Unit 2 lab Flashcards
Nerve plexuses
Branching/ intersecting nerve fibers that deal w/ (mostly) voluntary/ somatic sensation and movement
Where do nerve plexuses come from?
Spinal nerves
Spinal nerves
Separate into smaller branches (rami)
- dorsal ramus
-Ventral ramus
- rami communications
- meningeal branch
Dorsal ramus (spinal nerves)
Goes to targets in dorsal (back) areas, to supply areas in that region
Ventral ramus (spinal nerves)
Goes to targets n the ventral (front) areas; in thoracic regions, become intercostal nerves
Rami communicates ( spinal nerves)
Go to ANS in thoracic regions (do not merge into plexi)
Meningeal Branch (spinal nerves)
Loops to vertebra area, to meninges, n some regions
In thoracic region the ventral rami___
(Spinal nerves)
Do not make plexi
In rest of regions, what does ventral rami make?
(Spinal nerves)
Make plexi
What does plexi form from? (Nerve plexus)
Form from the ventral/ anterior rami of spinal nerves (no dorsal rami)
Purpose of nerve plexus
Different spinal nerves are sorted and recombined, so all fibers going to a specific body part are put together in one nerve
Advantage of nerve plexus
If there is damage to one spinal nerve, it does not eliminate all functions in one limb
How many plexi originating from spinal cord?
Multiple plexi
Most spinal nerves converge into a plexi, except___
Except spinal nerves T2- T11
What are T2-T11?
Intercostal nerves and do not converge because each nerve projects along one rib
Is there sharing of branches of spinal nerves?
Some sharing between plexi
Most afferent and efferent fibers in the plexus deal w/?
Voluntary functions but there are few exceptions
What does cervical plexus supply?
Supply skin in upper regions and control diaphragm
What discs makeup cervical plexus ?
C1-C4 (small contribution of C5 )
C1-C4(C5) supply?
(Cervical plexes)
Supply sensory fibers to the skin of neck, ears, head, shoulders, one big exception
Exception of cervical plexus?
Phrenic nerve
Phrenic nerve (cervical plexus)
Supplies motor and sensory fibers to the diaphragm, the chief breathing muscle
What discs keep diaphragm alive?
C3, C4,C5
Brachial plexus
Give rise to nerves supplying the upper limb
What discs makeup brachial plexus?
C5- C8 + TI
What small fibers are received? (Brachial plexes)
From c4 and T2
Branching system of brachial plexus?
Roots (rami) → trunks → divisions → cords → branches
Divisions (brachial plexus)
Arrange motor neurons to anterior/posterior
- fibers of motor neurons direct to an anterior/ posterior compartment of arm
Anterior compartment of division (brachial)
Flexor innovation, flexion movement
Posterior compartment of division (brachial)
Extensor innovation, extension movement
Roots (brachial)
Five vertebral rami ( c5 -t1)
Trunks (brachial)
Upper, middle, and lower
Divisions (brachial)
3 anterior and 3 posterior
Cords (brachial)
Lateral, medial, posterior
What do anterior/posterior fibers target?
- Anterior Targets front of limb
- posterior targets back of limb
Cords rebranch into… (Brachial)
Into nerves that go to their targets
Cords branch into primary… (Brachial)
Primary terminal nerves
- smaller nerves also branch earlier from divisions
- “m”
-Posterior cord
Formation of “m” (branch)
3 nerves branch from lateral / medial
- musculocutaneous, median, and ulnar nerves are more anterior and superficial
2 nerves branch from posterior cord (brachial)
Radial and axillary nerves are more posterior and deep, above humerus
Are there earlier nerve branches? (Brachial)
Earner never branches coming from early points
Is brachial plexus short?
Relatively short, w/the branched nerves stretching to targets in arm
Motor neurons (brachial)
Send axons through these nerves and target these muscles for somatic control
Sensory axons (brachial)
- Travel in from propriocepturs of same muscles, tendons, joint regions
- trawl in from general senses receptors from these regions too, including skin
Axillarg nerve (brachial)
Branch Off from posterior cord
- target shoulder joint, deltoid muscles, and teres minor muscles
Radial nerve (brachial)
Branches off from posterior cord wraps around humorous
- targets: posterior skin of limb
Elbow, muscles that supinate forearm
Extensor muscles of upper arm
Extend hand and fingers
Abduct thumb
Common injuries of radial nerve
Wrist drop: can’t extend hand
Muscular cutaneous nerve
Branches off from lateral cord moves inferior in the anterior arm
- targets:
Biceps muscle
Brachialis muscles
Cutaneous sensation in lateral forearm
Ulnar nerve
Branches off from the media cord, swinging superficially and posterior to elbow, then follows the ulna
- targets:
Flexor is not supplied by median nerve
Intrinsic hand, muscles and skin
Cause his hand and fingers to flex
Helps abduct/addictmedial fingers
Common injuries of ulnar nerve
-Funny bone -easy to hit
-Claw hand -difficulty gripping
Median nerve
Forms from both the media cord and lateral cord, descends through the anterior forearm
Targets:
Flexor muscle
5 intrinsic muscles of lateral palm
Pronation of forearm
Causes hand and fingers to flex.
