lecture exam 3
Antigen presenting cells
-T cells need APC's to recognize antigens; APC's function relies on a family of genes called the major histocompatibility complex (MHC) on chromosome 6. these genes code for MHC proteins- proteins on PAC surface that are shaped like hot dog buns. -when an APC encounters an antigen, it internalizes it via endocytosis, digests it into molecular fragments, and displays the relevant fragments (epitopes) in the grooves of the MHC proteins. These steps are called antigen processing. Wandering T cells regularly inspect APCs for antigens. If ACPs display a non-self antigen, T cells attack
trachea
-a rigid tube anterior to the esophagus -it is supported by 16-20 C-shaped rings of hyaline cartilage -the trachealis (the gap in the C) allows for the esophagus to expand as swallowed food passes by -inner lining is psuedostratified columnar epithelium composed mainly of mucus secreting goblet cells -the trachea traps debris in the mucus cells and drives it upward toward the pharynx
functions of aldosterone
-acts on thick segment of nephron loop, DCT and cortical portion of collecting duct -stimulates reabsorption of Na+ and secretion of K+, water and Cl- follow the Na+ -net effect is that the body retains NaCl and water (helps maintain blood volume/pressure) -urine volume is reduced -urine has an elevated K+ concentration
3 smaller paired cartilages of the larynx
-aryetnoid cartilage: posterior to thyroid cartilage -corniculate cartilage: attached to arytenoid cartilages like a pair of little horns -cuneiform cartilage: support soft tissue between arytenoids and epiglottis
relationship between high altitude and pressures of gases
-at high altitudes, the partial pressures of all gases are lower; gradient difference is less, and less oxygen diffuses into the blood
location, structure, and general function of spleen
-bodies largest lymphatic organ; spleen fits snugly between diaphragm, stomach, and kidneys. It presents red pulp which consists of sinuses gorged with concentrated erythrocytes and white pulp which consists of lymphocytes and macrophages. the spleen is the erythrocyte graveyard; macrophages phagocytize the remains of the erythrocytes. The lymphocytes and macrophages of the white pulp monitor the blood for antigens just as the lymph nodes do. the spleen is where monocytes stand and wait in a state of preparedness. In the event of infection, myocardial infarction, or wounds, angiotensin II stimulates spleen to release monocytes.
functions of electrolytes
-chemically reactive and participate in metabolism -determine electrical potential across cell membrane -affect osmolarity of body fluids -affect body's water content and distribution
regulation of fluid output
-controlled by kidneys; they cannot replace water or electrolytes but they can slow the rate of water and electrolyte loss until water and electrolytes can be ingested
location, structure, and general functions of the lymphoid tissues
-diffuse lymphatic tissue is common in respiratory, digestive, urinary, and reproductive tracts (MALT tissue- mucous associated lymphatic tissue) -lymphatic nodules (dense masses of macrophages and lymphocytes) are a feature of the lymph nodes, tonsils and appendix; Aggregated lymphoid nodules=dense clusters in ileum, the distal portion of the small intestine
how do gasses move during alveolar gas exchange
-down their concentration gradients; O2 concentration is higher in alveolus than in blood so O2 will go towards blood; and vice versa- CO2 goes from bloods stream to alveolus
nephrons
-each nephron has 2parts: -corpuscle: filters the blood plasma -tubule: long, coiled tube that converts the filtrate into urine -- renal corpuscle consists of glomerulus and a two layered glomerular capsule that encloses the glomerulus; parietal outer layer of glomerular capsule is simple squamous, visceral inner layer is podocytes that wrap around the capillaries of the glomerulus
cartilages of the larynx
-epiglottic cartilage: spoon shaped supportive plate in epiglottis; most superior one -thyroid cartilage: largest, laryngeal prominence (Adams apple); shield shaped -Circoid cartilage: connects larynx to trachea, ring-like
3 filtration components of membrane
-fenestrated endothelium of glomerular capillaries -basement membrane -filtration slits
renal plexus sympathetic innervation
-from abdominal aortic plexus -stimulation reduces glomerular blood flow and rate of urine production -respond to falling blood pressure by stimulating the kidneys to secrete renin, an enzyme that activates hormonal mechanisms to restore blood pressure
renal arteries
-interlobar arteries: up renal columns, between pyramids -arcuate arteries: over pyramids -cortical radiate arteries: up into cortex -branch into afferent arterioles: each supplying one nephron -- leads to a ball of capillaries (glomerulus)
functions of Ca+
-lends strength to skeleton -cells need to maintain low Ca+ level to prevent calcium phosphate crystal precipitation -cells must pump out Ca++
compare plasma, interstitial fluid, and lymph
-lymph is a clear, colorless fluid, similar to blood plasma but low in protein. It originates as tissue fluid taken up by the lymphatic vessels; lymph contains macrophages, hormones, viruses, cellular debris, etc.
