Respiration and Excretion Flashcards
External respiration
exchange of oxygen and carbon dioxide between the air and the cells of the lungs.
Internal respiration
exchange of gases between body cells and the blood.
cellular respiration
chemical reactions in cells that use oxygen and produce carbon dioxide.
breathing or ventilation
the process by which air enters and leaves the respiratory organs
always involves a moist thin membrane
lower animals
single celled/smaller animals use diffusion alone to breathe through their moist skin or membrane ex) fish use their gills.
nasal chambers
air is filtered, warmed, and moistened by hairs, mucous, and sinus cavities
oral cavity
second entryway for air
larger opening for less filter
pharynx
area at the back of throat where both nasal and oral cavities open to
epiglottis
prevents the food from entering the trachea
trachea
the windpipe lined with rings of cartilage for support, lined with cilia to sweep debris away
also cilliated is the membranes of the upper respiratory passages
larynx
is the voicebox that contains vocal cords
bronchi
trachea branches into two bronchi, which then branch into smaller bronchi oles
no cartilage in bronchi oles they contain smooth muscle that contracts and expands with each breath
asthma
breathing condition that is from the over constriction of the smooth constricting muscle in the bronchi oles
alveoli
the air sacs at the end of the bronchi oles
single cell thick, moist, surrounded by a capillary bed- which is the site of gas exchange
surfactant
a lipoprotein secreted by lung tissue to prevent collapse of alveoli
pleural membranes
surround the lungs, have fluid between to reduce friction
gas exchange
gas moves from areas of high pressure to low pressure
pleural pressure = pressure in the lungs
atmospheric pressure = air pressure outside the lungs
inspiration vs. expiration
inspiration occurs when pleural pressure is less that atmospheric pressure
expiration occurs when pleural pressure is greater that atmospheric pressure
diaphragm
a dome shaped muscle at the base of the ribcage
intercostal muscles
are between ribs
inspiration
diaphragm contracts and moves downward
intercostals move ribcage up and out
the net result is an increase in lung volume and a decrease in pleural pressure
air moves into the lungs
expiration
diaphragm relaxes and domes up
intercostal muscles relax
the net result is a decrease in lung volume and an increase in pleural pressure
gas moves out
regulation of breathing- brain
chemorecptors in medulla detect carbon dioxide, as carbon dioxide levels increase the nerves from the brain send messages to respiratory muscles to increase breathing rate
regulation of breathing- heart
oxygen recptors in the aorta and carotid arteries are a back up for when CO2 stays normal but oxygen is low ex) high altitude
oxygen transport
oxygen binds with hemoglobin to form oxyhemoglobin, each hb molecule can carry four oxygen molecules
oxyhemoglobin dissociation
hemoglobins affinity for oxygen decreses as the acidity (carbon dioxide levels) increase
oxygen delivery increases to tissues in need
carbon dioxide transport ways it’s carried
20x more soluble than oxygen
carried in three ways:
1. some dissolved in blood plasma
2.combines with hemoglobin
3. most combines with water in the plasma to form carbonic acid which then breaks down into bicarbonate ions
reaction is catalysed by carbonic anhydrase enzyme
carbon monoxide
competes with oxygen for sites on hemoglobin- carboxyhemoglobin
200x more affinity for hb than oxygen
high altitude
body adapts by:
short term- increseing force and rate of breathing
increasing production of rbcs using hormone erythropoetien
increases lung capacity
the process by which the body rids itself of metabolic wastes
- lungs eliminate carbon dioxide
- large intestine eliminates toxic digestive waste
- liver deaminates amino acids to form ammonia
- kidneys remove urea and uric acid
ureters
tubes from kidneys to bladder, have muscular walls- peristalsis, about 25 cm long
bladder
stores urine- holds up to 600 ml
urethra
from bladder to exterior- longer in males 20 cm vs. 4 cm- less infections get to bladder
kidneys
2 of them
removes metabolic wastes from blood and regulates pH and water balance
the nephron
microscopic filters - 1 million in each kidney
regions of kidney
1) cortex- outermost, contains most parts of nephrons
2) the medulla- middle region, contains loop of henle, collecting ducts of nephrons
3) renal pelvis- the mostly hollow inermost region, collecting ducts merge to form ureter
micturition
the voluntary release of spintchers controlling the urine output from bladder
also aided by contraction of bladder wall
formation of urine
done by the nephrons
three stages: filtration, reabsorbtion, and secretion
filtration
high blood pressure in the glomerulus forces small molecules out of the blood and into Bowman’s capsule, water ions, amino acids, urea, and glucose can pass into Bowman’s capsule. red, white blood cells and platelets cannot. somethings wrong if they do.
reabsorbtion
essential nutrients and water is reabsorbed into the blood stream and distributed to the body at the main site of proximal convoluted tubule
secretion
activly transporting materials back into urine from the blood ex) nitrogenous waste, water
proximal tublue secretes H+ which helps maintain pH, blood is neutral and H+ makes it acidic so it must be.
Aldosterone homone
secreted from the cortex of the adrenal glands when blood pressure is low- it causes the DCT and collecting ducts to increase na transport into blood. chloride ions and water flow passively. the net result is blood pressure increases and urine output decreases,concentration increases
Antidiurcetic hormone
produced by hypothalamus, stored in posterior pituitary gland. h monitors water content of blood and adh is release when body is dehydrated. adh makes the nephron more permeable to water so more is reabsorbed, and as a result the urine is more concentrated. diuretics like alcohol and caffine inhibit adh production so urine output increases.
diabetes mellitis
inadequate secretion of insulin, without insulin blood glucose levels are high and excess glucose remains in the nephron. the high osmotic gradient prevents water reabsorbtion and increases urine production
diabetes insipidus
lack of adh production, urine output increases up to 20L per day, no sugar in urine
nephritis
inflammation of the nephrons, osmotic gradient causes increase in urine, and protein in urine is a common symptom- can lead to kidney damage.
hemopdialysis
artificial kidney machine connects to a vein and pumps blood through semipermeable tubes submerged in a solution to remove waste.
peritoneal dialysis
a catheater is inserted through abdominal lining, fluid is injected to collect waste and is drained.
kidney stones
crystallized oxalic acid or calcium or phosphate. can be surgical removed, drugs to dissolve or shock waves lithotripsy
