Midterm 2

- another name for ventral body

- consists of thoracic & abdominopelvic cavaties separated by diaphragm

- not all animal have one

- allows organs to move freely and independently of muscle

- acts as protective cushion for internal organs

- acts as fluid filled hydroskeleton (earthworms)

- forms as hollow cavity in mesoderm

- serous membrane is soon filled with organs

- bud from walls & bring membrane with them

- membranes remain as anchor to wall & connections to other organ

- Organs found inside Ventral Cavity

- Serous membrane of the abdomen

- Also contains large sheets of membrane that bind organs to each other & the abdominal wall

- extensions include mesentery, mesocolon, omentum, and ligament

- All tissues and organs develop from 3 primary germ layers

- ectoderm

- mesoderm

- endoderm

- neural tissue & epidermis

- muscle tissue

- connective tissue

- bone

- serous membranes

- kidneys

- spleen

- gonads

- lining of gut

- liver

- pancreas

- lungs

- thyroid

- parathyroid glands

- Zygote

- morula

- blastula

- gastrulation (formation of germ tissue)

- embryonic disc

- neurulation

- coelom formation

- long, solid bar of mesoderm

- supports neural tube

- becomes nucleus pulposus in adult

- some mesoderm in body becomes segmented

- bone & muscle formation in trunk

- hollow cavity forms in mesoderm

- divided into 2 pleural cavities

- mediastinum and pericardial cavity

- mass of tissue, between pleural cavities

- extends from vertebral column to sternum

- includes all contents of throracic cavity except lungs

- includes heart in pericardial cavity, thymus, esophagus, many large blood and lymph nodes

- thin, flexible sheet of tissue

- composed of epithelal layer & underlying Connective Tissue layer

- includes: mucous membranes, serous membranes, cutaneuous membrane, and synovial membranes

- line cavities that open to outside

- produce mucous

-found in lining of respiratory system, GI tract, repro tract, and most of urinary system

- line body cavities not open to exterior & covers organs there

- all serous membranes are composed of mesothelium (Simple Squamous) and Areolar Connective Tissue

- Secrete serous fluid

- Parietal layer lines body cavity

- visceral layer covers contained organs

- thin, watery, lubricant

- so organs can move freely

- organs in ventral body cavity (Coelom) but not in peritoneal cavity

- behind part of the parietal peritoneum but not covered with visceral peritoneum

- kidneys, adrenals, aorta, vena cava, bladder, uterus, pancreas, duodenum, part of large intestine, not spleen

- GI tract is initially a linear hollow tube

- tube specializes & elongates & twists- stomach, small & large intestine

- Endoderm organs: liver, pancreas, gall bladder, salivary glands

- mesoderm organs: kidney, adrenal, gonads

- Mesoderm: Lungs, heart & large vessels

- Pleura = Lungs

- Pericardium = Heart

- Peritoneum = abdomen

- binds small intestine to posterior abdominal wall

- artery, vein, lymphatic and nerves

- Binds large intestine to posterior abdominal wall

- seperates stomach & liver from organs below

- includes transverse mesocolon - holds transverse colon to wall

- sigmoid mesocolon - holds transverse colon & coils of small intestine

- rest of large intestine is retroperitoneal

- attaches liver to anterior wall

- arises from serosa of stomach

- suspends stomach from liver

- drapes over transverse colon & coils of small intestine

- connects stomach to transverse colon

- has lots of adipose tissue & lymph nodes

- inner part is called mucosa

- outer part is called serosa

- neck

- narrow opening at top of thoracic cavity

- defined by clavicles, first ribs, and sternum

- filled with esophagus, trachea, blood vessels

- blood vessels serving arms pass over first rib & under clavicle

- thoracic inlet is sealed with muscle & connective tissue

- Thoracic Outlet

- divides ventral cavity into thoracic & abdominopelvic cavities

- has a central tendon, muscle extends from this tendon to its attachment to ribs, vertebrae

- Aorta: actually passes behind the diaphragm up against bodies of vertebrae

- Inferior Vena Cava

- Esophagus: opening in esophageal hiatus

- Vagus Nerve: pass through diaphragm with esophagus

- Phrenic Nerve: innervates diaphragm & passes between muscle fascicles of the diaphragm

- there are openings for urethra, vagina, and anus

- each testes starts development attached to posterior body wall

- descend into scrotum, passing through the canal which is over the inguinal ligament

- each one is moved, carries with it a portion of the peritoneal lining into scrotum

- hernia can occur if canal remains open or muscle is weak = a loop of intestine that protrudes through canal

- anterior surface: femoral artery, nerve, and vein pass under the inguinal ligament and over the superior pubic ramus

- Posterior surface: spinal nerves L4-S3 aka sciatic Nerve, which passes through the greater sciatic notch & muscles of the pelvic floor, and down the posterior side of the thigh

- heart, blood vessels and Blood

- Lymph organs

- Lymph Nodes

- Lymphatic vessels

- Lymph Fluid

- Transport O2, nutrients, waste, hormones to/from cells

- participates in regulation of pH, temperature, osmolarity of interstitial fluid

