeper groves that sulci, separate diff. parts of brain

hyoid bone

Hyoid bone, an axial bone: unique in that it does not articulate w any other bones. It is suspended entirely by ligaments. It is located in the throat and above the larynx. It is horse-shoe shaped, muscles of the tongue & neck anchor to it. Hyoid bone: irregular bone.

myopic eye (near sighted)

If the eyeball is too long, the focal point will be in front of the retina, and you need to move the image back to the retina. You can do this by moving the object closer to the eye, or by putting a concave lens in front of the eye to spread out the rays of light.

adaption of receptors

In other words, receptors stop responding due to change in sensitivity in presence of constant stimulus. To keep the receptor from undergoing adaptation, the stimulus must vary a little. Certain receptors such as nociceptors & proprioceptors are slower to adapt compared to touch, smell, and thermoreceptors. i.e, you adapt faster to a hot bathtub.

motor end plate

In the process of signal transmission, motor neuron transmits the nerve impulse (AP) to a region of its target muscle cell membranes known as motor end plate, Ach is released from the motor neuron axon which binds to its receptors on the muscle and cause muscle contraction.

conus medullaris

Inferior to the lumbar enlargement. The spinal cord terminates in a cone-shaped structure @ L1 & l2 aka end of spinal cord

spinal nerves

Info gets in thru the dorsal roots & exits thru the venral roots. They fuse laterally to form the spinal nerves the spinal cord appears to be segmented because the 31 pairs of spinal nerves ( 8 pairs of cervical nerves (C1-C8), 12 pairs of thoracic nerves (T1-T12), 5 prs of lumbar (L1-L5), 5 prs of sacral (S1-S5), 1 pair of coccygeal (Co1) emerge at regular intervals from intervertebral foramina.

Cerebellum

Involved w coordinated and smooth moves like walking. The cerebellum functions below the level of conscious thought. For example, you decide to pick up a pen. The impulse for the arm movement comes from the cerebrum. The cerebellum then modifies these impulses so your arm and finger movements are coordinated and you don't reach past the pen. If injured you get clumsy w jerky motion. Cerebellum receives input from the motor cortex as well as the vestibular apparatus of the inner ear for balance.

temporal lobe

Key areas -primary auditory cortex -broca's area: speech/language production -wernicke's area: understanding spoken/language and written words damage to wernickes -fluent aphasia: spoken words are not meaningful -agraphia: can't write words in meaningful way -alexia: inability to read w/ comprehension

multicellular exocrine glands that are glandular epithelial

Merocrine: most secrete products by exocytosis as secretions are produced (sweat, pancreas)• Holocrine: accumulate products within, then rupture (sebaceous oil glands) Apocrine: accumulate products within, but only apex ruptures; whether this type exists in humans is controversial (maybe mammary cells?)

muscle sense

Muscle sense (proprioception) is the brain's ability to know where our muscles are and what they are doing, without our having to look at them & be aware of them. •Recall this is the job of stretch receptors (or proprioceptors or muscle spindles) that are located within muscles.

synapses

Nerve-nerve or nerve-muscle (effector cell) junctions. Nerve-nerve synapses are typically bt the axon of one neuron (presynaptic nerve cell) and dendrite of another neuron (postsynaptic neuron). In rare cases, synapses can be bt axon&axon; dendrites & dendrites; dendrites & cell body of another neuron. The gap bt the pre & post synaptics is the synaptic cleft.

inhibitory postsynaptic potential (IPSP)

Neurotransmitter binding to receptor opens chemically gated channels that allow entrance/exit of ions that cause hyperpolarization Makes postsynaptic membrane more permeable to K+ or Cl-•If K+ channels open, it moves out of cell•If Cl- channels open, it moves into cell -reduces likelihood of AP, causes hyperpolorization

Spongy bone

Not the weight-bearing part of the bone Contains trabeculae (sponge like structure) covered with endosteum -space bt trabeculae is filled w/ red marrow then to yellow marrow as you age Contains concentric lamellae with lacunae housing osteocytes but NO OSTEONS & NO CENTRAL OR PERFORATING CANALS

cerebrospinal fluid

On the floor or wall of EACH OF THE 4 ventricle is a spongy mass of blood capillaries called a choroid plexus. Ependyma, a type of neuroglia lines the ventricles & canals & covers the choroid plexi. Choroid plexus is where CSF is produced. CSF bathes the ventricles, canals of the CNS & its external surface. A small amount of the CSF fills the central canal of the spinal cord, but ultimately, all of it escapes thru 3 pores in the walls of the 4th ventricle -a median aperture & two lateral apertures. These leads into the subarachnoid space on the brain & spinal cord surface. From this space, CSF is reabsorbed by arachnoid villi, cauliflower-shaped extensions of the arachnoid meninx that protrude thru the dura mater into the superior sagittal sinus. It mixes w the blood in the sinus. functions: 1. buoyancy 2. protection 3. chemical stability: CSF rinses metabolic waste from nervous tissue hydrocephalus: large head due to accumulation of CSF

polysynaptic reflex

One or more interneurons connect afferent (sensory input) & efferent (motor neurons). Polysynaptic reflexes cause a withdrawalof a limb (flexor reflex) & crossed extensor reflexes in which the ipsilateral side is withdrawn, & the contralateral side is extended. Example of a polysynaptic reflex called flexor-cross extensor reflex: You step on a nail, pain receptors send afferent signals up the afferent nerves, through the dorsal root & into the spinal cord. Interneurons connect to the motor neurons (efferent nerves) and motor neurons connect to the muscles of your leg (flexor muscles) & you withdraw the leg that is painful. At the same time, the information goes to the contralateral leg muscles causing that leg to extend so you do not fall. interneuron facilitates sensory motor communication

pain

Pain is the subjective feeling when a nociceptor is stimulated. That is why managing a patient's pain is rather difficult because pain is an intensely personal experience. classification based and time (acute vs chronic) and location of receptors (somatic vs visceral aka internal pain)

spinal cord

Spinal cord & spinal nerves contribute to homeostasis by providing quick, reflexive responses to many stimuli. The spinal cord is the pathway for sensory input to the brain & motor output from the brain. Adult spinal cord is shorter than the bony vertebral column. ends (L1 or L2).

neruomuscular junction

Synapse (point of contact) where a motor neuron axon stimulates a muscle fiber (muscle cell). at least 1 motor nerve in muscle: the axons of the nuorns w/in the motor nerve divide into 100s of axon terminals. Ea motor neuron's axon terminal connects w the end plate (sarcolemma of a single muscle fiber) to form motor end plate or neuromuscular junction.

graded muscle responses

That is the amount that a whole muscle contracts depends on either 1. how often (frequency) the stimulus hits the motor unit (temporal stimulation) 2. how many motor units (strength) are stimulated (recruitment).

anterior chamber of eye

The area in front of the iris

Endosteum

The membrane covering the bony struts of spongy bone & all inner surfaces of bones (in bone)

Parietal vs. Visceral

The parietal layers of the membranes line the walls of the body cavity (pariet- refers to a cavity wall). (outside) The visceral layer of the membrane covers the organs (the viscera). (inside) Between the parietal and visceral layers is a very thin, fluid-filled serous space, or cavity.

temporal summation

When a second stimulus occurs after the refractory period of the first stimulus is over, but before the skeletal muscle fiber has completely relaxed the second contraction is actually stronger than the first. temporal summation produces smooth, continuous contractions that add up (summation).

myopic eye

When the light hits the lens in the eye, parts of it slows down because from one medium (air) it enters another medium (your tissues). The rest keeps going, and the light is bent. At some point, the bent light rays, posterior to the lens, converge at a focal point. Ideally, the focal point will fall on the retina. Image formed at focal point is upside-down & reversed from left to right. light rays enter the eye and hit the lens, the light is bent. The bent light rays converge at a focal point. Ideally, the focal point will fall on the retina.

