• RBCs-erythrocytes
• WBCs-leukocytes
• Platelets-thrombocytes

(all are suspended in ECM called plasma)

1. delivery of nutrients and O₂
2. elimination of waste and CO₂
3. regulation of body temp.
4. acid/base and osmotic balance

• it is the yellowish fluid portion of blood
• during coagulation the cells and other components are integrated into clot

• biconcave disks
• shape provides surface area which enhances gas exchange
• flat in the middle due to as RBCs mature the expel the nucleus and some organelles
• stain salmon to pink
• avg. life span is 120 days and then destroyed in the spleen, marrow, and liver

What are leukocytes?

• do not function in blood stream, they travel from different sites in the body to site for specific function
• when they reach destination, they leave blood and enter tissue by migration through endothelial cells of BV

1. Granulocytes-presence of granules
2. Agranulocyes-no granules

1. granulocytes-neutrophils, eosinophils, basophils
2. agranulocytes-lymphocytes, monocytes

• polymorphonuclear leukocytes (PMNs)
• have a multilobed nucleus
• lobes are connected by thin chromatin threads

[image]

• migrate to site of infection
• at the site of infection they are phagocytic and release hydrolytic enzymes
• assist in inflammatory process

• sausage shaped, bi-lobed nucleus
• lobes are connected by a chromatin thread

[image]

• destruction of parasitic worms
• hydrolysis of antigen-antibody complexes(allergic response)

• they have an S-shaped nucleus
• nucleus is masked by large cytoplasmic granules

[image]

• they attract leukocytes to site of infection

anaphalactic shock-comes from a second exposure to antigen

• large # of basophils degranulate which causes vasodialation which then causes circulatory shock
• smooth m. of respiratory sys constricts=respiratory shock

• largest of circulatory cells
• large, kidney shaped nucleus with a bubbley appearance
• stay in circulation for a few days then migrate into the tissue and become macrophages

[image]

• phagocytose dead or defunct cells and antigens
• produce cytokine which activate inflammatory response and stimulate expansion of other immune cells
• also fuse together to form "giant" cells, this makes them large enough to phagocytose very large cells

• they are a little larger than RBCs
• nucleus slightly indented and takes up most of cell

[image]

1. T-cells
2. B-cells
3. NK-cells

• small, disk shaped(slightly irregular)
• non-nuclear fragment from megakaryocytes in bone-marrow
• functions to limit gemorrage to endothelial lining of vessels in injury situations
• they aggregate and participate in blood clotting

• soft, gelatinous, highly vasular
• highly cellular-responsible for blood cell production(hematopoesis)
• 5% of body weight

1. Red-has a greater # of RBCs and is found in newborns
2. Yellow-has a greater amount of adipose and is found mostly in adults

• est. a trillion neurons
• there are receptors on the terminal ends of neurons which transduce signals to higher centers for perception and motor response

CNS(central)-brain and spinal cord

PNS(peripheral)-cranial nerves from brain, spinal nerves from spinal cord, associated ganglia

1. Sensory(afferent)- receives and transmits signal to CNS
2. Motor(efferent)- originates in CNS and transmits to effector organs

1. somatic - neurons to muscles
2. autonomic - neurons to ganglia to cardiac and smooth m. and glands

Abnormal organogenisis of NS results in congenital defects:

1. Spina Bifida - defective closure of spinal column
2. Anencephaly - failure of the anterior neuropore to close(leads to poorly formed brain and absent cranial vault)
3. Epilepsy - abnormal migration of brain cortical cells which disrupts neuron function

1. neurons - receptive, integrated, motor functions, size range 5-150 µm
2. neuroglial cells - support and protect neurons

1. axon
2. cell body(soma)
3. dendrites

[image]

• large, spherical, centrally located
• has well defined nucleus with nucleolus and nissel bodies(contain ER and polyribosomes)
• have neurofibrils-cytoskeleton

• sensory terminals
• branch from cell body
• some have spines on surface which are related to sensory selectivity and control

they diminsh with age and poor nutrition and exibit structural changes=trisomy 13 & 21

13-Patay's syndrome

21-Down's syndrome

• arise from soma at the "hillock"
• single thin process; longer than dendrites
• some are mylinated or unmylinated

• transport molecules back and forth from nucleus of neuron (enzymes, proteins, viruses)

1. myelin sheath-formed by neuroglia(shwann)cells that surround axon which make the impulse faster
2. mylinated=white matter
3. unmylinated=gray matter

There are 4 types based on shape and arrangement of the processes.

1. unipolar
2. bipolar
3. pseudounipolar
4. multipolar

• provide mechanical/metabolic support/protection for neurons
• do not propigate or react to nerve impulses

1. astrocytes
2. oligodendrocytes
3. microglial
4. ependymal cells

• interfaces b/w myelin sheaths of 2 schwann cells
• exist along axons

[image]

CC of myelin

Multiple Sclerosis

• affects myelin - 1.5x more common in females
• demylination occurs which causes random episodes of inflammation and edema which can go into remission for months/yrs
• each episode jeopardizes vitality
• autoimmune disease
• treat with corticosteroids

• bundles of axons surrounded by vestments

1. bundles are called fascicles
2. vestments are the epi-, peri-, and endoneurium

What is the CNS?