- protection: clotting protects from blood loss, white blood cells protect from microbial invaders

- transmit force for ultrafiltration in the kidney, erection

- complex connective tissue, consists of fluid & cells

- main propulsive organ

- muscular pump

- forces blood around body

- conduits for blood

- distribute blood to cells

- pressure reservoir

- are organs

- return blood to heart

- volume reservoir

- are organs

- where transfer of materials occurs between blood & tissues

- in organs

- two circuits

- sequence of flow

- parallel distribution

- closed systems

- Pulmonary (Low Pressure and Right Heart)

- Systemic (High Pressure and Left Heart)

- Artery, arteriole, capillary, venule, and vein

- exceptions: hepatic & hypthalamic portal veins; efferent arteriole in kidney

- ensures fresh blood supply to all organs

- blood stays in vessels, gets rejuvenated (adds oxygen, add nutrients, and remove wastes)

- oxygenated is stressed, & blood is termed arterial (red) or venous (blue)

- not good or bad, arterial blood comes from kidney but is full of wastes, venous blood comes from intestine but is loaded with nutrients

- involves flow between heart & lungs only

- right atrium receives deoxygenated blood from body organs

- right ventricle pumps blood to lungs for gas exchange (not for nourishment of lung tissue)

- blood leaves heart through pulmonary semilunar valve and pulmonary artery

- blood returns from lungs to left atrium via pulmonary vein

- pumped out by left ventricle with great force

- blood nourishes all organs including heart & lungs

- blood leaves heart through aortic semilunar and aorta

- unidirectional to organs, delivered by arteries and arterioles

- fluid flow leaving organs is via venules to veins & via lymphatics

- part of systemic flow, an unusual pattern

- artery, arteriole, capillary bed, portal vein, capillary bed, venule, vein

- connected capellary beds are in two different organs, used when materials from first organ need to be seen immediately by second organ; i.e. hepatic portal vein and pituitary portal system

- in kidney, two capillary beds connected by this one vessel

- connects gut (stomach, small & large intestine) pancreas & spleen to liver

- ensures that all nutrients absorbed are seen by liver first

- connects hypothalamus to anterior pituitary

- there are four major ones in body, blood, tissue or interstitial fluid, cytosol, and lymph

- others include: cerebrospinal, synovial, peritoneal, pericardial, pleura - all are filtrates of plasma

- 55% plasma, 45% cells & formed elements

- plasma is confined to closed cardiovascular system

- when fluid leaves name is changed intracellular (Cytosol) and extracellular (tissue or interstitial fluid)

- extracellular

- all cells float in this, is a filtrate of plasma

- Intracellular

- cell fluid

- some tissue fluid is returned to closed cardiovascular system via lymphatic vessels

- every organ has lymphatics except brain & spinal cord

- two pumps, right and left

- two circuits: Pulmonary (Right Heart) and Systematic (Left Heart)

- separates 2 different kinds of blood; oxygenated & deoxygenated

- Ensures one way flow with valves

- double layered bag that encloses and protects the heart

- composed of fibrous pericardium and parietal pericardium

- Dense fibrous Connective Tissue

- connected to diaphragm

- serous pericardium

- loose areolar connective tissue & mesothelium

- lies between two serous membrane layers: parietal and visceral

- filled with fluid which reduces friction, cavity provides a space in which heart can move

- second serous layer

- adheres to heart wall

- made of loose connective tissue & mesothelium

- Epicardium

- Myocardium

- Endocardium

- visceral pericardium

- mesothelium & loose Connective Tissue

- heart muscle and cardiac muscle tissue

- cells joined by intercalated discs w/ gap junctions & desmosomes

- cardiac muscle fibers are mechanically, chemically & electrically connected

- cardiac muscle functions like a single enormous muscle fiber

- called functional syncytium (fused mass of cells)

- loose Connective tissue & endothelium

- Connective tissue associated with heart

- each cardiac cell wrapped in fibro-elastic connective tissue & cross linked to others w/ connective tissue

sheets of concentric layers

- wraps around atria and ventricles

- sheets of concentric layers- wraps around atria and ventricles- spiral design helps direct blood flow through heart

- spiral design helps direct blood flow through heart

- stabilizes positions of muscle fibers & valves

- Supports muscle fibers, blood vessels, nerves in myocardium

- distributes forces of contraction

- helps prevent over expansion of heart

- provides elasticity to return heart to original shape between contractions

- isolates muscle fibers of atria from those of ventricles

- base & apex

- atria, ventricles, and auricles

- coronary & intraventricular sulcus

- major vessels

- Chambers of the heart; atria and ventricles

- valves

- major vessels

- coronary circulation

- pectinate muscles, auricles, fossa ovalis

- prominate muscular ridges in right atrium

- serve to slow entry of blood

- remnant of foramen

- ovale which allowed blood to flow between atria and fetus

- choradae tendonae

- papillary muscles

- trabeculae carnae

- intraventricular septum

- folds of muscle in ventricle wall

- serve to slow entry of blood into ventricle

- tendons that attach papillary muscle to Atrio Ventricular valves

- tricuspid valve

- bicuspid valve (mitral)

