exam 3

good luck vro last exam

what are the 3 types of capillaries + their function

continuous (controlled exchange of cells), fenestrated (rapid exchange of cells), sinusoidal (passage of cells)

what are the 3 types of arteries + their functions

elastic arteries (conduct blood away from heart), muscular arteries (carry blood to specific organs), arterioles (control capillary blood flow)

what are the layers of the blood vessels?

tunica intima, tunica media, tunica externa

function of the lymphocytes and how do they differ?

T cells and B cells both protect against antigens; B cells build antibodies while T cells target infected cells directly

What are the different types of lymphatic vessels + their associated functions?

lymphatic capillaries (begin lymph flow), collecting vessels (transport lymph to lymph nodes), lymph nodes (filter lymph), lymphatic trunks (drain large body regions), lymphatic ducts (return lymph to circulation)

regions of the lymph nodes?

cortex (contains B cells); medulla (contain B cells, T cells, and plasma cells)

what are the functions of the lymphatic system?

fluid balance (lymphatic vessels and ducts), immunity (nodes and spleen), fat absorption (small intestine)

how is lymph returned to the circulatory system?

lymph flows through lymphatic vessels (capillaries, collecting vessels, lymphatic trunks and ducts), propelled by external forces (skeletal/respiratory pump), drains into thoracic or right lymphatic duct, enters the subclavian veins to become venous blood

different types of tonsils and their locations?

palatine (sides of oropharynx), pharyngeal (roof of nasopharynx), lingual (base of tongue)

types of dural septa found in brain and the cerebellum?

falx cerebri (between cerebral hemispheres), tentorium celebrelli (between cerebrum and cerebellum), falx cerebelli (between cerebellum hemispheres), diaphragma sellae (pituitary gland)

what are the lobes of the brain; and their general functions?

frontal lobe (motor control), parietal (sensory processing), temporal (memory), occipital (visual interpretation)

what are the markings of the cerebral hemisphere?

gyri (hills), sulci (grooves)

different layers of meninges and their organization?

dura mater (periosteal and meningeal layer), arachnoid mater, pia mater (adheres to surface of brain + spinal cord)

functions of the cerebral spinal fluid?

mechanical protection, chemical stability (homeostasis), circulation and transport

different parts of the diencephalon and their functions?

thalamus (sensory relay), hypothalamus (homeostasis), epithalamus (melatonin production)

functions of the autonomic nervous system + the divisions

sympathetic (fight or flight), parasympathetic (rest and digest)

functions of the glial cells within the central nervous system (CNS)?

astrocytes (form blood brain barrier), oligodendrocytes (produce myelin sheath), microglia (immune), ependymal (lines ventricles of brain)

function of the glial cells within the peripheral nervous system? (PNS)

Schwann (production of myelin), satellite (support neuron bodies)

how does the hypothalamus communicate w/ the anterior pituitary gland and what structures are involved with that communication?

hypothalamus releases regulatory hormones through the hypophyseal portal system (median eminence - portal veins - anterior pituitary)

how does the hypothalamus communicate w/ the posterior pituitary gland and what structures are involved with that communication?

hypothalamic neurons synthesize hormones and they are transported down to axons of posterior pituitary gland (through hypothalamo - hypophyseal tract)

what kind of neurons do the spinal cord roots contain?

dorsal (sensory afferent); ventral (motor efferent)

what are the components that make up the neuron + the function of those components?

cell body (soma; maintenance of neuron’s metabolism), dendrites (signal receive), axon (transmits action potentials)

what are the special characteristics of the neurons?

excitability, high metabolic rate, polarization

components of the brain stem + their functions?

midbrain (mesencephalon; visual auditory reflexes), pons (relays signals between cerebrum and cerebellum), medulla oblongata (heart rate; blood pressure)

different components of the axondendritic chemical synapse?

presynaptic axon terminal (conducts impulses towards synapse); postsynaptic axon terminal (transmits electrical signal away from synapse)

how is cerebral spinal fluid produced?

produced by the choroid plexus; through plasma filtration and active ion transport

what ventricles do the cerebral spinal fluid flow through?

lateral ventricle, third ventricle, fourth ventricle, subarachnoid space

how does cerebral spinal fluid exit the brain?

enters the subarachnoid space, gets absorbed by the granulations within the superior sagittal sinus, enters the venous blood shortly thereafter

how do you classify receptors via stimuli?

mechanoreceptors (mechanical forces), thermoreceptors (temperature changes), photoreceptors (light), chemoreceptors (chemicals), nocicreceptors (pain/tissue damage)

how do you classify receptors via location?

mechanoreceptor (skin), thermoreceptor (skin), nocicreceptor (skin external damage), photoreceptor (eyes detect light), chemoreceptor (taste buds; olfactory receptors)

what molecules stimulate the basic taste sensations

sweet (sugar; sweeteners), sour (acid ions), salty (sodium), bitter (alkaloids), umami (amino acids primarily from meat)

vascular layer of the eye (components + functions)

choroid (provides nutrients + oxygen to the retina), ciliary muscles (adjust lens shape), iris (light regulation)

how do amino acid based hormones differ from steroid based hormones?

amino is water soluble while steroid is lipid soluble; aminos receptor locations are the cell membrane while steroids is located in the nucleus/cytoplasm

what hormones from the pituitary gland are considered tropic hormones?