relaxed breathing
-passive process achieved mainly by elastic recoil of thoracic cage; recoil compresses the lungs; volume of thoracic cavity decreases; raises intrapulmonary pressure to about 1 cm; air flows down the pressure gradient and out of lungs
metabolic water and preformed water:
- by product of aerobic metabolism and dehydration synthesis -comes from ingested food
juxtamedullary nephrons
-15% of all nephrons -very long nephron loops, maintain salinity gradient in the medulla and help conserve water -efferent arterioles branch into vasa recta around long nephron loop
T cell activation
-Antigen recognition: T cell binds to an APC displaying an antigen fragment -Costimulation: T cell binds to a second protein on the APC -clonal selection: T cell undergoes repeated mitosis and produces a large number of effector cells and memory T cells -attack: effector T c cells attack and destroy abnormal cells with a lethal hit; T h cells secrete interleukins that stimulate multiple forms of attack
B cells
-B cell maturation occurs entirely in the red bone marrow
structure and function of lymphatic vessels
-Larger ones composed of 3 layers: tunica interna, tunica media, and tunica externa -Collecting vessels course through many lymph nodes -Exercise significantly increases lymphatic return -Six lymphatic trunks drain major portions of the body: Jugular, subclavian, bronchomediastinal, intercostal and lumbar trunks -they are closed at one end
CO2 in transport
CO2 and H2O is converted to carbon acid via carbonic anhydrase- carbonic acid then dissociates into bicarbonate ions and H+; 5% is bound to proteins, 5% is dissolved In gas/plasma
major anions
Cl-, HCO3- (bicarbonate), and PO43-
functions of lymphatic system
Fluid recovery- fluid continually filters from the blood capillaries into the tissue spaces → 15% is absorbed into lymphatics Immunity- excess filtered fluid picks up foregin cells and chemicals from the tissues Lipid absorption- lacteals in small intestine absorb dietary lipids that are not absorbed by the blood capillaries
natural active immunity
Production of one's own antibodies or T cells as a result of infection or natural exposure to antigen
Artificial active immunity
Production of one's own antibodies or T cells as a result of vaccination against disease
hypothalamus produces:
ADH which promotes water conservation; cerebral cortex produces conscious sense of thirst -salivation is inhibited with thirst
interleukins
APCs and lymphocytes talk to each other with cytokines called interleukins- chemical signals from one leukocytes to another
Natural passive immunity
Temporary immunity that results from antibodies produced by another person Fetus acquires antibodies from mother through placenta, milk
Artificial passive immunity
Temporary immunity that results from the injection of immune serum (antibodies) form another person or animal
location, structure, and general function of thymus
located between sternum and aortic arch in superior mediastinum; the fibrous capsule of the thymus gives off trabecular that divide the gland into several lobes; each lobe has a light central medulla (with T lymphocytes) and dark outer cortex. In cortex, the cortical epithelial cells and capillary pericytes surround blood capillaries and form blood-thymus barrier which isolates developing lymphocytes from premature exposure to antigens. After developing in the cortex, T lymphocytes migrate to the medulla . T cells enter blood or lymphatic vessels here and leave thymus; epithelial cells of the thymus secrete signaling molecules which promote the development and action of T cells both locally an systemically (thymosin, thymopoietin, thymulin, interleukins, interferon)
the route from the tissue fluid back to the blood stream is:
lymphatic capillary--> collecting vessels --> 6 lymphatic trunks --> two collecting ducts --> subclavian veins
Describe anatomical features of lymphoid tissue
lymphatic tissues are aggregations of lymphocytes in the connective tissues of mucous membranes and various organs -simplest form is diffused lymphatic tissue in which lymphocytes are scattered around rather then densely packed -has reticular tissue, which are branched cells that contribute to the connective framework
inspiratory capacity
maximum effort of air that can be inhaled after a normal tidal expiration (IC= TV + IRV)
total lung capacity
maximum effort of air the lungs can contain (TLC = RV +VC)
PCT absorbs:
about 65% of glomerular filtrate and removes some substances from blood and secretes them into tubular fluid for disposal
tachypnea
accelerated respiration
forced breathing
accessory muscles raise intrapulmonary pressure as high as +40 cm
functions of phosphates
activates many metabolic pathways; they stabilize pH of body fluids --> shuttles energy
GFR is controlled by:
adjusting glomerular blood pressure from moment to moment; control is achieved by 3 homeostatic mechanisms: -renal autoregulation -sympathic control -hormonal control
alveolar ventilation rate
air that ventilates alveoli (350mL) X respiratory rate (12 ppm) =4,200 mL/min -this measurement is crucially relvevant to the body ability to et oxygen to the tissues and dispose of CO2
sodium concentration coordinate by:
aldosterone: it saves the sodium and pees the potassium; primary job is to regulate sodium secretion
emphysema
alveolar walls break down and the alveoli converge into fewer and larger spaces; thus there is less respiratory membrane available for gas exchange.