- aortic & pulmonary semilunar valve

- one way valves

- superior & inferior vena cava & coronary sinus all deliver blood to right atrium

- pulmonary veins feed left atrium

- blood exits via aorta & pulmonary artery

- coronary arteries, coronary sinus

- Pumps to pulmonary system

- walls are thinner

- lungs are very close

- pulmonary vessels are short, resistence is low

- Normal Pulmonary artery pressure at rest: 8-20 mm Hg

- pumps to systematic circulation

- walls are much thicker 2-4x

- When contracts, diameter decreases & lenght shortens

- very effectice pump

- bulges into right ventricle & improves it's pumping action

- Normal systematic pressure at rest 120 mm Hg/80 mm Hg

- 2 kinds of cardiac muscle fibers: contractile and conducting

- 1% cardiac muscle cells become autorhythmic or self-excitable, conducting cells which act as pacemaker cells setting rhythm for entire heart and form conducting system

- route for conducting impulses throughout heart muscle they ensure that heart chambers contract in a coordinated manner

- parts include: Sinotrial Node, Atrioventricular Node, AV bundle and conduction myofibers

- SA Node

- is pacemaker

- atria contract, then ventricles, ventricles contract from apex

- Internodal pathways

- normally slows conduction of the impulse as it travels from the atria to the ventricles providing a delay between activation and contraction of the ventricles

- Bundle of His

- receives the muscle impulse from the AV node and extends into the interventricular septum before dividing into left and right bundles

-conduct the impulse to conduction fibers called purkinje fibers

- begin within the apex of the heart and extend throughout the walls of the ventricles

- larger than other cardiac muscles

- impulse conduction is extremely rapid, consistent with the large size of the cells, and the impulse spreads immediately througout the ventricular myocardium

- Pacemaker potentials initiate cardiac contraction

- cardiac cycle= one heart beat, which consists of systole and diastole

- heart sounds=valves closing

- autonomic control of heart rate via sympathetic and parasympathetic

- electrocardiogram

- external record of electrical activity of heart

- can detect heart murmurs which are abnormal sounds due to blood regurgitation through faulty valves

- coronary arteries are narrow, blood flow is reduced which leads to heart muscle damage

- leading cause of death in U.S.

- symptoms range from mild angina to heart attack

- symptoms start w' 75% narrowing of a coronary artery

- gross necrosis of myocardial tissue due to interrupted blood supply

- damage will affect both contraction and conduction

- heart attack

- group of disease characterized by thickening of the walls of arterie & loss of elasticity

- drug therapy

- angioplasty

- bypaass grafting

- often compared to pipes but are more dynamic they pulsate, constrict, dilate & even proliferate as demanded by changing needs of body

- include arteries, veins, and capillaries

- carry blood away from heart

- thick walled have relatively small lumen

- carry blood under high pressure

- thick wall enables arteries to withstand pressure from heart

- never have valves

- carry blood to heart

- walls are thinner than arteries, relatively large lumen

- blood under low pressure

- have valves= epithelial lining folds back on itself to form valves, only found in extremities

- Intima

- endothelium: simple squamous cells

- lines all parts of cardiovascular system

- basement membrane

- internal elastic membrane or lamina made of elastic fibers

- well developed and lots of it in artery

- poorly developed or even missing in vein

- smooth muscle w/ some elastic fibers in muscle cells

- dominant part of arterial wall in artery (differs in elastic vs. muscular artery)

- smaller amount of muscle in vein

- adventicia

- outermost layer, external elastic membrane

- fibrous and areolar connective tissue, with lots of collagen and elastic fibers, which forms common sheath around companion arteries and veins

- large, thick walled, close to heart

- have largest lumen and more elastin than any other vessel type

- elastin present in all 3 tunics, but tunica media contains most

- includes aorta & its major branches

- allows vessel to withstand great pressure & contribute to moving blood forward via elastic recoil during diastole

- expands when heart contracts & recoil after, maintaining blood flow during diastole

- distribute blood to specific organs

- have thickest media of all vessels

- mostly muscle, less elastic tissue

- muscle cann constrict or relax

- helps regulate blood flow

- considered small arteries, they deliver blood to capillaries

- have small amount of muscle in walls

- muscle that responds to innervation and vasoactive hormones to regulate blood pressure and blood flow

- blood pressure low in veins

- pressure decreases as blood goes through capillary beds

- not enough pressure to return to heart and overcome gravity

- therefore problems with venous return, especially from lower limbs

- presence of valves in veins prevents backflow

- veins can take advantage of arterial flow, as artery expands it squeezes companion vein (Milks it)

- Veins run through skeletal muscle, as muscle contracts it compresses vein & pushes blood towards heart

- breathing, inspiration, creates negative pressure in thoracic cavity, which helps to suck blood up to heart