Common injuries of median nerve
Carpal tunnel syndrome
Pinching difficulty
What do lumber plexus and sacral plexus overlap through?
L4 spinal nerve
What nerves make up sciatic nerve
Lumbar and sacral root
Lumbosacral trunk
Where fibers of lumbar plexus (L4) contribute to sacral Plex
Sciatic nerve
Common fibular + tibial nerve in common sheath
Longest, and thickest nerve fiber in the body
What discs makeup the lumbar plexus?
L1-L4(Some L5)
Where do the major branches innervate of the lumbar plexus?
Anterior and medial thigh(upper limb)
Femoral Nerve (Lumbar Plexus)
Innervates primary thigh flexors+ extensors (quadriceps)
-move more anteriorly through groin
-supplies, cutaneous branches to skin in anterior thigh, for sensory reception,
Common injury of femoral nerve (lumbar plexus)
Gait / walking problems when injured
Obturator nerve (lumbar plexus)
Nerve moves medially to inner thigh
- innervates primary thigh adductors that helped to control motor neurons that are responsible for side to side motion
-Supply general sensory reception from inner hip and knee joints, as well as medial thigh
Common injury of obturator nerve (lumbar plexus)
Thigh numbness
Saphenous nerve (lumbar plexus )
Important branch of femoral nerve
-Goes, below the knee by passing by the hip joint to knee, to foot
-Primarily involves cutaneous sensory input
What discs supply sacral plexus?
L4 - L5, S1-S4
Supplied thigh/leg , buttocks , pelvic area
Sacral plexus
Includes lumbosacral trunk
-12 major branches supplied thighs/leg buttocks, pelvis, and perineum
- caudal (below) lumbar plexus
-Supply whole lower limb, except anterior medial thigh, including major muscles like thigh extensors and leg flexors
Two nerves in one sheath in sacral plexus
① Tibial nerve L4-5, S1-3
② Common fibular L4-5, S1-2
Branches of sciatic nerve
‘Below the knee
-Common fibular = anterior
- tibia = posterior
What happens after division of sacral plexus separate in common fibula and tibial nerves?
Merge in sciatic nerve then rebranch above knee, switch their compartments
Why do the branches of sacral plexus switch?
Lower limb is inverted compared to upper limb, relative to spinal cord
- extensor innovation, extension
- flexor Innervation, flexion
Sacral, plexus, flexor innervation
- Supplied by tibial
- must be on posterior of lower leg
Sacred plexus, extensor innervation
- Supplied by common fibular
- must be on anterior of lower leg
Tibial nerve of sacral plexus
Targets compartment muscles of leg and skin of posterior calf and sole of foot
- supply posterior of limb, branches into plantar branches (medial and lateral)
Plantar branches of sacral plexus
Deal w/ sensation and targets in sole of foot
Common fibular nerve of sacral plexus
Descends and wraps around fibula, and target more anterior and lateral parts of leg
- also target top of foot for dealing w/ cutaneous sensation
- deal w/ motor movements in dorisflexion of foot and extension of toes
Pudendal sacral plexus
Targets perineum and a variety of muscles in area
- supply regions w/ sensory neurons that stimulate erection
- motor neurons help control urination
Superior gluteal and inferior gluteal of sacral plexus
Head to both the gluteus muscle and cutaneous regions
Cranial nerves that function in parasympathetic division
Oculomotor, facial, glossopharyngeal, vagus
Where do sensory neurons wire in autonomic nervous system?
Wire to brainstem and diencephalon
What does ANS spirt into?
Parasympathetic and sympathetic
Dual innovation
Both divisions wire to same targets
Parasympathetic and sympathetic divisions have opposing____
Opposing stimulator and inhibitory function
Parasympathetic division
“Rest and digest”
- keep energy use low and direct vital “housekeeping” activities like digestion, urination, and basal heart/ breathing rates
Sympathetic division
“Fight or flight”
- mobilizes during activity, stress, emergency situations, triggering changes needed for rapid response and decreasing nonessential processes
What targets does the ANS control?
- Smooth muscle (organs and vessels)
- cardiac muscle (heart contraction)
- glands (endocrine system)
Somatic nervous system has _ neuron chain
1
ANS has a _ neuron chain w/ _
2 neuron chain w/ ganglia
Parasympathetic and sympathetic division postganglionic cells use different ___
Neurotransmitters
- ACH - nicotinic
- ACH - muscarinic
- NE - adrenergic
ACH - nicotinic (neurotransmitters)
Always stimulatory
-Dendrites of postganglionic cells
-Skeletal muscles sarcolemma
-Adrenal medulla
ACH - muscarinic (neurotransmitters)
Either stimulatory or inhibitory, depending on the sub class of receptor in target
-All parasympathetic targets
NE - adrenergic ( neurotransmitters)
Either stimulatory or inhibitory, depending on the sub class of receptor in target
-All sympathetic targets
What does ganglia allow for ANS?