four factors adjust the rate of oxygen unloading to match need
ambient, temperature, the Bohr effect, concentration of biphosphoglycerate (BPG)
expiratory reserve volume
amount of air in excess of tidal volume that can be exhaled with maximum effort
inspiratory reserve volume
amount of air in excess of tidal volume that can be inhaled with maximum effort
tidal volume
amount of air inhaled and exhaled in one cycle during quiet breathing
minute respiratory volume
amount of air inhaled in 1 minute TV X respiratory rate- MV
residual volume
amount of air remaining in lungs after maximum expiration; the amount that can never be voluntarily exhaled; allows for some gas exchange with blood before next breathe of fresh air
functional residual capacity
amount of air remaining in the lungs after a normal tidal expiration (IC=TV+ IRV)
functions of Cl-
most abundant anion; major contributors ECF osmolarity, required for the formation of stomach acid (HCL); regulates body pH
glomerular filtration rate
amount of filtrate formed per minute by the two kidneys; if GFR is too high, the fluid flows through tubules too quickly so water and solutes don't have time to reabsorb so there is an increase in urine and dehydration and electrolyte depletion; if GFR is too low, wastes are reabsorbed
proximal convoluted tubule
arises from glomerular capsule- longest one (simple cuboidal epithelium)
hypercapnia
most common cause of acidosis; PCO2 greater than 43 mmHg
hypocapnia
most common cause of alkalosis; PCO2 less than 37 mmHG
potassium imbalances
most dangerous types of electrolyte balance
Major fluid compartments of the body
most is in intracellular space (65%) and 35% is extracellular
ambient pH
as pH drops, and theres a more acidic environment, this decreases oxygen binding to hemoglobin; active tissues generate extra CO2, which raises the H+ concentration and lowers pH. hydrogen ions of the low pH weaken the bond between hemoglobin and oxygen and thereby promote oxygen unloading (Bohr effect)
temperature
as temp increases, hemoglobin more readily gives up oxygen
alveolar macrophages
most numerous cells in the lungs; they wander the lumen of the alveoli and the connective tissue between them, These cells keep the alveoli free of debris by phagocytizing dust particles
collecting ducts
begin in the cortex; runs through medulla and reabsorbs water, making urine up to 4 times more concentrated -as urine passes through increasingly salty medulla, water leaves by osmosis, concentrating urine
distal convoluted tubule
beings after ascending limber reenters the cortex; cuboidal epithelium
antidiuretic hormone (ADH)
stimulated by dehydration, loss of blood volume, etc. -ADH released, makes collecting duct more permeable to water -water in tubular fluid then reenters the tissue fluid and bloodstream
functions of Na+
super important in establishing resting membrane potential; inflow of sodium through membrane gates is an essential even of depolarization -Na+, K+ pump is an important means of generating body heat; pumps Na+ out of cell and K+ into cell
apnea
temporary cessation of breathing
blood leading away from glomerulus
blood is drained from glomerulus by efferent arteries -most efferent arterioles lead to peritubular capillaries --some efferents lead to vasa recta ( a network of blood vessels within renal medulla) -capillaries then lead to cortical radiate veins or directly into arcuate veins -arcuate veins lead to interlobar veins which lead to renal vein -renal vein empties into inferior vena cava
sum of all the pressures
blood is filtered out; net filtration is out of kidneys
alkalosis
blood pH > 7.45
acidosis
blood pH below 7.35
glycosuria
blood sugar over 220 mg/dL= glucose in your urine because the transporters of the solutes are overwhelmed so glucose comes out in urine
cyanosis
blueness of the skin; hypoxia is often marked by cyanosis
two factors that influence airway resistance:
bronchiole diameter- can be increased- (bronchiodilation or decrease- branchoconstriction) pulmonary compliance- ease with which lungs expand; the change in lung volume relative to a given pressure change; compliance is limited by the surface tension of the water film inside alveoli- if there is a problem with surfactant, this reduces compliance of the lungs
how does fluid move between compartments
by osmosis- because water moves so easily through membranes, osmotic gradients never last long; if imbalance arises, osmosis restores balance within seconds
ventilation-perfusion coupling
the ability to match air flow and blood flow to each other; gas exchange requires both good ventilation of alveolus and good perfusion of the capillaries; pulmonary blood vessels change diameter depending on air flow to an area of lungs (if poorly ventilated, vessels constrict); bronchi change diameter depending on blood flow to an area of the lungs (if an area is well perfused, bronchodilation occurs)
micturition
the act of urinating
third line of defense
the adaptive immunity -specialized lymphocytes (T cells & B cells) -Antibodies
vital capacity
the amount of air that can be inhaled and then exhaled with maximum effort; the deepest possible breathe (VC= ERV + TV +IRV)
respiratory membrane
the barrier between the alveolar air and blood is called respiratory membrane; consists of squamous alveolar cells, the squamous endothelial cell of the capillary, and their shared basement membrane
between acts of urination...