- considered small veins

- bring blood from capillaries to veins, merge to form veins

- connect arterioles & venules

- not organs themselves, but are parts of the organs they sit inside

- found 2-3 cells away from every cell in body except cartilage and cornea

- vast number= increase of surface are

- have only endothelial cells and small amount of connective tissue

- site of exchange: only place vessel walls are thing enough for this

- grow & regress: depending on need

- Regulatory Devices: have pre-capillary sphincters=rings of smooth muscle

- respond to sympathetic nerves, hormones, local chemicals

- constrict or dilate opening into capillaries and thereby control perfusion of capillary bed

- capillaries do not function independently, ie beds

- have metarteriole followed by throughfare channel, with attached tru capillaries

- if pre-capillary sphincters are clodes, blood goes through metarteriole shunt

- not possible to have all capillary beds open at once

- amount of blood flowing into capillary bed is regulated by nerves, hormones, local chemicals

- continuous

- fenestrated

- sinusoidal

- most common type

- endothelial cells are joined by tight junctions, basement membrane is continuous

- intercellular clefts between endothelial cells

- exchage is limited to small molecules which must pass across capillary wall

- found in skeletal & smooth muscle, lungs and skin

- unique variant in brain and testes, Blood brain/testes barrier

- have pore called fenestrations in endothelial cell membrane

- allow large amount of fluid movement across capillary wall

- useful for filtration & absorption

- found in small intestine, kidney, endocrine organs

- larger in diameter; blood moves through more slowly

- have large fenestrations and clefts & discontinuous basement membrane

- structure allows the passage of large molecules such as proteins and blood cells

- Found in liver, spleen, red bone marrow

- vessels that connect two or more arteries supplying the same body region

- occur between vens and between arteries and veins as well

- provide alternate routes for blood to reach organs

- arteries that do not anastomose

- if blocked, blood supply to whol segment of organ is interrupted produces necrosis of that part of organ

- arteries and veins need to be nourished by capillaries

- walls are too thick for diffusion supply from lumen

- large arteries, tunica interna is nourished by diffusion

- pressure is too great there for capillaries- they would be flattened

- veins must be completely nourished by capillaries because they carry venous blood

- vessels that supply blood to vessel walls

- 60% systematic veins & venules=blood reservoir (especially liver,spleen, skin)

- 15% systemic arteries & arterioles

- 5% in systemic capillaries

- fluid that circulates in the cardiovascular system

- fluid connective tissue: cells + groud substance = Plasma + Fiber (Fibrin)

- study of blood

- clicicians examine this tissue more often than any other to determine cause of disease

- transportation: oxygen, nutrients, wastes, hormones, heat

- regulation: pH, temperatures

- Protection: prevents blood loss by clotting mechanism

- Prevents/limits infection via actions of white blood cells & 2 plasma proteins:antibodies,complement

- Plasma

- Cells

- liquid portion of blood

- consists of water with dissolved solute; electrolytes, nutrients, gases, wastes, regulatory substances, vitamins, and eplasma proteins

- Albumins: exert osmotic pressure, transport steroid hormones

- Globulins: transport fats, iron; one category are the immunoglbulins (antibodies)

- Fibrinogen: important in blood clotting, becomes fibrin

- also called formed elements because not everything is a cell

- basic groups include, red blood cells, white blood cells, platelets

- whole blood is centrifuged

- the % packed RBCs, the liquid plasma

- plasma minus the clotting factors

- if whole blood is allowed to clot

- process is called hemopoiesis

- after birth, occurs in red bone marrow

- proximal epiphyses of humerus & femur, sternum, ribs, cranial bones, vertebrae, pelvis

- all blood derives from single kind of stem cell

- Proerythroblasts: erythrocytes

- myeloblasts: granulocytes: neutrophils, basophils, eosinophils

- monoblasts: monocytes

- Lymphoblasts: lymphocytes- B & T cells

- megakaryoblasts: platelets

- red blood cells

- small cells used as reference to help ID other cells

- biconcave disc: more surface area & flexible shape allows squeezing through capillaries

- red because of hemoglobin

- membranes contain proteins that determine blood type (A,B,O, AB, Rh +,-)

- oxygen carrying pigment bound to protein

- carry gases

- Oxygen (Iron atom held by heme

- CO2 (Protein, globin)

- live 120 days

- have no organelles, cant do repairs, lots of wear & tear on membrane squeezing thru caps

- worn out cells removed & destroyed by fixed macrophages in spleen & liver

- erythropoiesis, stimulated by erythropoietin, a hormone made by kidneys

- hemotocrit= % RBCs in blood, normal is 38-46% females, 40-54% males

- formed from megakaryocytes in red bone marrow

- cell fragments, no nucleus, but stain dark due to granules

- help plug small holes in damaged blood vessels

- granules contain chemicals that upon release help to form clots

- removed by phagocytes in spleen, liver

- Whiteblood cells

- well defined nucleus & organelles

- ameboid, usually leave blood & travel to site of infection

- can live for years, especially memory lymphocytes, some days, and during infections only few hours