Allow for points of interaction and branching from various regions of body
- different areas respond to each other and control multiple organs for response
What switches does ganglia allow? ( ANS)
Stimulator and inhibitory switches n the circuit logic, important for balancing responses
Parasympathetic division; “circuit conformation”
① origin: cranial nerves and one area sacral spinal cord
② long preganglion neurons short postganglioh neurons
③ ganglia are near their target effector organ
Vagus ( CNX ) nerve (parasympathetic)
Branches account for 90% of the preganglionic nerves in this system
Oculomotor ( CN 111) nerve ( parasympathetic)
Deals w/ constriction of eye when light is detected, and to assist focus
Facial and glossopharyngal nerves (parasympathetic)
Deal w/ innervating and triggering the salivary glands
Sacral nerves (parasympathetic)
Send preganglianic neurons to pelvic regions
(Include S2 and S4 )
Sympathetic division: “circuit conformation”
① origin: thoracic and lumbar regions of spinal cord
② short preganglion neurons long postganglion neurons
③ ganglia are near the spinal cord
Ganglia are near the ____ in sympathetic
Near spinal cord in sympathetic chain ganglia pattern due to their form, link fibers to each other
In thoracic area, ave cell bodies of the sympathetic neurons In lateral horn?
Yes - provide cell bodies for motor neurons in sympathetic system
Ganglia provides? (Sympathetic)
Provide interaction areas, where postganglionic neurons can head in many different
Possible paths of neurons (sympathetic) ①
Synapse in trunk ganglion at same level as spinal nerve
② possible path
Synapse in trunk ganglion at higher or lower level
③ possible path
Bypass trunk ganglion through specialized splanchnic nerve, which will then synapse at a collateral ganglion
① synapse in a trunk ganglion at same level pathway
Entry is white ramus communicant for preganglion axons into sympathetic trunk ganglia
- synapse w/ postganglion neuron in ganglia at same level
- gray ramus communicant is exit for postganglion, reenter spinal nerve to effector
② synapse in a-trunk ganglion at higher/ lower level pathway
Enter through white ramus (preganglion) into sympathetic trunk ganglia
- preganglion neuron does not synapse in ganglia at same level
- preganglion goes ↑ or ↓ think to other ganglia, synapse w/ post ganglion neuron then exit gray ramus
③ go through splanchnic nerve to collateral ganglion pathway
-pre-ganglion axons passed through the sympathetic trunk without synapsing
-pre-ganglion neuron instead forms a splanchnic nerve that synapse with other collateral ganglion, which are closer to effectors
-Synapse with post ganglion neurons that go to targets
Sympathetic nerves do not leave _
Gray communicants
Some sympathetic trunk ganglion have nerves that go___ to effectors
Directly to effectors from the ganglion
Post ganglion axons_ exit the gray ramus communicants and the spinal nerve
Do not
Post ganglion neuron forms a
Sympathetic nerve that sends axon straight to the effect or organ via a separate and unique pathway
Special pathway of sympathetic neuron
Some connections are made in which there is no formal ganglion
-pre-ganglion neuron go directly to chromaffin cells in adrenal gland
- onromaffin secrete Norepinephrine or epinephrine into bloodstream to illicit responses via the endocrine system
Nervous system
High-speed electrical signals along specialized neurons
-signals regulate or control other cells
-fast responses needed due to changing environment
-somatic, and autonomic nervous
Endocrine system
Secrete hormones that coordinate lower but longer acting responses, including
-reproduction, development, growth, metabolism, behavior, and immunity
Endocrine glands
Ductless glands that produce hormones and like ducks
-release hormones into surrounding fluid
-rich, vascular
-branching networks
-pituitary, thyroid, parathyroid, adrenal, and penal glands
Organs
Several organs also have special subdivisions of secretary, endocrine cells
-pancreas, go nuts and placenta
Gland
Group of cells that secrete one or more products generally begin as a epithelial tissue
Glance can be activated via three mechanisms
Humoral stimulus neural stimulus and hormonal stimulus
Humoral stimulus
Some perform on sensing/response
Normal stimulus
Can be directly wired to the ANS
Hormonal stimulus
Many are regulated by hormones from other glands
Hypothalamus exerts effects on the…
Endocrine system via the pituitary gland
Hypothalamus is a nerve center which receive
Receive neuron signals and releases neural hormones via neural secretary cells
How does hypothalamus instruct the adjacent pituitary gland?
Instructs the pituitary gland to then release hormones into the body
-posterior, and anterior pituitary gland
Posterior pituitary gland
Stores and secrete hormones that are made first in the hypothalamus
-not a true endocrine gland since it doesn’t make its own hormones
What does posterior pituitary gland store?