filum terminale

a fibrous strand extension of the conus covered with pia mater that extends inferiorly & fuses w the arachnoid mater & dura mater & anchors the spinal cord to the coccyx.

lateral masses of ethmoid bone

a large mass on each side of the perpendicular plate. The labyrinth named as such because it has air spaces (ethmoid sinus) called the ethmoid cells. compose most of the wall bt the nasal cavity & the orbits. contains 2 thin projections lateral to the nasal septum -superior nasal concha & the middle nasal concha (turbinate).

spinal tap

a local anesthetic is given, a long hollow needle is inserted into subarachnoid space to withdraw CSF. The spinal cord ends around L2, however, the spinal meninges (dura mater & arachnoid) & circulating CSF extend to the S2. Between L2 & S2 the spinal MENINGES are present, but the spinal cord is absent. Thus, the needle only pushes the spinal nerves out of the way. The highest point of the iliac crest passes thru L4 & is used as a landmark to administer the spinal tap.

fused tetanus

a single smooth sustained contraction in which individual twitches cannot be detected. In the real world, fused tetanus happens infrequently. Prolonged muscle contractions lead to muscle fatigue, & the tension within the muscle drops to zero. no relation bt. stimuli if stimulus frequency increases further (more than unfused)

conjunctiva

a thin membrane lining the eyelids, which is also folded over the white (sclera) of the eye & merges with the corneal epithelium. -mucous membrane lines inside of the eyelids & covers the front of the eyeball. -The portion that lines the eyelids is the PALPEBRAL conjunctiva, while the part covering the white part of the eye ball is the BULBAR (ocular) conjunctiva. -The bulbar conjunctiva covers only the white part of the eye, not the cornea. The inflammation of bulbar conjunctiva causes the painful redness called conjunctivitis (AKA pinkeye). Pinkeye can be caused by bacteria or viruses or less contagious allergy. -conjunctival sac: space bt. bulbar and palpebral conjunctiva -When the eye is closed, a contact lens would rest in this space & it is in this space that eye drops are applied. Conjunctivitis: is the inflammation of this membrane.

pain pathway

afferent pain fibers synapse w interneurons in the dorsal horn of the spinal cord, cross over eventually and run up the lateral spinothalamic tract of the spinal cord into the thalamus and eventually ends at the somatosensory cortex located in the post central gyrus to be interpreted

relative refractory period

after the absolute ref. period when most Na+ channels have returned to their resting state. The threshold for another AP is much HIGHER than the normal but a strong stimulus can fire another AP.

chemical synapses

allow the flow of neurotransmitters bt neurons. process 1. Axonal terminal of the presynaptic neurons has vesicles filled w neurotransmitters. 2. Neurotransmitter is released by an AP into the synaptic cleft, picked up by the receptors on the postsynaptic neurons' dendrites. 3. In chemical synapses, the transmission of an impulse is one-directional, from presyn to postsynaptic nerves. 4. The neurotransmitter binding to the post synaptic nerve causes channels to open. 5. Opening these ion channels permits the flow of the current locally. 6. Now that the neurotransmitters present in the cleft have done their job, they are either destroyed by degrading enzymes or picked up by the presynaptic vesicles (for recycling). at the same time 1.AP arrives at axon terminal of presynaptic neuron 2.Voltage-gated Ca2+ channels open, and Ca2+ enters axon terminal-Ca2+ flows down electrochemical gradient from ECF to inside of axon terminal 3.Ca2+ entry causes synaptic vesicles to release neurotransmitter 4.Neurotransmitter diffuses across the synaptic cleft and binds to specific receptors on the postsynaptic membrane 5.Binding of neurotransmitter opens ion channels, creating graded potentials 6.Neurotransmitter effects are terminated-By reuptake, degradation by enzymes, diffusionaway from the synaptic cleft.

outer hair cells

amplify the low level sounds entering cochlea.

ethmoid bone

an anterior cranial bone bt the orbits of the eyes. It separates nasal cavities from the brain. It is a very porous and delicate bone, 3 major portions: cribriform plate, perpendicular plate, and lateral mass

3 divisions of skull

anterior, middle, and posterior crainal l fossa

fovea

approximately 50% of the nerve fibers in the optic nerve carry information from the fovea, while the other 50% carry information from the rest of the retina. high level of cones

posterior chamber

area bt the iris & the lens

T tubules

arising from the cell membrane that dip into the cell's interior & go bt folds of the sarcoplasmic reticulum. They are filled w the extracellular fluid. ***The T-tubules have the same properties as sarcolemma, so AP conducted by sarcolemma travels along the T tubules into the cell interior.

ciliary gland (moll gland)

associated more directly w the eyelash follicles. They are modified sweat glands (at the base of eyelashes). Their infection produces a cyst called a sty. typically smaller in size, more painful, and infection by S. aureus of the oil glands.

third ventricle

attached to the lateral ventricles by the interventricular foramen. 3rd ventricle is inferior to the corpus callosum. From here, a canal called cerebral aqueduct passes down the core of the midbrain to the 4th ventricle.

myasthenia gravis

autoimmune disease in which the body makes antibodies to the acetyl choline receptors on surface of muscle cells. Therefore, the Ach cannot easily bind to its receptor and the muscle contractions are weak. Symptoms of the disease are droopy eyelids, difficulty speaking & swallowing, and general muscle weakness.

presynaptic neuron

axon

factors that influence AP

axon diameter: larger the axon diameter (NOT LENGTH), the faster the impulse due to less resistance myelination: more myelinated axons the faster the nerve impulse. The AP jumps over from one node of Ranvier (1-2 um) to another node of Ranvier known as saltatory conduction. continuous conduction: movement of impulse down unmyelinated axon (slower than saltatory conduction)

lower motor neuron

basically a nerve cell that goes from the spinal cord to a muscle. It exits the spinal cord by way of the ventral root of the spinal nerve & goes out to skeletal muscle.

spinal shock

begin 1h after injury & lasts about 48h. However, typically if the function doesn't return after 24h-48h then the paralysis is likely permanent.

mastoid process

behind ears, filled w/ air sinuses

refraction of light

bending of the light as it travels from one medium (i.e, air) to a different medium (i.e, H2O). That is why when you use oil immersion lens in your microscope you put a drop of oil on the slide to prevent light bending.

brain waves in sleep

beta: awake, normal alert, rhythmic, somewhat irregular. 15-30 HZ Alpha: relaxed, calm, meditation, creative visualization. 9-14 HZ theta: deep relaxation, always abnormal in awake adults but can be normal in children. 4-7 HZ. delta: during deep deep sleep, high amplitude, Slow waves. Normal in infants but abnormal in awake adults1-3 HZ. Mnemonic: "Brain Activity That Decreases".

epidural space

between vertebrae & spinal dura mater filled w fat & blood vessels.

cauda equina

beyond the level where the cord ends, the spinal nerves from the lumbar, sacral, and coccygeal regions hang in the vertebral foramen like a horse's tail

compact bone

bone composed of osteons w/o marrow filled cavities

ossification

bone development

sesmoid bones

bone that forms w/ in tendon (ex. patella, base of big toe)

spongy/ cancellous bone

bones composed of trabeculae & marrow filled cavities

appendicular skeleton

bones of upper & lower limbs plus the pectoral girdle (clavicle & scapula) and pelvic (hip bones) girdle.

central nervous system

brain and spinal cord. this is the integration and command center

brain ventricles

brain has 4 internal chambers (ventricles) that are fluid (CSF) filled, are continuous w ea other & connect to the central canal of the spinal cord. The 4 ventricles are carpeted w ependymal cells. Ependymal cells synthesize the CSF. CSF acts as a shock absorber.

roots

bundles of axons

cancer types

carcinoma: cancer of epithelial cells sarcoma: cancer of CT leukemia: cancer of blood forming tissue

striated tissue

cardiac and skeletal muscle -striation in muscle due to presence of A & I bands

somatic motor nuerons

carry the order (impulses) to skeletal muscles. 1. upper motor neuron (think of brain) -Pyramidal cells in primary motor cortex 2. lower motor neuron (think of spinal cord) -Ventral horn motor neurons -Innervate skeletal muscles

spinal cord enlargements

cervical and lumbar -where large # of axons supplying arms and legs enter and exit

taste buds

chemoreceptors for taste, located on the tongue, that respond to chemical substances dissolved in saliva. Most of these chemical receptors are located on tongue in PAPILLAE, peg like projections on the tongue.