- Granular which includes eosinophils, basophils, and neutrophils

- agranular which includes monocytes and lymphocytes

- cytoplasm has granules that stain differentially

- nuclei are lobed

- affinity for acidic stains, stain red, have distinct bilobed nucleus

- fairly rare 3-5%

- leave capillaries & enter tissue fluid

- release histaminase to counter effects of histamine

- phagocytize antigen-antibody complexes

- effective against certain parasitic worms

- high count indicates allergic condition or parasitic infection

- affinity for basic stains- granules stain dark blue

- granules contain histamine & heparin; like mast cells which are fixed in CT

- nucleus is S shaped, often obscured by blue granules

- migrate sites of injury, involved in inflammatory & allergic reactions

- granules are lysosomes, contain 20 different kinds of enzymes

- multilobed nucleus, sometimes called polymorphonuclear leukocytes

- most common type

- phagocytic, arrive first on the scene of an infection

- chemicals released from microbes & from inflamed tissue attract them=chemotaxis

- arrive from blood by diapedesis

movement through capillary walls

- cytoplasm stains uniformly

- no granules

- ameboid

- large cells, have kidney shaped nucleus & ligth pale blue cytoplasm

- phagocytes differentiate into macrophages

- take longer to reach site of infection than neutrophils, arrive in large numbers, destroy more microbes

- macrophages are the cells that activate B & T lymphocytes

- have very large nucleus, adheres to one side of cell membrane, cytoplasm stains sky blue

- most are lymph nodes

- two kinds of lymphocytes: B & T cells

- killer cells

- shoot virally infected & cancerous cells with protein bullets (Perforin)

- introduction to antigen

- differentiate into plasma cells whic make antibodies

- antibodies facilitate destruction of bacteria by several mechanisms

- Special cells: Lymphocytes & macrophages

- Fluid: Lymph

- Lymphatic Vessel: Carry lymph (Lymphatics)

- Lymphatic Tissue: loose Connective Tissue; framework of reticular fibers, with cells hanging in framework

- Lymphatic Organs: Bone marrow, thymus, spleen, lymph nodes

- Lymphatic Nodules: tonsils, lymphatic nodules

- Mucosal associated lymphatic tissue

- two functions

- Circulatory and immune

- performed by vessels

- drains interstitial fluid which serves as an aid to venous return of fluid

- also transports dietary fats

- performed by cells, tissues, organs

- system provides protection from pathogens

- cells (Macrophages, B & T lymphocytes) eat and shoot pathogens

- tissues & some organs provide the sites for immune function

- marrow & thymus are where immune cells are born & educated

- virtually identical to tissue fluid, no event changes it

- some proteins do leak from capillaries & are returned to blood via lymph

- fact that proteins fit in means that bacteria & viruses can also

- similar to veins but thinner

- same tunics, have more valves, follow similar drainage courses

- artery, vein, lymphatic & nerve usually run together

- vessels include; capilaries => lymphatic vessels => lymphatic ducts => subclavian veins

- unique

- blind-ended & overlapping endothelial cells, the overlap permits fluid to flow in when pressure is higher outside but not back out, these capillaries have very high permeability

- specialized liymphatic capillary on villi of small intestine

- transport of fat from intestine to blood

- mainatined by skeletal muscle contraction

- helped by valves & respiration

- every organ has lymphatis exept avascular tissue, CNS, splenic pulp, and bone marrow

- 2 major lymphatic vessels dump lymph back into venous flow just before it enter the heart

- thoracic duct and right lymphatic duct

- begins as dilation called cisterna chyli at L2

- runs from there to junction of internal jugular and left subclavian veins

- main collecting duct of lymphatic system

- collects from left side of head, neck, chest, left arm & entire body inferior to diaphragm

- drains lymph from legs and chyle from intestine

- drains from upper right side of body

- lymph enters blood at juncture of internal jugular vein and subclavian vein

- flows directly into brachiocephalic vein

- reticular tisse, loose, reticular fibers are laid down by fibroblasts

- form a network that holds lymphocytes & macrophages

- can also be found in liver

- most infection occur

- most infectious organisms are destroyed

- most circulating lymphocytes gather

- most antigen challenges occur

- most effector & memory lymphcytes are produced

- Lymphoid organs: thymus, spleen, nodes

- Lymphoid tissues: localized patches in MALT, GALT, Peyer's patches, tonsils

- Red bone marrow & thymus gland

- site of production & education of lymphocytes B&T cells

- lymph nodes and spleen

- site of immune function

- attack vs pathogens

- outer capsule

- trabeculae

- stroma

- parenchyma

- cortex

- medulla

- hilus

- Dense Connective Tissue

- outer capsule extends into organs as struts

- framework

- functional part

- outer part

- inner part

- depression on surface where vessels enter, leave organ

- Lymphatic vessels run through these

- oval or bean shaped structures located along lenght of vessels

- located in armpit, groin, neck, behind knee, breasts, omentum, mesentary

- most spreading of cancer occurs through lymphatic system

- Stroma

- perenchyma

- framework which is made of capsule, trabeculae, reticular fibers and fibroblasts

- 2 parts, cortex and medulla

- follicles: regions of densely packed lymphocytes, B cells & macrophages in outer part, and t cells are deeper

- Germinal Center: where B cells => plasma cells

- medulla: b lymphocytes & plasma cells are packed into cords

- only organs that filter lymph

- flow is one way, directed by valves, from afferent vessels, through sinuses, out efferent vessels