Stores hormones that are ready ready made from the hypothalamus
-oxytocin and ADH
Oxytocin and ADH are almost identical structure
True but yield in very different effects
Anterior pituitary gland
Makes and releases its own hormones, but still under control hypothalamus
-true endocrine gland
How does anterior pituitary gland respond to hypothalamus
Respond to hypothalamus hormones by making and releasing own hormones
-growth hormone TSH, acth, fsh, lh, prolactin
Does anterior , pituitary gland, secrete, both tropic and tropic hormones
Yes
Tropic hormones
Exert effects on other glands in the endocrine system
-promote forming of other growth hormones, include IGFs
Non-tropic hormones
The anterior pituitary also secretes some hormones that act directly on non-endocrine cells
-act directly on cells to change metabolism
Growth hormones is an example with both…
Direct non-tropic and indirect tropic effects
Anterior gland is activated by
Hypothalamus hormones
Posterior gland is activated by
Neural stimulus
Thyroid gland
Critical role in regulating metabolism
-Butterfly shaped gland located below Adams apple
Thyroid hormone of thyroid gland
Target, every cell in the body is a target
-Metabolism
-control rate glucose is burned
-help maintain blood pressure
-important for tissue growth/development
Need iodine in diet for TH
Calcitonin of thyroid gland
Decreases blood CA2 plus levels when gets high
Target =inhibits osteoplast bone breakers
Follicles of thyroid gland
Hollow structures and thyroid
Have internal space lumen that stores thyroid hormone in a globulin form and iodine mixture together called a colloid
Follicular cells of thyroid gland
Line the follicles are the cells that produce thyroid hormone, allowing it to be stored in the adjacent moment
Parafollicular cells of thyroid
Are also present, but not around the colloid. These are the cells that secrete calcitonin.
Where is thyroid gland under control from?
Pituitary gland
Parathyroid gland
Regulates calcium levels
Four glands on the posterior surface of the thyroid gland, some in other neck regions
—
Parathyroid hormone PTH
Low blood calcium levels will increase PTH which increases calcium level in the blood
-target= stimulates osteoplast-leads to the breaking down of bones
-stimulates the kidneys to absorb more calcium
Are calcitonin and PTH antagonist
Yes
What do parathyroid cells form?
Form thick mass of non-follicle tissue, which can be easily distinguished inside by side comparisons
Parathyroid gland functions via
Humoral stimulus
Pineal gland
Small pinecone gland thoroughly is melatonin
-Located in brains third ventricle
-melatonin is secreted based in response to visual pathways
-melatonin helps regulate sleep cycle and timing of sexual maturity
Pinealocytes are cells that’s secrete (penal gland
That’s secret melatonin
-Distinctive landmarks and tissue of the penal gland is a penal sound
Pineal sand
Corpora arenacea
- accumulates with age and can be used to orient brain scan images
-Deposits of calcium and salts that are of lar function, but due limit production of melatonin with age
What stimulus from hypothalamus in penal gland?
Neural stimulus
Thymus gland
Involved in producing lymphocytes(immune system)
-located in upper thorax posterior to sternum connected to lymphatic system
What does thymus gland secrete?
Secretes thymosin, thymus in, thymopoitens which act locally(paracrine) which helps thymus act as an incubator for immune system T cells
What is thymus replaced with?
Replaced with fibrous and fatty tissue overtime, but it continues making immune cells
Cortex of thymus gland
Darker outer area of each lobe which contains large amounts of immature lymphocytes
Medulla of thymus gland
Lighter inner areas made of epithelial cells were mature, lymphocytes stored
Pancreas
Organ that also secretes hormones to regulate blood glucose levels
-exocrine and endocrine function
Hormone secreting cells in pancreas
Pancreatic islets
Beta cells (pancreas)
Secrete the hormone insulin
- signals cells to take up more circulatory glucose reducing blood glucose levels
Alpha cells (pancreas)
Secrete hormone glucagon
- antagonist to insulin causing glucose release from liver to raise blood sugar
Are beta and alpha cells more or less numerous
Beta cells= more numerous
Alpha cells = less hormones
Delta cells (pancreas )
Secrete somatostatin which inhibit growth hormones
Acinar cells (pancreas)
Outside of pancreatic islets, they produce enzyme rich digestive juices
How is negative feedback loop maintained through the pancreas
Via many different activation pathways
Pancreas can be activated via 3 mechanisms
Humoral, neural, and hormonal stimulus
Humoral stimulus (pancreas)
Blood glucose directly sensed from islet cells, and paracrine response
Neural stimulus (pancreas)
Dual innervation from parasympathetic and sympathetic divisions
Hormonal stimulus (pancreas)
GH binds delay cells in negative feedback loop to make somatostatin
Adrenal glands different layers with different stimulus and hormones
Medulla and cortex
Medulla (adrenal glands) water soluble
Neural stimulus by ANS releases epinephrine and norepinephrine
Cortex (adrenal glands) lipid soluble
Hormonal stimulus by either the hypothalamus, kidney, heart
- glucocorticoid, sex steroid (androgen)
humoral stimulus directly into the zona glomerosa
- mineralocorticoids
Zona glomerulosa
Mineralocorticoids (aldosterone) that balance minerals in blood
Zona fasciculata
Glucocorticoids (cortisone/cortisol) long term stress/inflammation
Zona reticularis
Weak androgens/gonadocorticoids to be made into sex hormones
Adrenal medulla
Norepinephrine and epinephrine
Chromaffin cells (adrenal medulla)
Secrete hormones into medulla veins
What do chromaffin cells release
Neurosecretiry release hormones in response to ANS
-arranged in clusters around veins with granules in cytoplasm due to high vesicles number
NE/E activates … (adrenal medulla)
Short term stress responses
Sympathetic activation short term (adrenal medulla)
Hypothalamus communicates via
- direct neural connections via
- sympathetic division of ANS to adrenal medulla
- releases NE/E
Glucocorticoids hormones secreted by
Zona fasciculata of adrenal gland
- include cortisol, cortisone and corticosterone
Is only cortisol made in significant quantities
Yes within human body
Is cortisol lipid soluble
Yes like all adrenal cortex hormones, and is a steroid
Cortisol has both
Normal conditions responses
Chronic emergency responses
Where is cortisol normally regulated from
Hypothalamus and is therefore tied to circadian clock cycles
Process of cortisol regulated by hypothalamus
Hypothalamus signals A pituitary gland
- A pituitary secretes ACTH
- ACTH stimulates zona fasciculata
- cortisol’s releases by adrenal cortex
What does cortisol normally prevent
Hypoglycemia (low blood sugar)
- promotes gluconeogenesis, getting sugars from non carbohydrate sources to get energy for brain
- breakdown fat (lipolysis
- protein breakdown
Cortisol is secreted throughout the day with a
Predictable circadian rhythm
Cortisol levels normally kept in check so
Too much tissues are broken down
Cortisol levels are kept in check by
Negative feedback loops
Long term stress/ inflammation cortisol
Stresssors will interrupt normal cortisol rhythm by providing constant stimulus that bypasses negative feedback loops by continuously activating hypothalamus
- leads to chronic elevation of cortisol in bloodstream
Chronic elevation of cortisol in bloodstream..