Epilepsy

chronic brain disorder characterized by recurrent seizure activity there are short, recurrent, periodic attack of motor, sensory, or psychological malfunction. Groups of brain neurons abnormally discharge, sending impulses over their conduction pathways & causing seizures (uncontrolled electrical activity in the brain).

sensory receptors

classified by stimulus: -Mechanoreceptors: i.e, receptors for sensing light vs deep touches in the skin. Also receptors for vibration, stretch, etc. -Thermoreceptors: i.e, hot & cold receptors. Interpretaion of Temp. -Nociceptors: respond to potentially damaging stimuli, that result in pain, i.e, extreme cold, inflammatory chemicals. -Chemoreceptors: respond to chemicals (examples: smell, taste, changes in blood chemistry). classified by location -Exteroceptors: found in the skin, respond to stimuli from outside the body. i.e, receptors in skin for touch, pain, and temperature. -Interoceptors (visceroceptors): This category respond to stimuli w/in the body. I.e, change in PH, thirst, pain within the body. -Proprioceptors: Respond to stretch in skeletal muscles, tendons, joints, ligaments, and connective tissue coverings of bones and muscles. they constantly let our brain knows of our body movement, how our body is located in space. classified by receptor structure -simple receptor for general sense •Modified dendritic endings of sensory neurons •Are found throughout body and monitor most types of general sensory information types: 1. free dendritic endings: found everywhere, mainly in the skin & connective tissues. Respond to pain, temp, itch, and some respond to pressure. 2. encapsulated dendritic endings. Terminal of a sensory nerve are surrounded by a connective tissue wrapping. Most are mechanoreceptors or proprioceptors. -receptor for special sense vision, hearing, equilibrium, smell, taste

limbic system

closely involved w memory, particularly the hippocampus(short-term memory), the amygdala, and the nucleus basalis. If these structures get damaged, you may get amnesia retrograde amnesia: memory loss before trauma anterograde amnesia: memory loss after trauma

nerve roots

come in dorsally & exit ventrally,

spinal nerves

come off the cord & run away from the cord through the intervertebral foramina & out to the body. Cervical spinal nerves comes out above their respective vertebrae. All other spinal nerves come out below their respective vertebrae. Thus there are 8 cervical nerves even though there are only 7 cervical vertebrae.

ligaments

composed of regular CT but connect bone to bone

treppe

condition where after a muscle has been stimulated & contracted several times contracts more forcefully to the same stimulus than it initially did. principle behind an athlete's warm-up. Treppe occurs in a muscle fiber that has rested for a prolong period. Explanation: may be an increase in Ca++ levels around the myofibrils. That is the Ca in response to the 1st stimulus are not taken up completely by the SR before a 2nd stimulus cause the release & availability of more Ca for contraction. Also the warmth generated makes muscle enzymes work better. Thus treppe is when a rested muscle is stimulated repeatedly w same stimuli at a frequency which allows COMPLETE relaxation between stimuli the second contraction produces a slightly greater tension (amplitude, stronger contraction)than the first, & the 3rd contraction produces greater tension than the 2nd. After a few contractions, the levels of tension produced by all the contractions are equal. Treppe induces peak performance of the muscles.

strabismus

condition where the 2 eyes don't track together, & one either •looks too far towards the nose (cross eyes) or too far laterally. This can be corrected w special glasses or w surgery on the deficient extraocular muscle

astigmatism

condition where the surface of the cornea or lens is uneven and tends to scatter light as it enters the eye, causing blurred vision.

rootles

connect ea spinal nerve to a segment of the cord by even smaller bundles of axons

corpus callosum

connects L & R hemispheres

tendon

consist of dense regular CT & attach muscles to bones

Eyelids (palpebrae)

contains skeletal muscle that enables the eyelids to close & cover the front of the eyeball.

sacral plexus

contains the PUDENTAL NERVE (innervates a lot of pelvis) and sciatic nerve (supplies leg)

medulla oblongata

contains the cardiovascular centers (adjust HR), vasomotor centers (regulate diameter of blood vessels & thereby blood pressure, respiratory centers (regulate breathing), center for vomiting, hiccupping, swallowing, coughing. (resp. for vital sign)

dorsal root ganglion

contains the cell bodies of the incoming sensory nerves (pseudo-unipolar neurons).

parasympathetic control of oculomotor nerves

contracting the ciliary muscles (forming a circumference surrounding the lens) under the control of parasymp of the oculomotor nerves, we loosen the suspensory ligaments & make the lens fatter, enabling us to focus on near vision.

convergence

convergence when more presynaptic neurons than postsynaptic neurons presynap neurons are said to converge on the postsynap neurons.

Sutures of the skull

coronal, sagittal, lambdoid, squamous

trochlear nerve

cranial motor nerve function: innervates the superior oblique muscle in eye imbalance: double vision

tendon

ct that links muscle to bone, rope like

epithelial membrane types

cutaneous, mucous, serous

sarcoplasm

cytoplasm of myocyte

pia mater

delicate tissue, clings tightly to the brain. Pia mater follows every convolution of the brain. Is enriched w a lot of tiny blood vessels that feed brain. ** It makes the choroid plexus that secretes CSF.

post-synaptic neuron

dendrites

Dura mater

dense irregular connective tissue -One layered attached to the skull (the periosteal layer). -The second is called the meningeal layer forms the true covering of the brain. The 2 membranes are fused except in a few areas where they enclose the dural sinusesthat collect venous blood from the brain and send it back to the internal jugular veins of the neck and back to the heart the dura mater is distinctly separated from the vertebrae, forming an epidural space. The meningeal dura sends "sheet" into the brain to help secure it to the skull (keep brain in place w/ in skull) at 3 places: •1. Falx cerebri: the midsagittal fold, goes into the longitudinal fissure bt the hemispheres. It is anchored anteriorly to the crista galli of the ethmoid bone. 2. Falx cerebelli: goes up bt the cerebellar hemispheres; along vermis of cerebellum. •3. tentorium cerebelli: bt the occipital lobes & the cerebellum.

motion sickness

disagreement bt the visually seen movement & the vestibular's sense of movement. If your eyes are focused on the interior of an airplane & they tell you are immobile, but your semicircular canals & utricle/saccule are telling you that you are moving all over the place,

Physiology of Tasting

dissolved chemical enters the crevice next to the papilla & stimulates a hair cell receptor in the taste bud. This generates an action potential in the sensory nerve fiber, the AP travels up the facial nerve (cranial nerve IV) if from the anterior 2/3 of the tongue or the glossopharyngeal nerve (cranial nerve IX) if from the posterior 1/3 of the tongue. Vagus nerve (CN X) transmits from epiglottis & lower pharynx. In the brain, we interpret the input & say "yum" or "yuk".

all spinal nerves have

dorsal root: afferent fibers enter spinal cord ventral root: efferent fibers leave spinal cord spinal nerves split into 3 branches/ rami

