301 Final pt 2

dwarfism

hypo secretion of hGH

gigantism

hyper secretion of hGH BEFORE epiphyseal plates fuse

acromegaly

excessive hGH AFTER epiphyseal plates fuse

cretinism

hypothyroidism

myxedema

hypothyroidism

grave’s disease

hyperthyroidism

exophthalmos

hyperthyroidism

addison’s disease

hyposecretory disorder of adrenal cortex

cushing’s syndrome

hyper secretion of glucocorticoid hormones due to a pituitary tumor that overproduces ACTH

blood functions

1. Transport of dissolved substances (gases, nutrients, hormones, wastes)
2. Regulation of pH and ion composition
3. Restriction of fluid losses at injury sites (clotting)
4. Defense against toxins and pathogens (leukocytes)
5. Stabilization of body temp 

blood constituents

* plasma- 55%, least dense
* buffy coat-

coronary artery disease (CAD)

partial/complete block of coronary circulation → coronary ischemia

tunica intima

* innermost layer
* thin layer of endothelial cells
* contains sub endothelial layer of CT

tunica media

* middle layer
* smooth muscle cells, elastic fibers, collagen fibers
* arteries have THICK tunica media
* veins have THIN tunica media

tunica externa

* outer layer
* CT, including collagen & elastic fibers

elastic arteries

* conducting arteries
* 1-2.5cm
* large vessels (e.g., pulmonary trunk and aorta), tunica media has many elastic fibers and few muscle cells; evens out pulse 

muscular arteries

* distribution arteries
* 0.3-1cm,
* medium sized (most arteries)
* tunica media has many muscle cells  

arterioles

* small
* no longer a pulse, rather even flow
* 10μm-0.3mm, have little or no tunica externa
* thin or incomplete tunica media 

capillaries

* 8-10μm
* endothelial tube inside thin basal lamina
* only tunica intima (NO MEDIA OR EXTERNA)

venules

* 8-100μm
* collect blood from capillaries
* very small veins
* small ones (

medium-sized veins

* 2-9mm
* thin tunica media and few smooth muscle cells
* tunica externa with longitudinal bundles of elastic fibers 

large veins

* >9 mm
* thick tunica externa, thin tunica media 

continuous capillary function & location

* connect arteries to veins in circ system 
* Permit diffusion of water, small solutes, and lipid-soluble while blocking plasma proteins and blood cells  
* location: CNS, thymus, muscle and adipose tissue; some have very restricted permeability, e.g.m blood-brain barrier

fenestrated capillary function & location

* Permit rapid exchange of water and larger solutes between plasma and interstitial fluid 
* location: choroid plexuses, endocrine organs, kidneys, intestinal tract  

sinusoid capillary function & structure

* Permit free exchange of water, large plasma proteins and blood cells 
* location: liver, spleen, bone marrow, endocrine organs

where is most blood found at rest?

venous system

how does blood distribution change during hemorrhaging or vigorous exercise by the actions of the vasomotor center of the medulla oblongata or ANS?

blood reservoir can constrict to keep volume in capillaries & arteries near normal 

BP in pulmonary circulation

ca 15/8mm Hg

BP in arterial systemic

120/80 mm Hg

BP in the arteriole side of capillary

ca 35mm Hg

BP in venule of a capillary

ca 15-18mm

BP in veins

ca. 15-18mm

What helps to aid venous return to the heart in the systemic circulatory system?

It relies on skeletal muscle movement and valves in tunica intima to ensure 1-way movement

What structures allow blood to bypass pulmonary circulation in the fetus?

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1. Foramen ovale (minor bypass)


1. International opening; directs blood from right atrium to left atrium 
2. Covered by valve-like flap that closes after birth forming the fossa ovalis
2. Ductus arteriosus (major bypass)


1. Short vessel that connects pulmonary and aortic trunks 

what changes occur at birth?

* Newborn breathes air thereby expanding lungs 
* Pulmonary vessels expand reducing resistance and allowing for blood flow 
* Rising left atrium pressure closes foramen ovale 
* Muscular walls of the ductus arteriosus contract and eventually close in response to release of bradykinin (proinflammatory mediator typically associated with endothelial vasodilation) from the lungs after inflation and decrease in prostaglandin E₂ (PGE₂) and its receptor EP4, which help keep it open during fetal development 
* Pulmonary circulation now provides O₂

 Should these structures remain open after birth, what is the relative danger of each and why?