the bladder fills -detrusor muscle relaxes -urethral sphincter closes tightly
cytotoxic T cells
the effectors of cellular immunity that carry out the attack on foreign cells
boyles law
the pressure of a given quantity of gas is inversely proportional to its volume (assuming a constant temp)
aldosterone
the salt retaining hormone -steroid secreted by the adrenal cortex triggers for aldosterone secretion are: -blood Na+ concentration falls -K+ concentration rises OR drop in blood pressure--> renin release--> angiotensin II formation--> stimulates adrenal cortex to secrete aldosterone
Intrapleural pressure
the slightly negative pressure that exists between two pleural layers; recoil of lung tissue and tissues of thoracic cage causes lungs and chest wall to be pulling in opposite directions; the small space between the parietal and visceral pleura is filled with water fluid, so these layers stay together; about -5 cm of intrapleural pressure results
location, structure, and general function of tonsils
the tonsils are patched on lymphatic tissue located at entrance of pharynx where they guard against ingested and inhaled pathogens; Each is covered by an epithelium and has deep pits called tonsillar crypts lined by lymphatic nodules; the crypts often contain food debris, dead leukocytes, bacteria and antigenic chemicals. 3 main sets of tonsils: pharyngeal tonsil on the wall of the.pharynx just behind nasal cavity, palatine tonsil at the posterior margin of the oral cavity, and the lingual tonsils concentrated in patches embedded in each side of the root of the tongue --> palatine are most often removed
describe how ventilation will be regulated in response to a decrease in pH below 7
this is a response to acidosis; we hyperventilate in order to blow off CO2 ; thus the H+ is consumed, and as H+ declines, the pH rises and returns blood pH to normal
the renin-angiotensin-aldosterone mechanism
this mechanism is a system of hormones that helps control blood pressure and GFR -in response to a drop in blood pressure, baroreceptors in carotid and aorta stimulate the sympathetic nervous system -sympathetic fibers trigger release of renin by kidney's granular cells -renin converts angiotensinogen into angiotensin 1 -angiotensin 1 goes to lungs, in lungs it is converted to angiotensin 2 -angiotensin 2 stimulates hypothalamus, is a vasoconstrictor, and also stimulates adrenal gland to release aldosterone which stimulates kidneys for sodium and water retention --> all of this results in elevated blood pressure
alveoli
tiny air sacs in lungs allowing for gas exchange
daltons law
total atmospheric pressure is the sum of the contributions of the individual gasses
urea and uric acid
uric acid is from nucleic acid breakdown and urea is from protein breakdown
path of urine
urine is made in pyramidal renal medulla, drains into the minor calyx, then to the major calyx then drains down to the renal pelvis then drains down the major ureter
vasa recta
capillary branching off efferent arteriole in medulla; descending capillaries of vasa recta exchange water for salt, water diffuses out and salt diffuses in; ascending capillaries of vasa recta exchanges salt for water
CO2 transported in 3 forms
carbonic acid, carbamino compounds, dissolved plasma ; 90% is hydrated to form carbonic acid- 5% binds to the amino groups of plasma proteins to form carbamino compounds
how are odors detected
via the olfactory epithelium, which covers a small area of the roof of the nasal fossa and adjacent parts of the septum and superior concha. the rest of the nasal cavity, except for the vestibule is lined with respiratory epithelium.
larynx
cartilaginous chamber; primary function is to keep food and drink out of airway -the superior opening of the larynx is guarded by a flap of tissue called the epiglottis -the framework of the larynx consists of 9 cartilages; the first three are solitary and relatively large. -the walls of the larynx are quite muscular
where are lymph nodes most concentrated?