Meningies

dura mater, arachnoid mater, pia mater protective membranes that cover the brain and spinal cord -CT not epithelial

descending pathway

efferent impulse from brain to spinal cord types: direct pathway: pyramidal tract indirect: all others

resting membrane potential

electric charge difference across the plasma membrane of an unstimulated (resting) cell ' about -70mv (membrane is POLARIZED) generated by: 1) Differences in ionic composition of ICF (intracellular fluid) and ECF (extracellular fluid) Immediately inside the cell (ICF): K+ is high, Na+ is low. Immediately outside the cell (ECF): low in K+ and high in Na+. 2) Differences in plasma membrane permeability.

tendon sheath

elongated bursa that wraps completely around a tendon subject to friction, like a bun around a hot dog. Ex. In the wrist, ankle.

six extrinsic muscles of eye

enable eye to follow moving objects, maintain shape of eyeball, and hold it in orbit cranial nerves that innervate these muscles are - oculomotor (III), trochlear (IV), abducens (VI) cranial nerves. Eyeballs also converge which keeps even close objects focused on the retina. If you do a lot of really close work, you can get "eye strain" as your muscles around the lens & your medial rectus become fatigued.

types of tissue

epithelial connective muscle nervous stem cells

aqueous humor

filled in anterior segment of eye continually being produced by the capillaries in the ciliary process in the posterior chamber, circulates to the anterior chamber thru the pupil, and is drained through the canal of schlemm (the scleral venous sinus) which are small veins at the junction of the iris & cornea goes back to the circulatory system. Aqueous humor has nourishing function to lens & cornea since they are avascular. If the canal of schlemm is blocked, aqueous humor cannot leave the eye, pressure inside the eyeball increases, putting pressure on the retina & optic nerve to the point of damage & potential blindness. This is glaucoma.

subarachnoid space

filled w CSF

subdural space

filled w serous fluid not CSF

lacrimal caruncle

fleshy bulb in the medial canthus, secretes oily substance to lubricant & protect the eye. This is the "sleep" you find in your eye when you wake up in the morning.

synovial joint

freely movable joint -synovial fluid separates hyaline cartilage @ apposed bone ends has.. 1. joint capsule (extending from the periosteum of each articulating bones). 2. synovial membrane: secretes synovial fluid. 3. joint cavity: contains synovial fluid. 4. articular cartilage: hyaline cartilage on bones 5. ligaments: strengthening the joint. articular capsule = fibrous capsule + synovial membrane (inner most)

spinal meningies

from inside to outside pia mater arachnoid mater dura mater bt pia and arachnoid mater is subarachnoid space bt. arachnoid mater and dura mater is subdura space

CT sheaths of skeletal muscle

from outside to inside epimysium: covers whole muscle, connected to deep fascia perimysium: covers fascicles endomysium: covers myocyte -contains capillaries to supply muscle cell -myosatellite cells stem cells that repair damaged muscle tissue nerve fibers that control muscle

cranial bones

frontal bone (1): forms forehead -supraorbital margin is ridge near eyebrows -gabella is space bt eyebrown parietal (2): at side walls of skull, surrounds all sutures occipital bone (1): back of head -occipital condyle is where skills rest on vertebrae temporal bone (2): below parietal bones -have 2 ear canals

paranasal sinus

function 1) make the skull lighter in weight, because air is lighter than bone. 2) Provide resonance for the voice, meaning more air to vibrate & thus deepens the pitch of the voice. 1. Frontal sinus: in the frontal bone, above the eyes 2. Ethmoid sinuses: behind the corners of the eyes. 3. Sphenoid sinus: medial & inferior to the eyes. 4. Maxillary sinus: on either side of the nose in the face.

parietal lobe

function: receiving & interpreting most sensory signals except for smell, hearing, and vision key areas: primary somatosensory cortex/ post central gyrus: receives general sensory inputs from skin receptors and feel and interpret cutaneous sensations (pain, touch) -contralateral primary gustatory cortex: registers taste

electroencephalogram *EEG)

graphical record of the activity of the brain. The electrical potential differences bt various areas of the brain are measured & recorder as "brain waves"

tract

group of axons together w/in CNA

nuclei

group of cell bodies all together in CNS

ganglion

group of cells bodies in PNS

epiphyseal plate

growth plate -separated diaphysis from epiphysis -made of hyaline cartilage in youth, plate expands for you to get taller -epiphyseal line = adult and no more height growth

dreams

happen mostly during REM. 3 common themes reported for dreams: falling, being chased or attacked, repeatedly to do something but failing. Majority of dreams (60%) are associated w sadness, fear, anger where as 18% were happy. 21% of dreams reported in color. It appears that the concerns of daily life, i.e, financial issues, rejection, influence the contents of a dream. Other influencing factors are outside stimuli. There is another interesting source, that is half-in & half-out (lucid dream, mainly occurs during REM). That is you know you are having dream.

red muscle fibers

has more myoglobin, a red pigmented protein that binds to O2 similar to hemoglobin except that myoglobin is stored in the muscles. Because myoglobin is near muscle, its O2 can be immediately used by muscle fibers to generate energy (ATP) red muscle activity: ex.maintaining posture. ex.geese have to fly long distances when they migrate, so their breast muscles are dark meat & their leg muscles are white.

Dark red meat

has more myoglobin. These muscles are slow twitch & fatigue resistant.

hippocampus

has to do with the formation of memories. It is part of the temporal lobe on the floor of the lateral ventricle.

white meat

have little myoglobin, are fast twitch and fatigue easily. White muscle activity: ex. hitting a baseball. ex. Turkeys who rarely fly, but spend most of their time on their legs have dark meat in their legs and white meat in their breasts.

eyelashes

helps keep dust out of eye

synergist

helps prime movers

hyperopic eye

if the eyeball is too short, the image falls behind the retina, and you need to move the image up to the retina. You can do this by moving the object farther away from your eyes, or by using a convex lens to drag the image up to the retina.

origin of a muscle

immobile attachment of muscle the structure that the origin is attached to is not moved by the contraction of the muscle.

chondrocyte / chondroblast

in cartilage chondroblast secrets ground substance chonrocyte is confound in lacunea

dermatome

in dorsal rami innervation of skin via dermatomes area of skin innervated by cutaneous branches of single spinal nerve -All spinal nerves except C1 participate in dermatomes -Extent of spinal cord injuries ascertained by affected dermatomes -Most dermatomes overlap, so destruction of a single spinal nerve will not cause complete numbness

rhodopsin

in rods -Rhodopsin forms in dark & requires vitamin A for its formation. -Light chemically changes rhodopsin & breaks it down. The chemical changes made in rhodopsin generate an electrical signal that is transmitted through the optic nerves to where some fibers cross over to the other side at the optic chiasma, then the 2 optic tracts go on to the visual cortex of the cerebral cortex.************** bright light, rhodopsin breaks down (photo-bleached) to OPSIN (protein component)& RETINAL (a form of vitamin A) and in the breaking down process it converts physical (light) signals to electric signals (nerve impulse). When we go from bright light into darkness, we are temporarily blinded because it takes a few seconds for us to make rhodopsin, from opsin plus retinal, for vision and adjust to the dim light.

merkel cells

in stratum basale of epidermis -associated w/ light touch and discrimination of shape and textures

Myocyte

individual muscle cell -1 cytoplasm surrounds many nuclei

memory

info acquired thru learning is stored in our brain and retrieved (the ability to recall). Neuron plasticity plays a major role in memory. The parts of the brain associated w memory include the associated cortex of the frontal, parietal, occipital & temporal lobes, as well as parts of the limbic system (especially the hippocampus & amygdaloid nucleus) & diencephalon.

reflexes

instantaneous movement, involuntary, predictable response to a stimulus. It is mediated via the reflex arc. It happens at the spinal cord level W/O the BRAIN involvement Reflexes occur over specific pathways referred to as reflex arcs. Ex: you touch a hot plate you immediately withdraw your hand. components •1. receptor: there is a receptor where the initial stimulation occurs. 2. sensory neuron: it transmits the afferent stimulus to the CNS & enters the spinal cord via the dorsal root (its cell body is w/in the dorsal root ganglion) 3. integration center: it is w/in the CNS and processes the incoming information 4. motor neuron: carries an efferent impulse out to an effector organ. 5. effector: muscle or a gland responding to a motor neuron.