- foreign material trapped by reticular fibers, destroyed by mactophages & lymphocytes

- efferent lymphatics & blood vessels enter/leave at hilus

- largest mass of lymphatic tissue in body, built like lymph node

- found on left side of body, has indentations for stomach, kidney, part of large intestine

- covered w/ dense Connective Tissue capsule, that is covered w visceral peritoneum

- has no afferent lymphatic vessels, does not filter lymph

- filters blood much like a node filters lymph

- served by splenic artery of celiac trunk

- drains into hepatic portal vein

- lymphatic tissue

- arranged around central arteries

- performs immune function

- cords of splenic tissue

- arranged around blood sinusoids

- blooed enters pulp and is checked for dead RBCs by cells in splenic cord

- blood then exits spleen via splenic venules

- main function is phagocytosis of RBCs & bacteria

- RBC particles are bound to protein, sent to liver to make bile

- serves as site for B cell proliferation into plasma cells

- major source of antibodies in body

- serves as reservoir for blood

- lymph nodes can take over if spleen removed

- Mucosa associated lymphoid tissue

- form ring at junction of oral cavity & pharynx

- positioned for immune surveillance

- fight pathogens that are inhaled or ingested

- perform immune surveillance on mucus from mouth and nasal cavity unlike nodes

- bilobed gland located in mediastinum, poterior to sternum, medial to lungs

- covered w/ CT capsule

- regresses after puberty, fat & CT replace thymus tissue

- check for & remove pathogens, cancerous cells

- Lymphocytes are part of specific immune response

- lymp organs & tissues are site of WBC production & attacks

- areolar CT is also site of immune function, especially as found in dermis & mucous membranes

- 3 major crisis: infection or invasion, Injury, and cancer

- 2 major responses: inflammation & specific Immune response

- occurs in response to injury or infection

- initiated by mast cells that release histamine & heparine

- purpose is to bring blood warriors, elevate temperature, seal off area, pain offers protection

- Causes leaky capillaries

- reddening, swelling, hot, and pain

- anticoagulant

- acts on tissue fluid, allows cells to move freely through

- phagocytize and invaders

- present antigen

- clean up debris like dead cells

- bind & engulf foreign invaders & antibodies coated pathogens

produce antibodies

- repair tissue

- scar tissue

- must recognize antigen and be activated by helper t cells

- happens in nodules, nodes, spleen

- B cells become plasma cells, then make antibodies, which act against bacteria & free viruses

- Recognize antigen & be activated by helper T cells

- kill via shooting with perforin

- act against virus infected cells & cancer cells

- information system

- communicates, controls, coordinates and shares function with the endocrine system

- hard-wired

- unique feature is that cells generate electrical impulses & conduct them

- generate an electrical impulse

- non-mitotic after second year of life

- connective tissue cells for NS as there is no CT ther

- cant generate impulses

- cells: neuron & neuroglial cells

- tissue: nervous tissue

- Organs: brain & spinal cord; nerves & ganglia

- System: unified anatomically: all parts are same tissue & physically connected

- anatomical: CNS & PNS; sensory & motor, somatic & autonomis, S & PS

- Functional: information flow, receptor, sensory, integrator, motor and effector

- housed in bone

- brain and spinal cord

- includes all nerves which radiate to and from CNS as well as ganglia

- includes 2 division; Sensory and Motor

- Special & general

- somatosensory & Visceral

- limited to head & face

- vision, hearing, equilibrium, taste, smell

- Body wide receiving ability

- touch, temperature, pressure, proprioception, pain

- sensory input that is conciously perceived from receptors

- sense external environment

- eyes, ears, and skin

- Input that is not consciously perceived from receptors of blood vessels and internal organs

- sense internal environment

- heart etc

- targets skeletal muscle and is voluntary

- skeletal muscle responds

- targets smooth & cardiac muscle, glands, involuntary

- fight or flight

- rest and digest

- Sensory receptors

- sensory neuron

- integrator

- motor neuron

- effector

- Special receivers/transducers; can detect temp, press, sound, position, light

- Pass information via nerves, where it is interpreted and assigned value

- purpose: constantly sample external and internal environment in order to respond and maintain homeostasis

- sensory information must be sent to integrator for interpretation

- travels along afferent/sensory neuron

- found in CNS,

- info gathered, sorted, deciphered, integrated & judgements are made

- response can be "thats fine" or "no", we need to respond, or make an adjustment to maintain homeostasis

- information is sent from integrator to effector via efferent or motor neuron

- are muscle or gland

- organs make changes in conditions being monitored

- can conduct electrochemical impulses & can store information

- functional cells of the NS

- can add fine branches & connections but cannot divide after 2 year of life

- processes of fibers(axons and dendrites) can regenerate if neurilemma remains in PNS only

- contains nucleus, cytoplasm, nissl bodies, neurofibrils and axon hillocks

radiate out of dendrites into cell body & into axon

- cytoskeletal structure

- carry neurotransmitters from cell body to end of axon=transaxonal transport

- impulse initiation area, contains no nissl bodies

- cell processes/extensions

- dendrites transmit info to cell body, can range from 1 to several thousand per cell