cervical lymph nodes-occur in deep and superficial groups in the neck axillary lymph nodes- in armpit and receive lymph from upper limb and breast thoracic lymph nodes- occur in thoracic cavity, especially in mediastinum abdominal lymph nodes- occur in posterior abdominopelvic wall and receive lymph from urinary and reproductive tract intestinal and mesenteric lymph nodes- found in mesenteries and adjacent to appendix and intestines inguinal lymph nodes-occurs in the groin popliteal lymph nodes- occur at back of the knee
atelectasis
collapse of a lung; can also result from an airway obstruction as blood absorbs gases from blood
carbon monoxide
competes for the binding sites on the hemoglobin molecule (competitive inhibition) - so oxygen cannot bind and thus cannot be transported to the tissues
vaccine
consists of dead of attenuated (weakened) pathogens that stimulate the immune response without causing the disease
innate immunity
consists of defenses we are born with
adaptive immunity
constitutes 3rd line of defense; it adapts the body to the presence of environmental pathogens
sympathetic nervous system and adrenal epinephrine:
constrict the afferent arterioles in strenuous exercise of acute conditions like circulatory shock -reduces GFR -redirects blood form kidneys to heart/brain
short term inhibition of thirst
cooling and moistening of mouth quenches thirst; distension of stomach and small intestine
cuboidal great (type II) alveolar cells
cover 5% of surface area, squamous cells cover more AREA but great cells are more numerous. two functions: they repair the alveolar epithelium when the squamous cells are damaged AND they secrete pulmonary surfactant, a mixture of phospholipids and protein that coats the alveoli and smallest bronchioles and prevents the bronchioles form collapsing when one exhales
squamous (type 1) alveolar cells
cover 95% of the alveolar surface area. their thinness allows for rapid gas diffusion between the air and blood
Kussmaul respiration
deep, rapid breathing often induced by acidosis
filtration pressure
depends on hydrostatic and osmotic pressures on each side of the filtration membrane; there is also colloid osmotic pressure of blood
memory T cells
descended from T c cells and are responsible for memory in cellular immunity. Thus they sustain the body vigilance against a given pathogen without causing the damage that a persistent population of T c cells would do.
nephron loop
descending and ascending limb (U shaped portion); thick segments are simple cuboidal, thin segments are simple squamous
spirometer
device that recaptures expired breath and records variables such as rate and depth of breathing, speed of expiration and rate of oxygen consumption
nasopharynx
distal to the posterior nasal apertures and above soft palate; inhaled air turns downward 90 degrees. usually large particles cannot turn so they stick to the mucous membrane on the back of the nasopharynx; passes only air, and is lined by pseudostratified ciliated columnar epithelium
renal tubule
duct leading away from the glomerular capsule and ending at the tip of the medullary pyramid; divided into four regions: proximal convoluted tubule, nephron loop, distal convoluted tubule, collecting duct (receives fluid from many nephrons)
anemic hypoxia
due to anemia and the resulting inability of the blood to carry adequate oxygen
pontine respiratory group (PRG)
each side of pons receives input from nigher brain centers and issues output to both DRG and VRG; it hastens or delays the transition from inspiration to expiration, making each breath short and shallower or longer and deeper.
azotemia
elevated blood urea nitrogen; may indicate renal insufficiency
expiration
exhaling
functions of kidneys
filter blood/excrete toxic metabolic wastes; regulate blood volume, pressure, and osmolarity; secrete erythropoietin
structure/function of nose:
functions: warms, cleanses, humidifies inhaled air; detects odor, amplifies voice structure: it extends from a pair of anterior openings called nostrils (nares) to a pair of posterior openings Called the posterior nasal apertures (choanae) -shaped by bone and hyaline cartilage -flared sides of nose are called Ala nasi -internal nose is called nasal cavity divided into right and left halves called nasal fossae- dividing wall is called the septum -the nasal cavity begins with a small dilated chamber called vestibule; this space is lined with stratified squamous epithelium and has stiff guard hairs (vibrissae). -the narrowness of the passages ensures air most air contacts the mucous membrane; the conchae enables nose to clean the air.