Due to long term stress can have many problematic effects
- gluconeogenesis will degrade tissues, due to starvation stress
- immune system/ inflammatory response is suppressed in order to save energy
Mineralocorticoids hormones
Secreted by zona glomerculosa of adrenal gland
- mainly aldosterone has variety of func. And targets that require regulation of ion balances
Mineralocorticoids hormones has control over
Na/K balances in body
Blood presse control
Water movement (kidneys)
Electrolyte balance (neurons)
Ovaries
Produce estrogen and progesterone
Estrogen
Produced by Graafian follicles and promote development of secondary sexual characteristics
- large role in menstrual cycle and milk production
Progesterone
Secreted by corpus luteum
Testes
Produce testosterone
Testosterone
Most important of androgems asecreted by testes
- cause development of male sex characteristics
- necessary for continued production of sperm
What is a Plexus?
A plexus is a network of intersecting nerves.
What are the different branches of the Spinal Nerves?
The different branches of the spinal nerves include ventral rami and dorsal rami.
What branches of Spinal Nerves contribute to plexi?
The ventral rami branches of spinal nerves contribute to plexi.
Plexus Roots = Ventral Rami branches of Spinal Nerves!
Where are plexi found in the body?
Plexi are found in various regions of the body, but they are NOT found in the thoracic region.
What are the advantages to having afferents and efferents organized into plexi?
The organization into plexi allows for more complex and coordinated nerve function.
Which Spinal Nerves contribute to the Cervical Plexus?
The cervical plexus is formed by the ventral rami of C1 to C4 spinal nerves.
Which Spinal Nerves contribute to the Brachial Plexus?
The brachial plexus is formed by the ventral rami of C5 to T1 spinal nerves.
What important role does the Cervical Plexus play, with regard to ‘staying alive’?
The cervical plexus plays a crucial role in innervating the diaphragm through the phrenic nerve.
Be able to identify the Phrenic Nerve.
The phrenic nerve is a major nerve of the cervical plexus that innervates the diaphragm.
Which Cranial Nerve contributes a small portion to the Cervical Plexus?
The accessory nerve (Cranial Nerve XI) contributes a small portion to the cervical plexus.
Know the different levels of organization of Brachial Plexus.
The levels of organization of the brachial plexus are: Roots > Trunks > Divisions > Cords > Branches (of ‘Terminal’ Nerves).
Know the major ‘Terminal’ Nerves of the Brachial Plexus.
The major ‘Terminal’ Nerves of the brachial plexus include the ulnar, median, and axillary nerves.
Know which Cords the ‘Terminal’ Nerves are derived from.
The ‘Terminal’ Nerves are derived from the lateral, posterior, and medial cords of the brachial plexus.
Know what injuries might occur if certain ‘Terminal’ Nerves are damaged.
Injuries to ‘Terminal’ Nerves can lead to conditions such as wrist drop (radial nerve injury) or claw hand (ulnar nerve injury).
Which spinal nerves contribute to the Lumbar Plexus?
The lumbar plexus is formed by the ventral rami of spinal nerves L1 to L4.
Which spinal nerves contribute to the Sacral Plexus?
The sacral plexus is formed by the ventral rami of spinal nerves L4 to S4.
What is the Lumbosacral Trunk?
The lumbosacral trunk is a nerve structure that connects the lumbar plexus to the sacral plexus.
What are the major nerves of the Lumbar Plexus?
The major nerves include the femoral nerve, obturator nerve, and lateral femoral cutaneous nerve.
What are the roles of the major nerves of the Lumbar Plexus?
The femoral nerve innervates the anterior thigh muscles, the obturator nerve innervates the medial thigh muscles, and the lateral femoral cutaneous nerve provides sensation to the skin of the lateral thigh.