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1. In patent (open) foramen ovale, blood recirculates through pulmonary circuit instead of entering left ventricle 


1. Fairly common (up to 25% of population); not dangerous and typically asymptomatic 
2. A patent ductus arteriosus creates a large “right-to-left shunt”


1. Very dangerous; needs to be surgically corrected; symptoms not present at birth but show up in the 1st year of life; leads to pulmonary hypertension and right-sided heart failure

What structure’s in adults are remnants of these structures be familiar with the general circulatory pattern

* Foramen ovale → fossa ovalis 
* Ductus arteriosus → ligamentum arteriosum 


* Ductus venosus → ligamentum venosum 
* Umbilical arteries → medial umbilical ligaments 
* Umbilical vein → round ligament of the liver (ligamentum teres) 

lymph composition

all blood capillaries are surrounded by areolar CT that contains “tissue fluid” or “interstitial fluid” 

lymph function

keeps body fluid levels in balance and defends the body against infections

 pathway of circulation of lymph from start to finish

terminal lymphatic capillaries and progressing through lymphatic vessels (lymph capillaries →  lymphatic vessels → superficial lymphatics → deep lymphatic → lymphatic trunks, etc.) and ending in the left and right subclavian veins

What major lymphatic vessels are responsible for delivery of lymph from upper extremities, lower extremities and abdominopelvic areas?

* Subclavian trunks receive lymph from upper limbs and thoracic wall 
* Lumbar trunks (R & L) receive lymph from lower limbs 

T-cell lymphocytes

* thymus-dependent as they mature there (but made in bone marrow)
* Make up 80% of circulating lymphocytes


1. Function: 


1. bind to antigens that are presented by special proteins that occur only on the membranes of eukaryotic cells 
2. Recognize and respond only to foreign antigens 
3. Target “alien” cells- they reject transplanted organs, destroy our own cells that have been infected with viruses or other pathogens, and kill some cancer cells 

B cell lymphocytes

* B cells- bone marrow-derived 
* Make up 10-15% of circulating lymphocytes


1. Function: 


1. Produce “specific” antibodies in response to exposure to specific antigens (targets that identify pathogens or foreign compounds)
2. Plasma cells antibody production result in the binding of a specific antibody to its specific target (i.e., antigen) that then initiates antibody-mediated immunity, which results in destruction of pathogen
3. Respond primarily to bacterial and bacterial toxins 

NK cells lymphocytes

* natural killer cells 
* Make up 5-10% of circulating lymphocytes 


1. Function: 


1. Responsible for immunological surveillance 
2. Attack foreign cells, virus-infected cells, and cancer cells 
3. Part of the innate immune response as they can recognize stressed cells in the absence of antibodies and MHC, allowing for a much faster immune reaction; recognize cells that lack “self” cell surface molecules or certain glycoproteins 

cytotoxic T cells

attack eukaryotic cells infected by viruses, transplanted cells, and some cancer cells; produce cell-mediated immunity 

helper T cell

stimulate functions f T cells and B cells (secrete cytokine) 

suppressor-inducer T cells

inhibit function of T cells and B cells

regulatory T cells (TREGS)

helper and suppressor T cells; control sensitivity of immune response 

memory T cell

quickly respond to previously encountered antigens (antigen-experienced T cell)

B lymphocytes function

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1. Produce “specific” antibodies in response to exposure to specific antigens (targets that identify pathogens or foreign compounds)
2. Plasma cells antibody production result in the binding of a specific antibody to its specific target (i.e., antigen) that then initiates antibody-mediated immunity, which results in destruction of pathogen
3. Respond primarily to bacterial and bacterial toxins 

NK cells function

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1. Responsible for immunological surveillance 
2. Attack foreign cells, virus-infected cells, and cancer cells 
3. Part of the innate immune response as they can recognize stressed cells in the absence of antibodies and MHC, allowing for a much faster immune reaction; recognize cells that lack “self” cell surface molecules or certain glycoproteins 

how do lymphocytes become “activated”

when a lymphocyte’s antigen receptors bind its antigen that lymphocyte can be activated

primary lymphoid organs

bone marrow & thymus

secondary lymphoid organs

lymph nodes, spleen, tonsils, aggregated lymphoid nodules, appendix

major regions where lymph nodes are found

* cervical region
* axillary region
* inguinal region

lymph nodes functions

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1. Cleanse the lymph of pathogens 
2. Act as filters- purifies lymph before returning it to venous circulation