cingulate gyrus

involved in expressing emotions via gestures & resolves mental conflict.

isometric contraction

involves contraction without movement. the length of the muscle remains the same as the muscle tension increases. Ex. of isometric exercise, put your palms together & push one hand against the other, you feel your arm muscles contracting. If both hands push equally, there is no movement. Isometric exercise helps to improve muscle strength & tone but is not aerobic exercise.

midbrain

involves visual and auditory reflexes

spinal bifida

is a congenital defect in which the vertebral column fails to fuse properly. due to lack of folic acid (vitamin B)

cochlea

is like a coiled snail. If it were uncoiled, it would look like a long tube with a wedge-shaped membrane running down the length of it. consists of 2 separate chambers: the inferior scala tympani & the superior scala vestibuli. actual organ for hearing, the organ of corti, separate these chambers. The organ of corti consists of an upper membrane (the tectorial membrane), a lower membrane (the Basilar membrane), and a series of hair cells (called hair cells because of the tufts of stereocilia on the apical surface of the cells into the scala media) attached to the basilar membrane.

brain stem

is responsible for the rigidly programmed, automatic behaviors that keeps us alive. 1. midbrain 2. pons 3. medulla oblongata

pain threshold

it is the point at which the pain begins to be felt.

rami communications

joined to the base of the ventral rami of the thoracic spinal nerves and contain autonomic nerve fibers

articulate

joint

frontal lobe

key areas: •Prefrontal cortex: it is the site of our "conscious intellect", where learning, memory, personality occur. •Primary motor cortex: located in precentral gyrus, & provides CONTROL over our skeletal MUSCLE. Damage here can cause paralysis. •Premotor cortex: anterior to the primary motor cortex controls PATTEREND, learned motor skills .•Broca's area: above the tip of the temporal lobe, is the MOTRO SPEECH area. •Nucleus basalis: involved with MEMORY Nucleus basalis: involved w MEMORY (motor). Is a group of neurons in the basal forebrain which has wide projections to the cerebral cortex & is rich in Ach & Ach-esterase. The damage to nucleus basalis occurs in Alzheimer's & Parkinson's.

midbrain

large motor tracts running from the cortex to the cerebellum & spinal cord

pain tolerance

level of pain a person is willing to accept

interneurons

lie bt motor and sensory neurons (they are typically w/in the CNS). They make up 99% of the neurons of the body.

H zone

light band w. myosin seen in resting of muscle

functional brain systems

limbic system and reticular formation

fourth ventricle

located inferior to the 3rd, it is a small triangular chamber bt the pons & cerebellum. The fourth ventricle is continuous w the CENTRAL CANCAL of the spinal cord. 3 openings in its walls connect it to the subarachnoid space

tarsal glands (meibomian glands)

located w/in the tarsal plates at the edge of the eyelids just behind the eyelashes. They secret an oily substance that mixes w the tears & lubricate the eye & keeps the eyelids from sticking together. Chalazion is a cyst due to inflammation of the tarsal glands (Meibomian). Chalazion is more of inflammation nature and less of infection and is less painful and larger in size.

red marrow

location for hematopoiesis (blood cell formation) -in babies Red marrow is found in all spongy bone -eventually becomes yellow marrow except a few bones (head of the femur and humerus, ribs, vertebrae, sternum, and the hip)

How muscles are named

location, shape, size, direction of fibers, number of origins, location of attachments, action

paresthesia

loss of sensation only, motor is intact ex. diabetes (no pain in feet)

paralysis

loss of the motor function, the inability to voluntarily move muscles. types flaccid: if lower motor neurons in the ventral root horn cells are damaged impulses cannot reach the skeletal muscles. In other words, impossible to move that limb. i.e, accident injury, polio. spastic: if the injury is in the primary cortex of the brain (upper motor neurons) then the person cannot move the muscles but the reflex activity remains intact & the muscles continue to be stimulated. i.e, CP, MS, stroke.

pia matter

lots of blood vessels

cervical plexus

made up of the ventral branches of the first 4 cervical nerves (C1-C4). Most branches of this form cutaneous nerves, i.e, innervate skin of the neck, ear, etc. It gives rise to the PHRENIC NERVE that supplies the diaphragm (phrenic nerve irritations causes hiccups) damage leads to inability to move diaphragm (need ventilator)

adrenal medulla

major organ of sympathetic NS -secretes a lot of epinephrine & some norepinephrine -stimulated by preganglionic symp fibers

axial skeleton

making up the central support axis of the body skull bones, vertebral column, and rib cage but not the clavicles & scapula.

Z line (disc)

marks boundary of adjacent sarcomere

osteoctye

mature bone cells

pacinian corpuscle

mechanoreceptors in the reticular layer of the dermis. They are nerve endings in the skin responsible for sensitivity to vibration and pressure. used to detect surface texture, i.e, rough vs smooth.

reticular formation

mediating the overall level of consciousness (alertness), regulation of breathing, and transmission of sensory stimuli to higher brain regions. diffuse network of nerve pathways in the brainstem connecting the spinal cord, cerebrum, and cerebellum, and medulla, pons, and midbrain, governs arousal of the brain as a whole. helps to maintain the brain in an alert state, but also helps to filter out repetitive or weak stimuli such as feeling the watch on your wrist. 99% of all stimuli is not relayed to consciousness). LSD removes these filters, that's why LSD users get sensory overload. Reticular formation extends from the superior part of the spinal cord, throughout the brain stem, and into the inferior part of the diencephalon. Severe injury to RAS leads to coma. has ascending (sensory) and descending (motor) functions reticular activating system (RAS) which consists of sensory axons that project to the cerebral cortex both directly & through the thalamus. -RAS is active during awakening from sleep and also maintains consciousness. Both visual and auditory and other sensory stimuli except for olfactory stimulus activate RAS. That's why people who die in house fires succumb to smoke inhalation w/o awakening. Damage to RAS results in coma.

vascular tunic

middle layer of eyeball key features choroid layer: vascular brown layer, providing nutrition to eye -dark color keeps light from reflecting and scattering after entering eye ciliary body: suspensory ligaments attach to ciliary body that control the the shape of the lens iris: color part of eye -contains only brown pigment entering eye -merges w/ pupil and ciliary body - a lot of pigment gives brown eye pupil: -dark hole in center of eye -light enters eye here -smooth muscle in iris control the size of pupil -regulates amount of light entering eye**** -brown pigment ONLY

hypoglossal nerve

mixed (mostly motor nerve) function: supplies tongue, manipulation of tongue imbalance: difficulty w/ speech & swallow

vagus nerve

mixed nerve VARY IMPORTANT function: only cranial nerve that leaves the head & neck to supply things in the thorax & abdomen. Nearly all motor fibers are parasympathetic. For ex, vagus nerve firing slows down the heart rate.

facial nerve

mixed nerve function: supplies the muscles of facial expression & the sensory taste buds from the anterior part of the tongue. imbalance: Bell's palsy (paralysis of face_

glossopharyngeal nerve

mixed nerve function: supplies the tongue & pharynx helps w/ taste and swallowing imbalance: impairs swallowing & taste

spinal nerves

mixed nerve named according to their point of issue from the spinal cord, i.e, 8 pairs of cervical spinal nerves (C1-C8). They leave the spinal cord thru the intervertebral foramina between vertebrae. serve all parts of body except head & some areas of neck

accessory nerve

mixed nerve (mostly motor) function: supplies the walls of the pharynx & larynx & some muscles of the neck & shoulders. They are unique because they emerge from the spinal cord and NOT the brain. imbalance: shrugging difficult

trigeminal nerve

mixed nerve, largest cranial nerve function: principle sensory nerve going to the head & also supplies the muscles for chewing. imbalance: inflammation gives excruciating pain

sacroplasmic reticulum

modified ER inside the fiber cytoplasm. -Is a sheet of sER that surrounds ea myofibril & is involved w storage, release, reuptake of Ca++.