- axon transmit info away from cell body, always one per cell body, releases neurotransmitters

- long axon

- space between 2 neurons, site of neurotransmiiter release

- 3 parts: axon terminal, synaptic cleft, post-synaptic membrane

- multipolar

- bipolar

- unipolar

- largest, most common

- all motor neurons are multipolar

- any neuron whose cell body is in central nervous system is multipolar

- also ganglia of autonomis nervous system

- one process that branches to form dendrites & one other process, an axon

- confined to special senses

- bipolar but cell body is off to one side

- associated only with general sensory fibers,

- only in dorsal root ganglia

- transmit info on touch, pressure, pain, temperature, position

- sensory neurons

- motor neurons

- interneurons

- transmit info towards CNS; have peripheral & central process

- transmit info away from central nervous system

- all multipolar

- association neurons

- confined to central nervous system

- nerve impulses

- polarized, can change polarity over time & conduct change down lenght of process

- axons conduct action potentials or nerve impulses

- dendrites & cell bodies conduct gragded potentials

- synapses relase & receive neurotransmitters

- supporting cells

- provide metabolic support, electrical insulation

- highly mitotic

- prevent electrical interference

- astrocytes

- oligodendrocytes

- microglia

- ependymal

- star shaped

- have perivascular feet that atttach to neurons & blood vessels

- help control ionic environment

- blood brain barrier

- fewere branches than astrocytes

- form myelin sheath around large CNS axons

- one cell wraps part of several axons

- small cells

- macrophages of Central nervous system

- form epithelial lining of ventricles & central canal

- form cerebralspinal fluid in ventricles

- ciliated to move CSF in central canal

- Schwann cells

- satellite cells

- form neurolemma & myelin sheath which insulate large axons

- small diameter axons, schwann cells hold several axons in neurlemma, but no myelin sheath forms

- surround sensory neuron cell bodies within ganglia,

- regulate exchange of nutrients and wastes between neurons and interstitial Fluid

- insulation: accomplished with neurogliagl cells & myelin

- serves to insulate & protect fibers

- increase rate of impulse conduction

- unmyelinated axons, cell bodies and dendrites

- require less wiring

- myelinated fibers running between different parts of CNS

- white matter axons traveling to similar destinations form bundles called tracts

Nerves & ganglia

- bundles of axons

- axons in nerves conduct information between sensory receptors/effectors and the CNS

- van be regenerated if cell body is not destroyed & myelin sheath remains

- cranial and spinal

- originate in brain

- radiate away from brain

- usually short (except Vagus)

- innervate structures of face & head

- originate in spinal cord

- typically long

31 pairs

- 8 cervical, 12 thoracic, 5 lumbar, 5 sacral, 1 coccyx

- epineurium: fibrous CT outside of nerve

- perineurium: covers fascicles

- endoneurium: areolar CT, covers individual fibers

- collection of neuron cell bodies outside the CNS

- two kinds: sensory and autonomic ganglia

- contain sensory neuron cell bodies (unipolar and bipolar)

- contain postganglionic ANS cell bodies & dendrites

- synapse with ANS pre-ganglionic neurons

- wiring diagram of NS

- route followed by series of nerve impulses from origin in dendrites of 1 neuron to arrival elsewhere in body

-collection of nerve fibers in CNS having the same origin, destination, function

- arrangement of interneurons in specific patterns

- serial, diverging, converging, reverberating and parallel

- most simple neuronal circuit, neural pathway

- rapid, automati motor responses to stimuli

- unlearned, involuntary, unpremeditated

- receptor (Sensor), sensory neuron (Afferent), interneuron, motor neuron (Efferent), effector

- sensory receptor: found all over body

- sensory neuron: fiber in nerve, cell body ganglion

- interneuron: in CNS; complexity of response relates to # of interneurons, simple reflex has only 1

- motor neuron: cell body in cord or brain, axon leaves & becomes part of nerve

- Effector: muscle and Glands

- differ from reflex arcs because they have more than one interneuron

- meninges

- dura mater

- arachnoid

- pia mater

- CT coverings that encircle brain & spinal cord

- dense fibrous CT

- collagen & elastic fibers

- delicate CT with collagen

- vascular

- tapers end of spinal cord

- there are cervical & lumbar enlargements

- collection of roots

- anchors spinal chord laterally

- protects from shock & displacement

- extensions of pia mater that fuse with dura

- fuses with terminal filament of dura (filum terminale) coccygeal ligament

- general sense neurons terminate here

- synapse with interneurons

- autonomic motor neuron cell bodies here

- innervate smooth muscle, cardiac muscle, glands

- somatic motor neuron cells bodies here

- innervate skeletal muscle

- contains axons of one ascending sensory tract

- general sensory axons of neurons carry information

- meissner corpuscles, and joint receptors

- contains both sensory and motor tracts

has both sensory & motor tracts

- one for each segment of the cord

- carry general sensory information

- sympathetic trunk ganglia

- collateral ganglia

- PS ganglia

- highway: nerve impulse conduction, contain tracts carrying information to'from brain