1. Removes: debris, pathogens, most antigenic challenges 
3. Distributed within body to monitor peripheral infections 
4. Respond before infections reach vital organs of trunk 

where is thymus located

in mediastinum

what is major function of thymus

Site where immature lymphocytes develop into T lymphocytes (thymosin & thymopoietin)

how does thymus function change with age?

atrophies after puberty (\~3% loss weight/year)- results in diminishing effectiveness of immune system with age 

major functions of the spleen

* Removal of abnormal or simply old blood cells and other blood components by phagocytosis 
* Destruction of antigens 
* Storage of iron recycled from RBCs 
* Storage of platelets 
* Initiation of immune responses by B cells and T cells 
* In response to antigens in circulating blood 

red pulp

contains many RBCs + fixed and free macrophages; responsible for destruction of worn-out RBCs

white pulp

 resembles lymphoid nodules; blood-borne antigens are destroyed as they activate the immune response

where is MALT

GI tract, nasopharynx, thyroid, breast, lung, tonsils, eye, & skin 

chylothorax

leakage of fatty lymph into the thorax, usually due to blockage or tear in thoracic duct (e.g., chest trauma)

lymphangitis

inflammation of a lymph vessel wall- becomes red as vasa vasorum vessels become congested

mononucleosis

viral disease caused by epstein-barr virus in saliva, infects B lymphocytes- T cells attack infected B’s

hodgkin’s lymphoma

cancer of lymph nodes- abnormal B’s (not painful)

Non-hodgkin's lymphoma

uncontrolled multiplication and metastasis of undifferentiated lymphocytes (B’s \[85%\], T’s \[15%\])- can be fatal in elderly

primary functions of the respiratory system

* External respiration (gas exchange between air & blood)
* Pulmonary ventilation (tidal movement of air into and out of lungs) 
* Protect respiratory surfaces from dehydration, temperature changes & pathogens 
* internal respiration
* Produce sound (communication)
* Provide olfactory sensation (smell)

upper respiratory system

external nares (nostrils) → nasal cavity → nasal vestibule → superior, middle, and inferior meatuses (meatuses warm & humidify incoming air while trapping particles bycreating air turbulences) →internal nares→ nasopharynx → oropharynx→ laryngopharynx → larynx

lower respiratory system

trachea → left/right primary bronchi → left/right lung → secondary bronchi → tertiary bronchi → bronchioles → alveolar ducts → alveoli

What mechanisms defend the delicate respiratory epithelium from particulate matter and pathogens?

* Mucous cells and mucous glands- produce mucus that bathes exposed surfaces 
* Cilia- sweeps debris trapped in mucus toward the pharynx (mucus escalator)
* Filtration- in nasal cavity removes large particles
* Alveolar macrophages- engulf small particles that reach lungs 

where are pneumatic bones found (those that contain sinuses), during what developmental age are the sinuses formed and what is their function?

* Pneumatic bones are found only in skull 
* Ethmoid sinus- present at birth
* Maxillary sinus- present at birth
* Frontal sinus- develops around age 7
* Sphenoid sinus- develops at adolescence
* Function: reduce facial skull weight, provide buffer against facial trauma, insulate dental roots and eyes to rapid temp changes, and involvement in immunological defenses 

What structures are involved in sound production?

Corniculate cartilage, glottis, vestibular fold, vocal fold, epiglottis, root of tongue, cuneiform cartilage, aryepiglottic fold

phonation

sound production at larynx

articulation

modification of sound by other structures- tongue, lips, teeth, cheeks + resonance and amplification by the pharynx, oral and nasal cavities, and sinuses 

Where are the tonsils located, what are their general functions?