What are the possible symptoms of injuring the major nerves in the Lumbar Plexus?
Symptoms may include weakness in leg movement, numbness, and pain in the thigh.
What makes the Sciatic Nerve special in the Sacral Plexus?
The sciatic nerve is the largest nerve in the body and innervates the posterior thigh and all of the leg and foot.
What two nerves make up the Sciatic Nerve?
The sciatic nerve is composed of the tibial nerve and the common fibular nerve.
What are the major nerves of the Sacral Plexus?
The major nerves include the sciatic nerve, pudendal nerve, and superior and inferior gluteal nerves.
What are the roles of the major nerves of the Sacral Plexus?
The sciatic nerve innervates the posterior thigh and lower leg, the pudendal nerve innervates the perineum, and the gluteal nerves innervate the gluteal muscles.
What are the possible symptoms of injuring the major nerves in the Sacral Plexus?
Symptoms may include pain, weakness, and loss of sensation in the lower limb and pelvic region.
Where do cell-bodies of motor-neurons in the Parasympathetic Division come from?
The cell-bodies of motor-neurons in the Parasympathetic Division come from the brainstem and sacral spinal cord.
Where do ganglia of motor-neurons in the Parasympathetic Division typically reside?
Ganglia of motor-neurons in the Parasympathetic Division typically reside near or within the target organs.
How long are preganglionic and postganglionic neurons in the Parasympathetic Division?
Preganglionic neurons are long, and postganglionic neurons are short.
Approximately how much of the Parasympathetic Division does CNX supply?
CNX (Vagus Nerve) supplies approximately 75% of the Parasympathetic Division.
Where do cell-bodies of motor-neurons in the Sympathetic Division come from?
The cell-bodies of motor-neurons in the Sympathetic Division come from the thoracic and lumbar regions of the spinal cord.
Where do ganglia of motor-neurons in the Sympathetic Division typically reside?
Ganglia of motor-neurons in the Sympathetic Division typically reside close to the spinal cord.
How long are preganglionic and postganglionic neurons in the Sympathetic Division?
Preganglionic neurons are short, and postganglionic neurons are long.
Which ANS Division has cell bodies in the lateral gray horn of the Spinal Cord?
The Sympathetic Division has cell bodies in the lateral gray horn of the Spinal Cord.
What are Sympathetic Trunk/Chain Ganglia? Where are they located?
Sympathetic Trunk/Chain Ganglia are a series of ganglia located alongside the vertebral column.
Identify the White Ramus Communicants. What is it?
White Ramus Communicants are myelinated fibers that carry preganglionic sympathetic fibers from the spinal nerve to the ganglia.
Identify the Gray Ramus Communicants. What is it?
Gray Ramus Communicants are unmyelinated fibers that carry postganglionic sympathetic fibers from the ganglia back to the spinal nerve.
What is the general primary path that Somatic motor-neurons take to their targets?
Somatic motor-neurons take a direct path from the spinal cord to skeletal muscles.
Know the three primary paths that Sympathetic motor-neurons take to their targets.
The three primary paths are: synapse at the same level, ascend or descend in the sympathetic trunk, or pass through to collateral ganglia.
What is the advantage to have some motor-neurons go up/down in Sympathetic Trunk?
The advantage is to allow sympathetic innervation to various levels of the body.
What is a Collateral Ganglion? What is a Splanchnic Nerve?
A Collateral Ganglion is a ganglion located anterior to the vertebral column; a Splanchnic Nerve is a nerve that innervates the abdominal and pelvic organs.
What are some less common paths that Sympathetic motor-neurons can take to targets?
Less common paths include traveling via splanchnic nerves to collateral ganglia.
What are Chromaffin Cells? Where are they located?
Chromaffin Cells are modified postganglionic sympathetic neurons located in the adrenal medulla.
What do Chromaffin Cells secrete?
Chromaffin Cells secrete catecholamines, such as epinephrine and norepinephrine.
What is the Pituitary Gland?
The Pituitary Gland is a small endocrine gland located at the base of the brain.
What cells makeup the Anterior Pituitary and the Posterior Pituitary?
The Anterior Pituitary is made up of endocrine cells, while the Posterior Pituitary consists of nerve endings from the hypothalamus.
Be able to distinguish the two cell types (and halves) of the Pituitary in an image.
The Anterior Pituitary contains glandular cells, and the Posterior Pituitary contains neural tissue.
What mechanism activates the Anterior Pituitary? The Posterior Pituitary?
The Anterior Pituitary is activated by releasing hormones from the hypothalamus, while the Posterior Pituitary is activated by nerve impulses from the hypothalamus.
What hormones are secreted by the Posterior Pituitary? Where do they come from?
The Posterior Pituitary secretes Oxytocin and Antidiuretic Hormone (ADH), which are produced in the hypothalamus.
Briefly, what are the functions of hormones from the Posterior Pituitary?
Oxytocin is involved in childbirth and lactation, while ADH regulates water balance in the body.
What hormones are secreted by the Anterior Pituitary? Where do they come from?