abducens nerve

motor function: supplies later rectus muscle of eyeball

oculomotor

motor function: moves 4/6 eyeball muscles (somatic), constricts the iris in parasymp sys. muscles: superior, inferior, lateral, medial rectus imbalance: lazy eye

eccentric contraction

muscle lengthens and generates force. EX: laying a book down causes biceps to lengthen while generating a force. occurs when a muscle is contracting, and an external force (a heavy book in the previous slide)is trying to lengthen the muscle. The classic mechanism for a muscle strain is an eccentric contraction. Hamstring strain and muscle spasm are examples of injury due to eccentric contractions. Conversely, physical therapists and strength trainers often use eccentric exercises when strengthening muscles.

concentric contraction

muscle shortens and does work. Ex: biceps contracts to pick up a book

agonists/ prime movers

muscles that are responsible for producing specific movement s

multiple sclerosis

myelin sheath destruction. disruptions in nerve impulse conduction unknown causes Symptoms: muscle weakness, dizziness & vertigo, numbness, fatigue, pain, depression, blurred vision, lack of coordination & balance. Relapsing/remission cycle (comes & goes; perhaps every 1-2 yrs). -ea episode causes MORE damage (degeneration) of the myelin, and therefore speeds up the progression of the disease

white matter

myelinated and nonmyelinated nerve fibers allow communication bt parts of spinal cord, and spinal cord and brain. Run in 3 directions: 1. Ascending: up to higher centers (sensory inputs) 2. Descending: from brain to cord or lower cord levels (motor outputs) 3. Transverse: from one side to other (commissural fibers)

white matter

myelinated axons, speeds up impulse transmission x100

Myofibrils

myocyte cytoplasm packed into a rod like structure -actual contractile unit of muscle

nail anatomy

nail body: visible portion of the nail Nail root: portion that is buried in a fold of skin Lunula: whitish crescent-shaped at the nail end. nail bed (hyponychium): is a thickened region of stratum corneum under the nail body. secures nail to finger tip. Pinkish in well-oxygenated and bluish color (cyanotic) in poorly-oxygenated individuals. cuticle (eponychium): narrow band of the stratum corneum nail matrix: divides to produce new nail cells.

zygomatic process and arch

near cheek

neuron

nerve cells made of... 1. soma (body):here the nucleus, most of the mitochondria & cytoplasm, Nissl bodies (ER) are located. 2. dendrite: short processes which receive the impulses and send it to the cell body. They are not myelinated. 3. axon one long process (4ft long sometimes), arising from the AXON HILLOCK & with a lot of branches (terminal branches) at its end. Axon terminals are filled with vesicles which have the neurotransmitters stored in.•Axons: generate & transmit the nerve impulses away from the cell body. characteristics: 1. longevity 2. amitotic 3. high metabolic rate (needs o2 and glucose)

peripheral nervous system

nerves & ganglia outside CNS -cranial and spinal nerves

nerve fiber

neuronal process (axon) that emerge from the cell body of a neuron.

absorption of light

no lights reflected. In other words, all light wavelengths absorbed by the object, we see the object as black. Chlorophyll absorbs all other wavelengths except green. So we see plants green.

Antagonist

opposing muscles

extrinsic muscle

origin & insertion are far apart, i.e, upper arm vs the lower arm.

Compact bone's structural unit

osteon/ haversian system: group of hollow haversian/ central canal: center of osteon & contains nerves & small blood vessels & nerve fiber lamellae: rings w/in an osteon lacunae: cavities between lamellae w/ osteocyes inside, connected via canaliculi extensions to another & haversian canal canaliculi: hair like canals connecting lacuna. Allow communication bt osteocytes of an osteon. nutrients and waste are replayed here volkmann's/ perforating canal: run at R angel to Haversian canal connecting central canals of adjacent osteons

stretch mark

over stretching of dermis, tearing elastic fibers

phantom pain

pain or discomfort felt in an amputated limb

nociceptor

pain receptor stimulated by temp, pressure release pain-producing chemicals such as bradykinin (one of the most powerful pain-producing agent), histamine, K+, ATP, prostaglandin, and acids.

referred pain

pain that is felt in a location other than where the pain originates The pathways (spinal segments) that visceral pains take to go to the brain are the same as those used by somatic pain; therefore, the brain may interpret visceral pain coming from a somatic area

paraplegia

paralysis from the waist down

quadriplegia

paralysis of all four limbs

hemiplegia

paralysis of one side of the body

plexus

part of ventral rami, SOMATIC Within plexus, fibers crisscross so that: 1.Each branch contains fibers from several different spinal nerves .2. Fibers from ventral ramus go to body periphery via several routes. -each limb muscle is innervated by more than one spinal nerve, so damage to one does not cause paralysis.

sacrolemma

plasma membrane of a muscle fiber/cell/myocyte

tears

produced in LACRIMAL GLANDS /in the orbit & at the upper outer corner of the eyeball. Blinking spreads the tears & washes the surface of the eyes. Tears is mostly H2O plus 1% NaCl & contains lysozyme, an enzyme that kills bacteria. Tears then drain through 2 openings called lacrimal PUNCTA into the lacrimal canals, which merge to form a single lacrimal sac(in the lacrimal bone). The lacrimal sac drains into the nasolacrimal duct which empties tears into the nasal cavity. That's why crying makes the nose run

REM

rapid eye movement -full night = 4-6x through whole cycle -1st REM cycle is 1 min, increase in REM and decrease in NREM as you go through more cycles -last REM is 30-60min (explains why you sleep through alarm) -alcohol & aging decreases REM

amygdala

recognizes angry or fearful facial expressions, assesses danger, and elicits fear response.

sympathetic activation of eye

relaxing the ciliary muscles under the control of symp nerves, , we enlarge the circumference of the ciliary muscles, and tension in the suspensory ligaments stretches the lens & make the lens flatten, thus allowing us to focus on far things

neurotransmitter (chemical messenger)

released into a space bt 2 nerves called synaptic cleft or simply synapse. Neurotransmitters either stimulate or inhibit the next neuron w which the axon is in close contact.

absolute refractory period

right after an AP is fired the cell (axon) has to rest before another AP is fired. Voltage-gated Na+ channels are open so neuron cannot respond to another stimulus.

tinnitus

ringing, swishing, or other type of noise that seems to originate in the ear or in the head in the absence of auditory stimulation. It could be due to ear infection, side effect of medications, natural hearing impairment as in aging, wax build up, inflammation of the vestibulocochlear nerve or middle ear, etc.

epiphysis

rounded ends of long bone -exterior is compact bone and interior is spongy bone -surface/ end of joint is covered w/ hyaline cartilage

supporting cells in PNS

satellite cells: surround cell bodies of neurons. Same funcs as astrocytes in CNS Schwann cells: -surround PNS cells & form myelin sheaths around the axons in thicker nerve fibers. -Schwann cells are also phagocytesfor debris. They are vital to regeneration of damaged peripheral nerve fibers. -The space bt 2 neighboring Schwann cells is node of Ranvier. -nodes are unmyelinated -neurilemma: outermost covering of schwann cell

olfaction

sense of smell. closely associated w the sense of taste. -contributes to 80% of our taste of food. If nose is blocked, food tastes bland .•olfaction relies on chemoreceptors that detect dissolved chemicals .•The olfactory receptors are imbedded in a yellow patch of olfactory epithelium (organ of smell)found in the roof of the nasal cavity, covers superior nasal conchae. As air enters the nose, most of it directly heads for the air passages. This is why that a little of the air shunted to the olfactory epithelium. That is why you can detect better w sniffing, as the sniffing directs more air toward the smell receptors in the olfactory epithelium. olfactory hairs that project into the layer of mucus covering the olfactory epithelium. Chemicals to be smelled must be in a gaseous state and able to be dissolved in the mucus covering the olfactory epithelium. These chemicals stimulate the hairs (olfactory neurons which are unusual bipolar neurons) & generate an AP, which travels up the filaments of the olfactory nerve, through the cribriform plate in the ethmoid bone, and synapse in the olfactory bulb. The neurons of the olfactory bulb then travel up the olfactory tracts to the brain to be interpreted.