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1. Pharyngeal tonsil:


1. Location: posterior wall
2. Function: destroys entering pathogens 
2. Palatine tonsils (tonsillectomy): 


1. Location: lateral walls of the fauces 
2. Function: help filter out germs that enter through your nose or mouth to protect the rest of body from infection
3. Lingual tonsils: 


1. Location: cover posterior surface of tongue 
2. Function: prevent infections

How is the pitch of phonation altered

* position arytenoid cartilage relative to thyroid cartilage changes pitch
* When distance ↑vocal folds tense → ↑ pitch
* When distance ↓ vocal folds relax → ↓ pitch 

right lung

* 3 lobes: superior, middle, & inferior
* Separated by horizontal and oblique fissures 
* Its wider than left and displaces upward by liver 
* Larger and heavier than left 

left lung

* 2 lobes: superior & inferior
* Separated by an oblique fissure 
* Longer than right and displaces leftward by heart forming the cardiac notch

regulatory mechanisms that govern air and blood flow to the respiratory exchange surfaces

trachea → left/right bronchus → secondary bronchus → tertiary bronchi → smaller bronchi → bronchioles → terminal bronchiole → respiratory bronchiole → alveoli in a pulmonary lobule 

Bronchioles

* Each tertiary bronchus branches into multiple bronchioles, which branch into terminal bronchioles (16th generation) 
* No cartilage (smooth muscle) 

Alveolus

* Connected to alveoli along alveolar ducts 
* Alveolar ducts end at alveolar sac
* Extensive network of capillaries
* Surrounded by elastic fibers 
* Alveolar pores allow for equalization of air pressure 

gas & blood supply

* Each lobule receives a pulmonary arteriole and a network of capillaries that surround each alveolus 
* BP in pulmonary circuit is low
* Pulmonary vessels are easily blocked by blood clots, fats, or air bubbles causing pulmonary embolism
* Blood flow through the pulmonary capillaries is slow and sheet like
* Diffusion occurs rapidly across the respiratory membrane because distance is short and gases are lipid soluble

conducting portion of respiratory system

nasal cavity to terminal bronchioles 

respiratory portion of respiratory system

* respiratory bronchioles & alveoli
* Gas exchange is possible here 

What are the three types of cells that make up the alveolar epithelium?

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1. Pneumocytes type I
2. Alveolar macrophages 
3. Pneumocytes type II

Which is responsible for modifying the surface tension?

Pneumocytes type II 

why is pneumocytes type 2 important for modifying surface tension

it helps keep the passageways to alveoli open 

What happens when there is insufficient surfactant?

the inner walls of an alveolus would stick together during exhalation 

external respiration steps

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1. Includes all processes involved in exchanging O2 and CO2 with the environment including: 
2. 1. Pulmonary ventilation (breathing in & out)
3. 2. Gas diffusion across membranes and capillaries 
4. 3. Transport of O2 and CO2 between alveolar capillaries & capillary beds in other tissues 

internal respiration steps

Involves the use of O2 as the terminal electron acceptor of the respiratory chain with the formation of H2O

pulmonary ventilation

physical movement of air into and out of respiratory tract; changes in pleural volume changes pressure resulting in air flow

inhalation

elevation of the rib cage and contraction of the diaphragm increase the size of the thoracic cavity. Pressure within the thoracic cavity decreases, and air flows into the lungs

exhalation

when the rib cage returns to its original position and the diaphragm relaxes, the volume of the thoracic cavity decreases. Pressure rises, and air moves out the lungs

Boyle’s law

(P=1/V)- pressure of a gas in a closed container at constant temperature is inversely proportional to the volume

intrapulmonary pressure

* relaxed breathing (eupnea): difference between atmospheric pressure and intrapulmonary pressure is typically small
* forced breathing (hyperapnea): can increase range from -30mm Hg for inspiration to +100 mm Hg expiration
* pressure in space between parietal and visceral pleura
* remains below Patm throughout respiratory cycle due to elastic fibers pulling lungs away from body wall

if intrapleural pressure becomes positive…

causes pneumothorax- an abnormal accumulation of air in the pleural space → breaks the seal created by the pleural fluid and lung collapses

Eupnea inhalation muscles

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1. Diaphragm


1. Contraction draws air into lungs 
2. 75% of normal air movement 
2. External intercostal muscles


1. Assists inhalation
2. 25% normal 
3. Accessory muscles assist in elevating ribs:


1. Sternocleidomastoid
2. Serratus anterior
3. Pectoralis minor
4. Scalene muscles 

Hyperpnea exhalation muscles

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1. Internal intercostal & transversus thoracis:


1. Depresses ribs 
2. Abdominal muscles:


1. Compresses abdomen & force diaphragm upward