- integration center: serves as integrating center for spinal reflexes

- cutaneous area receiving most of its innervation from one spinal nerve

- area of skin that provides sensory input to the posterior roots of one pair of spinal nerves or to one spinal cord segment

- muscle group innervated by one spinal nerve

- note each spinal nerve innervaates one dermatome and one myotome

- network of interweaving anterior rami of spinal nerves

- two roots leave spinal cord: ventral contain motor fibers, and dorsal root contains sensory fibers

- ventral and dorsal roots join & from a mixed nerve

- nerve passes through intervertebral foramen & divides into branches called rami

- serves deep muscle & skin of dorsal surface of trunk

- serves muscles & structures of upper, lower extremities, and lateral & ventral trunk

- hold components of autonomic nervous system

- conducts integration part of information flow

- interpretation of sensory input

- control of motor output

- integration => thought , emotion, memory, intellect

- gray matter is cell bodies= cortex and nuclei

- white matter= myelinated fibers

1. ectoderm origin of NS

2. Neural Tube

3. 3 primary vesicles

4. Overgrowth of Telencephalon

5. Ventricles follow growth

6. gray & white matter

- neural plate, neural groove folds becomes neural tube, made of neuroblasts => neurons & glial cells

- neural crest cells => mass of cells between neural tube & skin ectoderm can migrate. becomes dorsal ganglia, spinal nerves, cranial nerves, ANS ganglia, adrenal medulla

- notochord: supports tube before bone forms, becomes nucleus pulposus

- hollow

- walls form central nervous system and central cavity

- ventricles and central canal

- anterior tube becomes brain

- posterior becomes spinal cord

- Prosencephalon = forebrain

- mesencephalon = midbrain

- rhombencephalon = hindbrain

- telencephalon = cerebral hemispheres & basal nuclei

- diencephalon = thalamus & hypothalamus

- mesencephalon = midbrain

- metencephalon = pons & cerebellum

- myelencephalon = medulla oblongata

- Sprouts 2 swellings that become cerebral hemispheres that are seperated by longitudinal fissure

- grows forward & then back over diencephalon, w/ smell center at tip of horn

- those in telecephalon become lateral ventricles

- diencephalon => 3rd Ventricle

-mesencephalon => cerebral aqueduct

- metencephalon => 4th ventricle

- myelencephalon => 4th ventricle

- inner layer of cells, near ventricles becomes basal nuclei, while other gray matter cells migrate & form cortex

- connections become myelinated => white matter, fiber tracts

- processes grow towards specific targets in branching like pattern

- Telencephalon => cerebrum: hemispheres, cortex, nuclei, lateral ventricles

- diencephalon => thalamus, hypothalamus, third ventricle

- mesencephalon => midbrain; red nucleus, substantia nigra, aqueduct

- metencephalon => pons & cerebellum fourth ventricle

- myelencephalon => medulla oblongata and fourt ventricle

- tracts & nuclei, 4th ventricle

- pyramids: contain motor tracts, from cerebrum to spinal cord

- olives: conduct proprioceptive info to cerebellum, contribute to equilibrium

- regulates, swallow, hiccup, vomit, cough, sneeze

- cranial nerves 9-12

- tracts and nuclei

- connects 2 lobes of cerebellum

- Middle cerevellar peduncles: tracts connect cortex, pons to cerebellum

- superior cerebellar peduncles: tracts connect cerebellum, midbrain, to cortex

- inferior cerebellar peduncles: tracts that bring proprioceptive info from vestibular nuclei & cord longitudinal tracts are motor & sensory tracts

- respiratory control

- Cranial nerves 5-8

- tracts and nuclei

- corpora quadrigemina: Superior colliculi => moves head in response to visual, inferior colliculi => moves head in response to auditory

- nuclei: incluede red nuclei, substantia nigra, peraqueductal gray

- 3-4 cranial nerves

- subcortical somatic motor center

- part of reticular formation, iron pigment

- functionally linked to basal nuclei axons project to globus pallidus

- has inhibitory effect

- addiction

- surrounds aqueduct, involved in fight/flight

- reticular formation

- brings us on line each morning, off line at night

- relay station for all sensory information except smell

- Relays info, processes, organizes and amplifies information

- 12 nuclei

- 12 nuclei

- ANS control of effectors

- emotions/behaviors

- homeostasis

- pituatary gland

- only output neurons of cerebellar cortex

- ensures smooth coordinated body movements

- compare motor plan from cortex with sensory input on current movements, equilibrium, and makes adjustments by sending info back to cortex

- adjusts posture to maintain equilibrium

- motor: primary motor cortex, broca's area

- sensory: Primary somatosensory cortex

- association: prefrontal cortex, language areas, insula

- Controls precise skilled voluntary movements

- precentral gyrus: primary motor cortex

- pyramidal cells here project in pyramidal tracts to motor neurons

- serves as memory bank

- broca;s area controls speech

- processes somatic sensory input

- touch pressure pain and temp

- postcentral gyrus: primary somatosensory cortex

- Processes visual input, interprets shape, color and movement