• brain + spinal cord

• Has gray/white matter

Gray matter

• has unmyelinated axons, aggregations of neurons, neurogial cells
  
• Located in cortex of cerebellum and cerebrum

• is mostly mylinated nerve fibers
• White matter lies deep to cortex
• The reverse is  true in spinal cord- white matter is at periphery

What are the CT coverings of the Brain?

• Collectively called the meninges

1. Dura mater
2. Arachnoid mater
3. Pia mater

[image]

dense CT (outer)

2. Arachnoid mater

3. Pia mater

What is the Choroid Plexus?

• folds of pia mater, abundant capillaries, and extend into brain ventricles
  
• Produces cerebrospinal fluid (CSF)

What is the cerebral cortex?

•  gray matter folded in the gyri and sulci
•  Learning, memory, info analysis, motor response, integration of sensory signals
• has 6 layers
  

What is the Cerebellar cortex and how many layers does it have?

• gray matter at the periphery of the cerebellum
• responsible for balance/equilibrium, muscle tone, coordination of skeletal muscle

• Has 3 layers

1. Molecular layer
2. Purkinje layer
3. Granule layer

The Circulatory system- 2 separate but related systems

1. cardiovascular- two way (to/from the heart), carries blood between heart and tissue

2.lymphatic vascular- one way (to heart), collects lymph and deposits it in the cardiovascular system

lymph- extracellular tissue fluid

What are 4 types of Circuits?

1. Pulmonary circuit- to lungs
2. Systemic circuit- to body
3. Arteries/capillaries- away from heart
4. Veins- to heart

What are some defining features of blood vessels?

• varies by location
• diameter varies by location
• arteries' walls thicker than veins
• arteries look round, but veins look mis-shapen
• lymph vessels resemble veins

What are the 3 Blood Vessel layers?

They are called tunics.

1. Tunica intima- inner (endothelium)
2. Tunica media- middle (smooth muscle)
3. Tunica adventitia- outer (elastic CT)

a)Tunica adventitia = serosa (refers to the outer covering  in organs) NOT INTERCHANGABLE

-small arteries that enter large vessels to nourish media and adventitia

[image]

Arteries- Classification:

Elastic-largest

•   Branches from the aortic arch

• Endothelial cells contain inclusions- Weibel Palade bodies

• Bodies contain von Willebrand's factor which facilitate coagulation of platelets

Clinical Correlation of arteries

von Willebrand's disease- inherited, prolonged clotting time, excessive bleeding at injury

[image]

1. Tunica media

- fenestrated (has pores), fibers of elastin, interspersed smooth muscle

2. Tunica adventitia

- vast vasa vasorum

- most of the "named" arteries. Eg: brachial, ulnar, renal; thick t. media with much smooth m.

• arteries with diameter of less than 0.1 mm
• histologically lumen size=width

1. arteriosclerosis - thickening of artery walls, loss of elasticity and Ca deposition
2. atherosclerosis - infiltration of lipid "plagues" into the t. intima; most common in large arteries

• reduces lumen size, makes it prone to obstruction=heart attack

(capillaries are at the ends of arterioles)

1. fenestrated
2. continuous
3. sinusoidal

• has pores
• find in pancreas, intestine, endocrine glands

• no interruptions in walls(no pores)
• in muscle, NS, CT

• channels that conform to shape of where they lie
• in bone marrow, liver, spleen, other lymphoid organs, some exocrine glands

[image]

• single layer of endothelial cells, small lumen
• have pericytes along outside of capillaries (control size)

• they exist at the end of capillaries
• they empty into larger veins
• cap.s in tissues→veins→venules→increasingly larger vessels→heart

• veins out number arteries and are larger
• 70% of blood volume is in veins
• veins parallel arteries
• veins are usually collapsed b/c thinner and lower blood pressure

1. small
2. medium
3. large

(all have same tunics as arterie but are thinner)

• varicose veins - abnormally large veins at the surface next to skin
• mostly seen in elderly
• result from: loss of muscle tone, degeneration of vessel walls, valve incompetence

Heart:

3 Layers of the heart wall

1. endocardium
2. myocardium
3. epicardium

[image]

• lines h. lumen
• endothelial cells
• underneath is small amount of CT and within CT there are small BV and Purkinje fibers

• thickest layer
• spiral cardiac m. cells around the chamber orifices

• specialized cells that conduct impulses for contraction called Bundle of H.I.S.
• cells then travel from BOH and become Purkinje fibers

• has simple squamous epi.
• when it surrounds organs=mesothelium
• has loose CT, fat, nerves
• where vessels enter and leave heart
• vecomes continuous with visceral and parietal pericardium to enclose the pericardial cavity

1. pericarditis - infection of paricardial cavity

• causes adhesions b/w epicardium and cavity
• severely restricts heart beat

2. Ishemic coronary heart disease- atherosclerosis of coronary vessels of myocardium

• blood flow is restricted
• patient may have "refered" pain(pressure from lack of oxygen)=angina

• series of vessels that remove excess tissue fluid(lymph) and returns it to the cardiovasular system
• spans entire body except orbit of eye, CNS, internal ear, epidermis, cartilage, bone
• open system with no pump
• lymphatic capillaries drain tissues then empty into larger lymphatic vessels
• ducts empty into cardiovascular system
• lymph nodes are interspersed along system

• it causes lymph to be moved around so antigens will come in contact with antibodies and immune system

• malignant cells spread via lymph
• when reach lymph nodes they are slowed and can divide
• eventually leave and metastisize in other organs