TSH (thyroid stimulating), ACTH, FSH (follicle stimulating), LH (luteinizing)

endocrine glands location?

pituitary, thyroid, parathyroid, adrenal and pineal glands

main difference between a negative and positive feed back mechanism?

negative reduces or reverses a stimulus while a positive amplifies it; the goal of negative is to achieve homeostasis while positive aims at rapid completion

capillaries are the body’s smallest vessels, containing of _____ with a sparse basal lamina (basal thin layer)

endothelium

sympathetic vasomotor nerve fibers innervate the tunica media; what two actions stimulate the narrowing of the vessel and the widening of the vessel?

vasoconstriction narrows the vessel; vasodilation widens the vessel

system of tiny blood vessels that are located within larger blood vessels

vasa vasorum

thick wall mainly with large, low resistance lumen; located within all tunicas particularly within the tunica media

elastic arteries

elastic arteries give rise to this particular artery; also called distributing arteries because they deliver blood to body organs

muscular arteries

smallest of the arteries; participate in vasoconstriction which narrows the vessel and vasodilation which widens the vessel

arterioles

spider shaped stem cells that assist with the stabilization of capillary walls, controls permeability, and plays a role in vessel repair

pericytes

flow of blood through bed from arteriole to venule

microcirculation

branch off the arteriole that further branches into 10-20 capillaries that form the capillary bed

metarteriole

capillaries drain into post capillary?

venules

channel that directly connects arteriole w/ venule

vascular shunt

cuff of smooth muscle surrounding each true capillary that branches off metarteriole

pre capillary sphincter

consists of endothelium and a few pericytes; very porous

venules

prevent backflow of blood; most abundant within the veins of limbs

venous valves

flattened veins with extremely thin walls thus being composed of mostly endothelium

venous sinuses

interconnections of blood vessels are known as what?

vascular anastomoses

provides alternate pathways to ensure continuous flow; even if one artery is blocked

arterial anastomoses

shunts in capillaries

arteriovenous anastomoses

high abundance that occluded veins rarely block blood flow

venous anastomoses

blind-ended vessels that weave between tissue cells and blood capillaries; absent from bones teeth and bone marrow

lymphatic capillaries

specialized lymph capillaries present in intestinal mucosa

lacteals

drains into the right upper arm and right side of the head and thorax

right lymphatic duct

this type of duct trains into the rest of the body

thoracic duct

phagocytize foreign substances and help activate T cells

macrophages

capture antigens and deliver them to lymph nodes; also help with the activation of T cells

dendritic cells

areas where T and B cells mature (bone marrow and thymus for example)

primary lymphoid organs

where mature lymphocytes first encounter their antigen and become activated

secondary lymphoid organs

clusters of lymphoid follicles in wall of distal portion of small intestine

Peyer’s patches

contais a large abundance of lymphoid follicles; destroys bacteria preventing them form breaching intestinal wall, jimmy gaffigan got this particular body part removed

appendix

bilobed lymphoid organs that are found within the inferior neck

thymus

information gathered by sensory receptors about internal and external changes

sensory input

processing and interpretation of sensory input

integration

activation of effector organs (muscles/glands) and produces a response

motor output

brain and spinal cord of spinal dorsal body cavity; integration and control center

central nervous system

portion of nervous system outside of the CNS; contains mainly of nerves that extend from the brain to the spinal cord

peripheral nervous system

type of sensory fibers that convey impulses from PNS to CNS

afferent sensory fibers

convey impulses from visceral organs to CNS (type of sensory fiber)

visceral sensory fibers

transmits impulses from CNS to effector organs

motor (efferent) division

conduct impulses from CNS to skeletal muscle; a voluntary nervous system that deals with conscious control of skeletal muscles

somatic nervous system

contain visceral motor of nerve fibers; regulates smooth muscle and cardiac muscle among others. Considered an involuntary nervous system. has two subdivisions known as the sympathetic and parasympathetic

autonomic nervous system

small cells that surround and wrap delicate neurons

neuroglia (glial cells)

excitable cells that transmit electrical signals

neurons

most abundant, versatile, and highly branched of glial cells. Cling to neurons synaptic endings, and capillaries

astrocytes

small ovoid cells with thorny processes that touch and monitor neurons; can transform to phagocytize microorganisms and neuronal debris

microglial cells

line the central cavities of the brain and spinal column

ependymal cells

branched cells; process wrap CNS nerve fibers; forming insulating myelin sheaths in thicker nerve fibers

oligodendrocytes

clusters of neuron cell bodies in CNS and PNS

CNS: nuclei, PNS: ganglia

gaps between adjacent Schwann cells; sites where axon collaterals can emerge

myelin sheath gaps

thin fibers not wrapped in myelin; surrounded by Schwann cells but no coiling

nonmyelinated fibers

three or more processes (1 axon, other dendrites)

multipolar

two processes (one axon and one dendrite)

bipolar

one T-like process (two axons) also known as pseudo _____

unipolar

associated with sensory receptor

peripheral distal process

enters the cns

proximal (central) process

transmits impulses from sensory receptors toward CNS, almost all are unipolar, located within ganglia in PNS

sensory

carry impulses from CNS to effectors, multipolar, most cell bodies located within the CNS

motor

also known as association neurons, lie between the motor and sensory neurons

interneurons

neurons functionally connected by ________, junctions that mediate information transfer

synapses

neuron conducting impulses towards synapse (sends information)

presynaptic neuron

neuron transmitting electrical signal away from synapse (receives information)

postsynaptic neuron

the axon terminal of presynaptic neuron contains ____ that is filled with neurotransmitter

synaptic vesicles

receptor region on post synaptic neuron’s membrane: receives neurotransmitter; usually on dendrite or cell body. these two parts are separated by fluid filled _______

synaptic cleft

what two components make up the CNS?

brain and spinal cord

evolutional development of rostral (anterior) portion of CNS; resulted In increased number of neurons

cephalization