primary function of nephron loop
generate salinity gradient that enables collecting duct to concentrate the urine and conserve water
flow of fluid from the point where the glomerular filtration is formed to the point where urine leaves body:
glomerular capsule--> proximal convoluted tubule --> nephron loop--> distal convoluted tubule--> collecting duct--> papillary duct--> minor calyx--> major calyx--> renal pelvis--> ureter--> urinary bladder --> urethra
tubuloglomerular feedback auto regulation:
glomerulus receives feedback on the status of downstream tubular fluid and adjusts filtration rate accordingly; juxtaglomerular apparatus: complex structure found at end of nephron loop where it has just reentered renal cortex; it has macula dense (sensory cells in nephron loop)
deoxyhemoglobin
hemoglobin with no oxygen bound to it
hyperkalemia
high potassium; can cause cardiac arrest
what does sodium reabsorption determine:
how concentrated urine is; sodium reabsorption is key- it creates an osmotic and electrical gradient that drives the reabsorption of water and other solutes
tubular fluid arriving at DCT from loop of henley is:
hypotonic fluid
hyperpnea
increases rate/ death of breathing in response to exercise, pain, or other conditions
inspiration
inhaling
micturition reflex
involuntary spinal reflex that partly controls urination
dyspnea
labored, gasping breathing, shortness of breath
shape of kidney
lateral surface is convex and medial is concave with a slit called hilum
second line of defense:
leukocytes, macrophages, antimicrobial proteins, natural killer cells, fever, inflammation
laryngopharynx
lies mostly posterior to the larynx. the esophagus begins here ; passes food and drink; lined by stratified squamous epithelium
Regulatory T cells
limits the immune response by inhibiting multiplication and cytokine secretion by other T cells. Once a pathogen is defeated it is important to down regulate T cytotoxic activity; T r cells reduce risk of autoimmune diseases
dorsal respiratory group (DRG)
web of neurons that extends for much of the length of the medulla between VRG and central canal or the brainstem; breathing rate changes, and the DRG is an integrating center that receives input from several sources: respiratory center in the pons, chemoreceptors in major arteries, stretch and irritant receptors, and nigher brainstem centers; the DRG issues out input to the VRG that modifies respiratory rhythm
macula densa
when GFR is high, filtrate contains more NaCl; when macula dense absorbs more NaCl, it secretes ATP; ATP is metabolizes by nearby mesangial cells into adenosine; adenosine stimulates nearby granular cells; granular cells respond to adenosine by contracting afferent arterioles, reducing blood flow which corrects GFR
renal auto regulation
where nephrons adjust their own blood flow and GFR without external contro; enables kidneys to maintain a relatively stable GFR in spite of changes in systemic blood pressure
oropharynx
space between the posterior margin of the soft palate and epiglottis; passes food and drink; lined by stratified squamous epithelium
Osmosis from one fluid compartment to another is determined by
relative concentrations of solutes in each compartment: -electrolytes: the most abundant solute -sodium salts in ECF -potassium salts in ICF
eupnea
relaxed quiet breathing
conversion of glomerular filtrate to urine involves:
removal and addition of chemicals by tubular reabsorption and secretion -occurs through PCT and DCT -tubular fluid is modified
tubular secretion
renal tubule extracts chemicals from capillary blood and secretes them into tubular fluid -purpose of secretion in PCT and nephron loop= --acid base balance --waste removal --clearance of drugs/contaminants
respiratory zone
respiratory bronchiole--> alveolar duct--> atrium--> alveolus all of the passages have alveoli on their walls and thus engage in gas exchange
glomerular filtration
special case of capillary fluid exchange in which water and some solutes in the blood plasma pass from capillaries of the glomerulus into the capsular space of the nephron
collecting ducts
several nephrons joining together; they receive fluid from several nephrons; numerous collecting ducts converge toward the tip of the medullary pyramid -papillary ducts: formed by merger of several collecting ducts
excretion body systems
respiratory system- CO2 excretion integumentary systen- water, inorganic salts, arctic acid, urea in sweat digestive system- water, salts, CO2, lipids, metabolic wastes urinary system- many metabolic wastes, toxins, drugs, etc
peripheral and central chemoreceptors
respond to changes in pH, CO2 and O2 (pH is most sensitive, then CO2)
ischemic hypoxia
results from inadequate circulation of the blood, as in congestive heart failure
hypokalemia
results from sweating, vomiting, diarrhea, etc.; nerve muscles less excitable- muscle weakness, etc.
ureters
retroperitoneal, muscular tubers that extend from each kidney to the urinary bladder
natriuretic peptides
secreted by atrial myocardium of the heart in response to high blood pressure -results in the excretion of more salt and water in the urine, thus reducing blood volume and pressure
PTH
secreted in response to calcium deficiency; acts on PCT to increase phosphate excretion and on the DCT to increase calcium reabsorption
respiratory epithelium in nasal cavity
secretes mucus via goblet cells
cell-mediated immunity
- a form of adaptive immunity in which T cells directly attack and destroy diseased/foreign cells and the immune system remembers the antigens of those invaders and prevents them from causing disease in the future
long term inhibition of thirst
- absorption of water form small intestine reduces osmolarity of blood; stops osmoreceptor response, promotes capillary filtration, makes saliva more abundant and watery
ambient air
since vatic tissue consumes O2 readily, the PO2 of the tissue fluid remains low; at a low PO2, HbO2 releases more oxygen
first line of defense:
skin, and mucous membranes
BPG
a metabolite from erythrocytes; a lot of BPG promotes oxygen unloading
humoral immunity
a more indirect method of defense than cellular immunity- B lymphocytes of humoral immunity produce antibodies that bind to antigens and tag them for destruction by other means
T cells