olfactory nerve

sensory consists of tiny neurons that run from the olfactory receptors in the nose through the cribriform plate to connect w/ olfactory bulbs different from olfactory tract function: smell imbalance: loss of smell

optic nerve

sensory function: brings visual stimuli into the brain, afferent impulse for vision imbalance: blindness don't confuse w/ optic tract

vestibulocochlear nerve

sensory function: hearing & balance imbalance: deafness, loss of balance

pons

sensory & motor tracts run thru here. Also contains 2 respiratory centers that work w those in the medulla.

central sulcus

separated frontal and parietal lobe -precentral/ primary moto & post central/ somatosensory gyri are on either sides of central sulcus

lateral sulcus

separated the temporal lobe from the frontal and parietal lobes

parieto-occipital sulcus

separates parietal lobe from occipital lobe

potential difference

separation of charges Immediately inside the membrane of a cell is (-) charged while immediately outside the membrane of a cell is (+) charged. Because opposite charges are attracted to each other, energy must be used to keep the charges separated

blister

seperation of dermis and epiderm.

lateral ventricles

septum pellucidum separates the 2 lateral ventricles. Through a tiny pore called the interventricular foramen (foramen of Monro), ea lateral ventricle is connected to the 3rd ventricle.

nerve

several bundles of axons, with their accompanying tissues (connective sheaths & blood vessels), that lies outside the brain & spinal cord, and transmit sensations to the CNS, and impulses from the CNS to muscles & organs. group of axons together w/in PNS

diaphysis

shaft or region of long bone 0made of compact bone surrounding medullary cavity

parts of hair

shaft: protrudes above the skin (keratinized). root: -The portion that anchors hair to the skin -The shaft & root are composed of column of dead, keratinized epithelial cells -arranged in concentric layers: medulla, cortex, & cuticle. hair follicle: -Organ that produces hair (embedded in the dermis). -It is an infolding of the epidermis known -outer component anchors the follicle to the dermis & the inner component is anchored to the hair root. 4. hair bulb the base of the root is expanded to form the hair bulb. Basically, hair bulb is the root and the papilla.• hair matrix: -undifferentiated epithelial cells, -inside the hair bulb which differentiate into keratinocyte, mixed with some melanocytes. Matrix produces the hair.• Papilla of the hair: -at the base of the hair bulb -contains the blood vessels feeding the cells of the matrix.

twitch contraction

simplest contraction resulting from a muscle fiber's response to a single action potential from motor neuron. phases of muscle twitch Three phases of muscle twitch 1. Latent period: events of excitation-contraction coupling •No muscle tension seen 2. Period of contraction: cross bridge formation•Tension increases 3. Period of relaxation: Ca2+ reentry into SR •Tension declines to zero •Muscle contracts faster than it relaxes

insula

small mass of cortex deep to the lateral sulcus, made visible only by retracting or cutting away some of the overlying cerebrum. function: emotion, taste, integrating sensory info from visceral receptors (ex. full bladder)

sarcomeres

smallest function unit of muscle cell -distance bt. two 2 lines -10,000 myofibril in 1 sarcomere consists of 1. thick filament 2. thin filament 3. proteins that stabilize the position of thin and thick filaments (ex. tinin) 4. proteins that regulate interaction bt. thick and tin filaments

solvent vs solute

solute is dissolved by the solvent ex. solvent= water, solute= soap

hypotonic

solution with more solutes outside than inside the cell -water moves in cell

Hypertonic

solution with more solutes outside that inside the cell than inside -water moves out of cell

loudness

sound is coded by the number of hair cells stimulated. Our brains only hear the louder ear. If a low sound is applied to the left ear & a louder to the right, we only hear the right ear.

graded potential

starts signaling in sensory nerves -in dendrites -if threshold is reached via summation w. other graded potentions AP is triggered -short lived -can be depolarizing (-70mv to -65mv aka less negative) or hyperpolarizing (-70 to -75mv aka more negative) -occurs when stimulus causes mechanically gated or ligand gated channels to open or close in plamsa membrane useful for short distance communications. However, a graded potential can become stronger & last longer by summation with other graded potentials.

sleep

state of changed consciousness from which a person can be aroused (as opposed to COMA) 1. pre-sleep: your brain shows beta waves means you are alert, eyes move rapidly, have muscle tension. This is followed by alpha waves which means you are still awake but relaxed & getting ready for NREM .2. Non-REM (NREM) (nonrapid eye movement) 3. REM (rapid eye movement) We cycle back & forth bt REM & NREM during the course of the night.

Hippocampus

storage & retrieval of long-term memories.

autonomic nervous system

supplies motor input to heart muscle, smooth muscle cells of blood vessels, intestines, and glands sensory system: has sensory receptors (i.e, interoceptors) that send information (perception) i.e, changes in bp, through ascending afferent circuits to the hypothalamus, brain stem, spinal cord. motor system: commands for a type of behavior (as opposed to the sensory perception) which is sent thru descending efferent circuits to the motor endings serving effectors (cardiac & smooth muscle). ANS is the involuntary part of the PNS.

lumbar plexus

supplies the skin of the thigh as well as the FEMORAL NERVE (the largest nerve of the lumbar plexus, and supplies the thigh & knee).

stretch reflex

takes place when muscle spindles in a muscle are suddenly stretched The reflex contraction of a muscle when it is stretched. Special sensory receptors (called proprioceptors) in muscle cells constantly monitor the state of muscles. The stretch reflex, by limiting its range of movement, protects a muscle from being overstretched and damaged. However, this protective mechanism can itself be damaging if the muscle is lengthened suddenly, especially when cold. The muscle will automatically and forcibly try to shorten, sometimes rupturing itself. For this reason, sports coaches usually advise exercisers training for flexibility to perform static stretches, or slow, controlled movements. All stretch reflexes are monosynaptic (direct communication bt sensory and motor neuron) and ipsilateral (same side).

osmotic pressure

the external pressure that solutes exert that must be applied to stop osmosis/ water movement

insertion of muscle

the movable attachment. Thus when the muscle contracts it pulls on its insertion to move the bone in a specific direction.

isotonic contraction

the tension in the muscle remains constant as the muscle length shortens. Therefore, if you do isotonic exercise such as jogging, swimming, weightlifting, your muscles contract and bring about movement. This is aerobic exercise (strengthen heart & respiratory muscles).•

static equilibrium

the utricle & saccule each contain a thickened region of epithelium called the macula (thickened area). The macula contain hair cell receptors that are concerned w static equilibrium, and thus provide information about the position of the head in space. The 2 macula lie at right angles to ea other.....the macula in the UTRICLE is oriented horizontally, so it gives info about HORIZONTAL motion. For example, when tilting the head. macula in the SACCULE is oriented vertically, so it gives info about VERTICAL motion (like going up in an elevator). When the head moves vertically, the sensory cells of the saccule are disturbed and the neurons connected to them begin transmitting impulses to the brain. •Sitting on top of ea macula is a membrane containing small "stones" called OTOLITHS. •As an analogy, think of otoliths as a plate sitting on a greased cookie sheet. When the cookie sheet is tipped, the plate slides to the side. In the same manner, when the head is Tipped to one side, the otoliths slide across the macula & pull on the hair cells, making these receptors fire. This information is sent to the brain via the vestibulocochlear nerve, and we are able to correct our tipped position.