The Anterior Pituitary secretes hormones like Growth Hormone, Prolactin, and Adrenocorticotropic Hormone (ACTH), which are produced by its own endocrine cells.
Briefly, what are the functions of hormones from the Anterior Pituitary?
Growth Hormone stimulates growth, Prolactin stimulates milk production, and ACTH stimulates cortisol release from the adrenal glands.
What is the Portal Capillary System in the Infundibulum?
The Portal Capillary System is a network of blood vessels that connects the hypothalamus to the Anterior Pituitary, allowing hormones to be transported directly.
Is Oxytocin Tropic or Non-Tropic?
Oxytocin is Non-Tropic.
Where in the body is the Thyroid Gland located? How large is it, relative to other glands?
The Thyroid Gland is located in the neck, below the Adam’s apple. It is relatively small compared to other glands.
What function does Thyroid Hormone (TH) have? What does TH target?
Thyroid Hormone (TH) regulates metabolism and targets various tissues in the body.
What stimulates the production of TH (T3 & T4)?
Thyroid Hormone (T3 & T4) production is stimulated by TSH from the Anterior Pituitary.
What stimulates the production of TSH?
TSH production is stimulated by TRH from the Hypothalamus.
What is the importance of Iodine, with regard to the Thyroid?
Iodine is essential for the synthesis of Thyroid Hormones (T3 & T4).
What is Colloid made of?
Colloid is made of thyroglobulin, a protein that stores thyroid hormones.
What function does Calcitonin have? What does Calcitonin target?
Calcitonin helps regulate calcium levels in the blood and targets bone tissue.
Where in the body are the Parathyroid Glands located?
The Parathyroid Glands are located behind the thyroid gland.
What is the function of the Parathyroid Gland?
The function of the Parathyroid Gland is to regulate calcium levels in the blood.
What is the function of Parathyroid Hormone? What is its target?
Parathyroid Hormone increases blood calcium levels by targeting bones, kidneys, and the intestines.
What does Parathyroid Hormone antagonize?
Parathyroid Hormone antagonizes calcitonin.
How are Parathyroid Glands stimulated to release hormone?
Parathyroid Glands are stimulated to release hormone in response to low blood calcium levels.
Where in the body is the Pancreas located?
The Pancreas is located behind the stomach.
Does the Pancreas have exocrine functions?
Yes, the Pancreas has exocrine functions.
What are Islets of Langherans (i.e. Pancreatic Islets)?
Islets of Langherans are clusters of cells in the Pancreas that produce hormones.
What are alpha-cells, and what hormone do they secrete?
Alpha-cells are a type of cell in the Islets of Langherans that secrete glucagon.
What are beta-cells, and what hormone do they secrete?
Beta-cells are a type of cell in the Islets of Langherans that secrete insulin.
What are delta-cells, and what do they secrete?
Delta-cells are a type of cell in the Islets of Langherans that secrete somatostatin.
What are acinar cells, and what do they secrete?
Acinar cells are cells in the Pancreas that secrete digestive enzymes.
How is the Pancreas stimulated?
The Pancreas is stimulated by the presence of food in the digestive tract.
Be able to identify the following on a slide: Islet of Langherans (Pancreatic Islets)
Islet of Langherans can be identified as clusters of cells within the Pancreas.
Be able to identify the following on a slide: Alpha Cells
Alpha Cells can be identified as the outer cells in the Islets of Langherans.
Be able to identify the following on a slide: Beta Cells
Beta Cells can be identified as the inner cells in the Islets of Langherans.
Be able to identify the following on a slide: Acinar Cells
Acinar Cells can be identified as clusters surrounding ducts in the Pancreas.
Where are the Adrenal Glands located? How many parts of the Adrenal Gland are there?
The Adrenal Glands are located on top of each kidney and consist of two parts: the cortex and the medulla.
Where is the Adrenal Medulla? What cells makeup the Adrenal Medulla?
The Adrenal Medulla is the inner part of the Adrenal Gland and is made up of chromaffin cells.
What hormones are from the Adrenal Medulla? Are they water-soluble or lipid-soluble?
The hormones from the Adrenal Medulla are epinephrine and norepinephrine, which are water-soluble.
What stimulates the Adrenal Medulla, and in what stress response?
The Adrenal Medulla is stimulated by the sympathetic nervous system during the fight-or-flight response.
What are Chromaffin Cells? Where are they located?
Chromaffin Cells are cells in the Adrenal Medulla that secrete catecholamines.
Where is the Adrenal Cortex? What cells makeup the Adrenal Cortex?
The Adrenal Cortex is the outer part of the Adrenal Gland and is made up of cortical cells.
What hormones are from the Adrenal Cortex? Are they water-soluble or lipid-soluble?
The hormones from the Adrenal Cortex include cortisol and aldosterone, which are lipid-soluble.
What are the layers of the Adrenal Cortex?
The layers of the Adrenal Cortex are Zona Glomerulosa, Zona Fasciculata, and Zona Reticularis.
Which layers secrete which hormones in the Adrenal Cortex? What are their function?
Zona Glomerulosa secretes aldosterone (regulates sodium), Zona Fasciculata secretes cortisol (regulates metabolism), and Zona Reticularis secretes androgens (influence sex characteristics).