-produced in red bone marrow, mature in thymus -upon arrival to thymus, T cells go first to the thymus cortex and cluster on cortical epithelial cells. The epithelial cells test the young T cells to see which ones will be capable of later recognizing foreign antigens and antigen presenting cells. T cells that cannot recognize it get the chance to retake the test by shuffling their DNA. if they fail again, they die. Those that pass are called immunocompetent -the cortical process of selecting T cells that are immunocompetent is called positive selection -these T cells them go to the medulla and get tested again to see if they will attack ones own body. elimination of self-reactive T cells is called negative selection. -the few survivors of these tests multiply.These naive T cells (haven't yet encountered an antigen) leave thymus by way of blood and lymphatic vessels, disperse throughout the body, and colonize lymphatic tissues/organs. *called cell-mediated*
the countercurrent multiplier
-the ability of kidneys to concentrate urine depends on salinity gradient in renal medulla -nephron loop acts as countercurrent multiplier -countercurrent: because of fluid flowing in opposite directions in adjacent tubules of nephon loop -multiplier: continually recaptures salt and returns it to extracellular fluid of medulla which multiplies the osmolarity of adrenal medulla
regulation of fluid intake
-thirst -dehydration; reduces blood volume/pressure; increases osmolarity -osmoreceptors in hypothalamus; they respond to angiotensin II produced when BP drops and also respond to rise in osmolarity in ECF
3 layers of ureter
1. adventitia- connective tissue layer that connects ureter to surrounding structures 2. muscularis- two layers of smooth muscle with third layer in lower ureter 3. mucosa- transitional epithelium
humoral immune response events:
1. antigen recognition: immunocompetent B cells exposed to antigen. antigen binds only to B cells with complementary receptors 2. antigen presentation: B cell internalizes antigen and displays processed epitope. helper T cell binds to B cell and secretes interleukins 3. clonal selection: interleukin stimulates B cell to divide repeatedly and form a clone 4. differentiation: some cells of the clone become memory B cells. most differentiate into plasma cells 5. attack: plasma cells synthesize and secrete antibody. antibody employs various means to render the antigen harmless
3 layers of urinary bladder
1. covered by parietal peritoneum 2. muscularis: detrusor- three layers of smooth msucle 3. mucosa: transitional epithelium
functions of respiratory system:
1. gas exchange: it provides for O2 and CO2 exchange between blood and air 2. communication: serves for speed and other vocalization 3. olfaction: it provides the sense of smell 4. acid base balance: by eliminating CO2, it helps to control the pH of body fluids; if respiration doesn't keep pace with CO2 production, acid accumulates and body fluids have low pH (acidosis) 5. blood pressure regulation: the lungs carry out a step in synthesizing angiotensin II, which helps regulate blood pressure 6. blood and lymph flow: breathing creates pressure gradients between the thorax and abdomen that promote flow of lymph and venous blood 7. blood filtration: the lungs filter small blood clots from the bloodstream and dissolve them, preventing clots from obstructing pathways 8. expulsion of abdominal contents: breath holding and abdominal contraction help expel abdominal contents during urination,defecation, etc.
means to render the antigen harmless:
1. neutralization: means the masking of critical regions of an antigen molecule by antibodies. Only certain regions of an antigen are pathogenic- antibodies can neutralize an antigen by masking these active regions 2. complement fixation: an action in which antibodies bind complement proteins to an enemy cell, leading to its destruction; IgM and IgG bind to enemy cells and change shape, exposing their complement binding sites- makes it easier for phagocytes to ingest and destroy 3. agglutination: clumping of enemy cells by antibodies. this immobilizes microbes and prevents them from spreading; neutrophils and macrophages can phagocytize clusters. 4. precipitation: similar process by which antigen molecules are clumped by adhesion to antibodies. This creates large complexes that can be removed by immune clearance or phagocytize by eosinophils.
if a person inhales 500 mL of air how much air reaches alveoli
350 mL because 150 mL stays in anatomical dead space
CO2 in exchange
70% comes from carbonic acid, some from proteins, some from plasma
cortical nephrons
85% of all nephrons -short nephron loop -efferent arterioles branch into peritubular capillaries around PCT and DCT
intrapulmonary pressure
If the lungs contain a quantity of a gas and the lung volume increases, the internal pressure (intrapulmonary pressure) falls. If lung volume decreases, the pressure inside the lung increases and air moves outside of lungs
chronic bronchitis
a sever persistent inflammatory disease of lower respiratory tract; goblets cells of the bronchial mucosa enlarge and secrete excess mucus while at the same time, the cilia are immobilized and unable to discharge it; thick stagnant mucus accumulates in the lungs and furnishes a growth medium for bacteria
hypoxemia hypoxia
a state of lower PO2, usually due to inadequate pulmonary gas exchange
major cations
Na+, K+, Ca++, Mg++, H+
what can bind to hemoglobin
O2 and CO2
pneumonia
a lower respiratory infection; causes filling of alveoli with fluid of dead leukocytes and thickening of the respiratory membrane, which interferes with gas exchange and causes hypoxemia
location, structure, and general function of lymph nodes
most numerous lymphatic organs; serve 2 functions- to cleanse lymphocytes and act as a site of T and B cell activation. It is an elongated bean shaped structure, with an indentation called a hilum on one side. It is enclosed in a fibrous capsule with trabecular that partially divide the interior node into compartments. between the capsule and the parenchyma is a narrow relatively clear space called the sub scapular sinus, which contains reticular fibers, macrophages, and dendritic cells. deep to this, the gland consists mainly of a stroma of reticular connective tissue and a parenchyma of lymphocytes and antigen presenting cells. the cortex consists mainly of ovoid conical lymphatic nodules; when the lymph node is fighting a pathogen, these nodules acquire germinal centers where B cells multiply and differentiate into plasma cells. Afferent lymphatic vessels lead into the node and efferent lymphatic vessels lead out.