Periosteum

the vascular connective tissue membrane that surrounds bone. (outside bone)

sensory neurons

their cell bodies (somas) in ganglia outside the CNS

hypothalamus

thirst, hunger, body temp, sexual drive regulator.

anterior segment of eye

this is the area in front of the lens/suspensory ligament, and includes the areas in front of & behind the iris. -filled with aqueous humor

posterior segment

this is the region bt the lens/suspensory ligaments & the retina. -filled with VITREOUS HUMOR, this is the region bt the lens/suspensory ligaments & the retina.

meninges

three protective membranes that surround the brain and spinal cord has 3 layers a. dura mater b. arachnoid mater c. pia mater

inner hair cells

transform the sound vibrations in the fluids of the cochlea into electrical signals that are then relayed via the auditory nerve to the auditory brainstem and to the auditory cortex.

motor neurons

transmit impulses from the CNS out to the effector muscles or glands.

denticulate ligaments

triangular-shaped membranous extensions of the pia mater that secure the spinal cord to dura mater. They are basically thickening of the pia mater. They project laterally & fuse w the arachnoid mater & the inner surface of the dura mater bt the anterior & posterior nerve roots of spinal nerves on either side.

afferent vs efferent

under PNS afferent (sensory) : nerve brings bring into TO brain and spine efferent (motor): carry into from the CNS OUT to muscles and glands

gray matter

unmyelinated axon & the cell vody

tarsal plate

upper eyelid connective tissue sheet that gives support to the eyelid. Some muscles, i.e, orbicularis oculi, also attach to the tarsal plate.

cribiform plate of ethmoid bone

upper part of the ethmoid bone, forms the roof of the nasal cavity. It contains lots of tiny holes. Olfactory nerve fibers pass thru the cribriform plate to get to the brain. This plate has a median vertical projection called crista galli (rooster's comb) that anchors the cranial meninges.

yellow marrow

used to be red marrow -due to age

perpendicular plate

vertical median bone that becomes part of the nasal septum. Coming in from the lateral sides are 2 coiled areas called the superior & medial conchae, which are the nasal turbinates. These serve to increase the surface area within the nose to better provide for warming air when inhaled.

neurons in spinal cord

very front of ventral horn had interneurons recieving input from somatic sensory neurons very back of dorsal horn has somatic motor neurons middle has visceral motor & sensory neuron

special senses

vision, hearing, taste, smell, equilibrium, touch

cataract

w age, the lens becomes cloudy. Lens can be surgically replaced. However, the new lens is not attached to the suspensory ligaments, so there is no accommodation & the person still has presbyopia.

presbyopia

w age, the lens loses its flexibility, making it more difficult to accommodate for near vision. This is why Older people hold things farther away from their eyes to focus on them.....their lenses can no longer pull the image up from behind their eyeballs, so they have to move the object farther away.

summation

when 2 graded potentials add togehter

parathyroid hormone

when a drop in blood Ca concentration (level), PTH stimulates osteoclasts to release calcium from the bones into blood.

intrinsic muscle

when both origin & insertion (the entire muscle) are within the same organ, i.e, tongue.

reflection of light

when light bounces off an object bouncing off the surface, and we see things because light has been reflected off objects. If an object reflects all frequencies of light, we see it as white.

medial and lateral canthus

where eyelids meet at corner of eyes

3 parts of ear

•1. outer (external) ear: hearing only consists of auricle (pinna): The pinna is the folds of cartilage surrounding the ear canal. In some animals with mobile pinnae (like the horse), each pinna can be aimed independently to better receive the sound. For these animals, the pinnae help localize the direction of the sound source. Human beings localize sound within the central nervous system, by comparing loudness from each ear in brain circuits that are connected to both ears. external auditory canal (external auditory meatus): lined w skin that contains ceruminous glands. tympanic membrane (ear drum). separates the outer ear from the middle ear. •2. middle ear: hearing only air-filled, mucous membrane lined cavity w/in the temporal bone. One wall is made up of the tympanic membrane, while the opposite wall contains 2 membrane-covered openings: the oval (vestibular) window and the round (cochlear) window. Between the tympanic membrane and the windows are 3 tiny bones (ear ossicles): the malleus (hammer), incus (anvil) and stapes(stirrup). The eustachian (auditory) tube connects the middle ear to the nasopharynx & permits air to enter or leave the middle ear cavity. The air pressure in the middle ear must be the same as the external atmosphere pressure for the eardrum to vibrate properly. Ex: swallowing or yawning creates the "pop" by opening the eustachian tubes & equalizing the air pressure. •3. inner (internal) ear: hearing & equilibrium bony labyrinth (cavity) w/in the temporal bone that contains a structure called the membranous labyrinth. The "membranous labyrinth" includes the true receptor organ of hearing (the coiled cochlea), the utricle and saccule (the organs of static equilibrium) and the semicircular canals (the organ for dynamic equilibrium). A fluid called endolymph fills the vestibule (utricle & saccule), and the cochlear duct (scala media) while perilymphfills the cochlea.

types of deadness

•1. sensorineural deafness: due to damage to any of the neural structures involved w hearing, from the cochlea or the vestibulocochlear nerve to the auditory cortex of the brain located in the temporal cortex. .•2. conductive deafness: due to problem w the conduction of sound along its pathway. It may include lots of wax in the external auditory canal, a ruptured eardrum, damage to the ear ossicles, arthritis of the auditory bones, middle ear infection in which fluid fills the middle air cavity (replaces air), etc.

factors influencing the force of muscle contration

•1. the number of muscle fibers stimulated •2. the size of the fibers: the bulkier the muscle, the more tension it can develop. •3. the frequency of stimulation. •4. the degree of muscle stretch: the best stretch is when stretched to slightly over 100% of its resting length (lets say 120%). •In general, optimal sarcomere operating length is 80%-120% of resting length. If you increase the length of sarcomere to 170% it is excessively stretched. Similarly, if sarcomere is lets say at 75% stretch of its resting length, force generation is limited due to too much overlap of filaments.

smell pathology

•Anosmia: inability to perceive odors. •Hyposmia: decreased the ability to smell. •Hyperosmia: increased ability to smell. •Anosmia may be the result of injury to the olfactory nerve, nasal cavity congestion (i.e, like a cold), or Zn deficiency (Zn is required for regrowth of the olfactory epithelium).

Brain Hemispheres

•Each brain hemisphere is concerned w the opposite (CONTRALATERAL l side) of the body. (Right to Left & Left brain to right body side.) •hemispheres are not entirely equal in nature. LATERALIZATION (specialization) of cortical function can occur in only one hemisphere. R side: controls emotion, intuition, artistic skills L side: controls language, math, logic

movement descriptions

•Flexion/extension of a joint (bend/straighten) •Abduction/adduction of a limb (move away/move toward body) •Supination/pronation (in the hands, turn palm up/turn palm down) •Inversion/eversion (refers to feet; turn sole of foot faces medially/sole of foot faces laterally)

motor units

•Motor unit: a single motor neuron & all the muscle fibers (muscle cells) it supplies. Thus, firing of a motor neuron will lead to stimulation (contraction) of all the single muscle cells (fibers) that the motor neuron innervates •Small vs large motor units: •Small motor unit: only a few muscle fibers innervated by a single motor neuron, i.e, eye muscles or fingers muscles, where as in large muscles like in your arms, or legs designed for gross movements, have large motor units. •Large motor unit: lots of muscle fibers are connected

nail

•Nail: is a thin plate, consisting of layers of dead stratum corneum cells that contain a very hard type of keratin. Analogous to claws. Pink color due to blood flow (Hb).