What stimulates the Adrenal Cortex, and in what stress response?
The Adrenal Cortex is stimulated by ACTH from the pituitary gland during stress responses.
What is the physiological role of Cortisol?
Cortisol helps regulate metabolism, immune response, and stress response.
Be able to identify the following on a slide: Chromaffin Cells
Chromaffin Cells can be identified as large, dark-staining cells in the Adrenal Medulla.
Be able to identify the following on a slide: Preganglionic Cells
Preganglionic Cells can be identified as smaller cells located in the sympathetic nervous system.
Be able to identify the following on a slide: Adrenal Medulla Layer
The Adrenal Medulla Layer can be identified as the inner layer of the Adrenal Gland.
Be able to identify the following on a slide: Adrenal Cortex Layer: Zona Glomerosa
Zona Glomerosa can be identified as the outermost layer of the Adrenal Cortex.
Be able to identify the following on a slide: Adrenal Cortex Layer: Zona Fasiculata
Zona Fasciculata can be identified as the middle layer of the Adrenal Cortex.
Be able to identify the following on a slide: Adrenal Cortex Layer: Zona Reticularis
Zona Reticularis can be identified as the innermost layer of the Adrenal Cortex.
Be able to identify the following on a slide: Perineal (Fibrous) Capsule
The Perineal Capsule can be identified as the outer fibrous covering of the Adrenal Gland.
Where is the Pineal Gland located?
The Pineal Gland is located in the brain, near the center.
What is the function of the Pineal Gland? What hormone does it secrete?
The Pineal Gland regulates sleep-wake cycles and secretes melatonin.
What is Pineal Sand (i.e. Corpora Arenacea)? Is it dangerous?
Pineal Sand is a calcified structure in the Pineal Gland and is not dangerous.
Where is the Thymus located?
The Thymus is located in the upper chest, behind the sternum.
What is the function of the Thymus? What circulatory system does it utilize?
The Thymus functions in the development of T-lymphocytes (T-cells) and utilizes the lymphatic system.
What hormones does the Thymus secrete? What is their function?
The Thymus secretes thymosin, which stimulates the development of T-cells.
What happens to the Thymus as we age?
As we age, the Thymus gradually shrinks and becomes less active.
Where are immature Lymphocytes (White Blood Cells) formed?
Immature Lymphocytes are formed in the bone marrow.
Where are mature Lymphocytes (White Blood Cells) stored, once developed?
Mature Lymphocytes are stored in the lymph nodes and spleen.
What should you be able to identify on a slide related to the Thymus?
You should be able to identify the Thymus Lobe, Follicle, Cortex, and Medulla.
What hormones are produced by the Ovaries?
The Ovaries produce estrogen and progesterone.
Briefly, what are the functions of hormones produced by the Ovaries?
Estrogen regulates the menstrual cycle and promotes secondary sexual characteristics, while progesterone prepares the uterus for pregnancy.
What hormones are produced by the Testes?
The Testes produce testosterone.
Briefly, what are the functions of hormones produced by the Testes?
Testosterone is responsible for the development of male secondary sexual characteristics and sperm production.
What hormones does anterior pituitary gland secrete
ACTH, TSH, GH, FSH, LH, and prolactin
What does ACTH do? anterior pituitary gland
Stimulates the adrenal glands to produce cortisol
What does TSH do? Anterior pituitary gland
Stimulates the thyroid gland to produce thyroid hormones
What does GH do? Anterior pituitary gland
Stimulates and promotes growth and metabolism
What does FSH do? Anterior pituitary gland
And female stimulates eggs development in male stimulate sperm production
What does LH do? Anterior pituitary gland.
And females triggers, ovulation, and progesterone production in males, stimulates testosterone production
What does prolactin do? Anterior pituitary gland
And female stimulates, milk, production after birth
What does oxytocin do? Posterior pituitary gland.
Place a crucial role in childbirth, lactation and social bonding influencing behaviors, like trust, empathy, and romantic attachments
What does ADH do? Posterior pituitary gland
Regulates water and electrolyte balance in the body primarily by increasing water absorption in the kidneys, which leads to more concentrated urine and reduced water loss
What does thyroid gland secrete?
Thyroxine, triiodothyronine, and calcitonin
What does thyroxine (T4) do in thyroid gland?
Hormone that regulates, metabolism, growth, and development
What does triiodothyronine (T3) do in thyroid gland
More active form of T4, that also regulates metabolism growth and development
What does calcitonin do in thyroid gland?
Hormone that helps regulate calcium levels in the blood
What does parathyroid secrete
Secrete parathyroid hormone PTH
What does parathyroid hormone do?(PTH)
Regulator of blood calcium levels, which they do in response to low calcium level levels
What does thymus gland secrete?
Thymulin, thymus humoral factor, thymopoietin, thymosin
What does thymosin do (thymus gland)
Stimulates the development of T cells, which are essential for fighting infections and other diseases
What does thymulin do (thymus g,and)
Involved in the control of T lymphocyte development
Does thyroid secrete, tropic or non-tropic hormone?.
Tropic
Does parathyroid secrete non-tropic or tropic hormones
Non-tropic