pharynx
muscular funnel extending from posterior nasal apertures to the larynx; 3 regions: nasopharynx, oropharynx, and laryngopharynx
myogenic mechanism of autogregulation:
myogenic mechanism- based on tendency of smooth muscle to contract when stretched; if arterial blood pressure increases- afferent arteriole is stretched, afferent arteriole constricts and prevents blood flow into the glomerulus from changing (way to regulate blood flow) -if arteriole pressure falls, afferent arterial relaxes, afferent arteriole dilates and allows blood to flow more easily in to glomerulus
conducting zone
nasal cavity--> pharynx--> trachea--> main bronchus--> lobar bronchus --> segmental bronchus--> bronchiole--> terminal bronchiole in this zone, there are no alveoli and the tissue walls are too thick for any significant exchange of O2 or CO2 with the body
nitrogenous waste reabsorption
nephron reabsorbs about half of urea in tubular fluid- concentration remaining in blood is safe; PCT reabsorbs uric acid, but later portions of the nephrons secrete it creatinine is not reabsorbed, it is passed in urine
body weight in newborn and men
newborn- 75% men- 55%-60%
what is most common element in air
nitrogen
what are the principal organs of respiratory system:
nose, pharynx, larynx, trachea, bronchi, lungs
histotoxic hypoxia
occurs when a metabolic poison such as cyanide prevents the tissues from using the oxygen delivered to them
hypovolemia
occurs when proportionate amounts of water and sodium are lost without replacement; total body water declines (hemorrhage, vomiting, diarrhea)
respiratory cycle
one complete in and out breath
gross anatomy of kidney
outer renale cortex inner renal medulla lobe of kidney: one pyramid and its overlying cortex minor calyx: cup that nestles the papillae of each pyramid; collects its urine major calyx: formed by convergence of 2 or 3 minor calyx renale pelvis: formed by convergence of 2 or 3 major calyx ureter: tubular continuation of the pelvis that drains urine into bladder
oxyhemoglobin
oxygen bound to hemoglobin
hypernatremia
plasma sodium concentration greater than 145 mEg/L
hyponatremia
plasma sodium concentration less than 130 mE1/L
pneumothorax
presence of air in pleural cavity; thoracic wall is punctured, inspiration sucks air through the wound into pleural cavity, potential space becomes an air-filled cavity, loss of negative intrapleural pressure allows lungs to recoil and collapse
ventral respiratory group (VRG)
primary generator of the respiratory rhythm; in the medulla - in quiet breathing, the neuron circuit fires for about 2 seconds at a time, issuing nerve signals to integrating centers in spinal cord. The spinal centers relay tsignals by way of intercostal nerves to the external intercostal muscles. contraction of these muscles enlarges thoracic cage and causes inspiration (THIS IS I NEURONS); once I neurons stops, E neurons take over and cause expiration of breathing- elastic recoil expels air form lungs.
tubular reabsorption
process of reclaiming water and solutes from tubular fluid and returning them to blood
creatinine
produced by breakdown of phosphate
functions of K+
produces (with sodium) resting membrane potentials and action potentials of nerve and muscle cells
helper T cells
promote the action of T cytotoxic cells as well as playing key roles in humoral and innate immunity.
cardiac output of kidneys
receive 21% of cardiac output
location, structure, and general functions of red bone marrow
red bone marrow is involved in hemopoiesis and immunity. in adults, red bone marrow is fund in the axial skeleton and the proximal heads of the humerus and femur; it is an important supplier of lymphocytes to the immune system. -red bone marrow is a soft loosely organized, highly vascular material. It produces all classes of formed elements. the sinusoids drain into the central longitudinal vein; the sinusoids are lined by endothelial cells and are surrounded by reticular cells/fibers; the reticular cells secrete colony stimulating factor that induce formation of various leukocyte types.
