Bio 102 exam 4 chapter 35

michelleburkee2's version from 2016-04-21 03:14

Section 1

Question Answer
2 functions of the urinary systemexcretion and to maintain homeostasis
osomlarity defconcentration of small molecules and ions in blood
metabolism of amino acids removes amino group as ammonia
what two groups are used for cellular respiration, glucose synthesis, and lipid synthesis after the ammonia is metabolized from the amino group?R groups and carboxyl groups
what is more toxic: urea or ammoniaammonia
what do fish secrete?ammonia*
what do mammals secrete?urea
what do birds secrete?uric acid
what type of urinary systems do flat worms haveprotonephridia
what type of urinary systems do insects have?malpighian tubules
what type of urinary systems do annelids and mollusks have?nephridia
4 components of the urinary systemkidneys, ureters, bladder, and urethra
hollow muscular chamber that collects and stores urinethe bladder
internal sphinctermuscle of the bladder that is the junction of the bladder and the urethra. it opens automaically
external sphinctermuscle of the bladder that is slightly below the internal sphincter and is under voluntary control
capacity of the bladder500mL
3 parts of the kidneyrenal cortex, renal medulla, and renal pelvis
where do the kidneys produce concentrated urinerenal medulla
where in the kidneys is urine collected and sent into the ureter?renal pelvis
nephronsmicroscopic filters in the kidney that are packed together in the renal cortex with a portion extending into the renal medulla
how many nephrons does a human have1 million
2 parts of the nephronthe gomerulus and the long twisted tubule
4 major sections of nephron tubulesbowman's capsule, proximial tubule, loop of henle, and the distal tubule
what is the only part of the nephron that is in the renal cortexthe loop of henle

Section 2

Question Answer
excretion definitionthe removal of unwanted substances from the body including nitrogen containing compounds from protein (amino acids) and from DNA and RNA (nucleic acids)
symbol for amino groups-NH2
symbol for ammoniaNH3
homeostasis defthe relative constant internal environment
what does homeostasis do in the urinary systemregulates the composition of the blood and extracellular fluid
the formation of urea in protein synthesisproteins-->amino acid-->amino groups-->ammonia-> urea in liver (or uric acid elsewhere)
what are the functions of the R and carboxyl groups after ammonia is metabolized from the amino groupused for cellular respiration, glucose synthesis, and lipid synthesis
what is the biggest killer of aquarium fish?ammonia posioning. ammonium (NH4+) under acidic conditions. Ammonia (NH3) under basic condtions
what are protonephridia?filters interstitial fluid by collecting and excreting primarily excess water. found in flatworms
what are malpighian tubules?filters nemolymph and produces concentrated urine. Found in insects.
what are nephridia?filters interstitial fluid, reclaims nutrients and urine is collected in a bladder then exits. found in annelids and mollusks
3 functions of the mammalian urinary systemfilter small molecules and ions out of the blood, return essential ions and nutrients to the blood, and collect and excrete excess substances and cellular wastes
how does blood enter the kidneys?through the renal arteries
where is blood filtered?in the kidneys
where does blood leave the kidneys?through the renal veins
where does urine leave the kidneys through?the ureters
where does the urine go after the ureter?the bladder
where does urine exit the body through?the urethra
what is the junction of the bladder and the urethra?the internal sphincter
what is the area below the internal sphincterthe external sphincter
the solid outer layer of the kidneythe renal cortex
the middle layer of the kidney where kidneys produce concentrated urinethe renal medulla
the inner most branched funnel like chamber that collects urine and conducts it into ureterthe renal pelvis
function of the gomeruluswhere fluid is filtered out of the blood through porous capillary walls
function of the long twisted tubulewhere urine formation occurs
function of the bowmans capsulecup-like chamber surrounding the glomerulus that receives fluid filtered out of the blood from the glomerulus
function of the proximial tubuledelivers fluid from Bowman's capsule to the loop of henle
function of the loop of henleextends down into the renal medulla and delivers fluid from the proximial tubule to the distal tubule
function of the distal tubulein renal cortex. delivers fluid from the loop on henle to the collecting duct
function of the collecting ductcollects fluid from many nephrons and deposits it in the renal pelvis for excretion
what creates a high salt concentration in the renal medullathe loop of henele

Section 3

Question Answer
how is the composition of the blood and extracellular fluid regulated by homeostasisfilters, adjusts water content, adjusts blood pH so the blood does not get too acidic it removes H+, and it adjusts the osmolarity of the blood
what happens to the rest of the amino group when ammonia is removed in metabolismcarboxyl and R groups are metabolized for cellular respiration (energy production), glucose synthesis and lipid synthesis
6 steps of formation of urea from protein dehydrationeat food and protein digested, amino acids carried into blood, amino groups (-NH2) are metabolized to ammonia (NH3) which is carried in blood to the liver, liver converts ammonia to urea, urea is carried to the kidneys and then urea goes into urine in the kidney nephrons
what is filtered out of the blood?small molecules and ions
what is returned to the blood?essential ions and nutrients
can you live with one kidney?yes
how is urine transported from the ureter to the bladder?through contractions of the ureter
6 steps of the urinary systemrenal arteries-->kidneys-->renal veins-->ureters-->bladder-->urethra
is the internal sphincter under voluntay or involunary controlinvoluntary
is the external sphincter under voluntary or involuntary controlvoluntary (until the bladder is completely full)
the layers in order of the kidney from outermost to innermostrenal cortex-->renal medulla-->renal pelvis
where is fluid filtered out of the blood through porous capillary wallsglomerulus
where urine formation occursthe long twisted tubule
is the collecting duct part of the nephronno
where is the glomerulus locatedrenal cortex*
where is the proximial tubule locatedrenal cortex*
where is the distal tubule locatedrenal cortex*
where is the loop of henle locatedrenal medulla
3 stages in which urine is produced by the nephronsfiltration, tubular reabsoption, and tubular secretion
why does the loop of henele create a high salt concentration in the renal medulla?helps kidney retain water which is reabsorbed by capillaries as water flows out of tubules (by osmosis and by aquaporins) and to create a concentrated urine excretion

Section 4

Question Answer
2 sphincter muscles of the bladderinternal sphincter and external sphincter
what is the function of the renal cortexit is the outermost layer of the kidney
what is the function of the renal medullait is the middle layer of the kidney where kidneys produce concentrated urine
what is the function of the renal pelvisit is the innermost layer of the kidney where urine is collected and conducts into ureter
parts in order of the nephron(from glomerulus not part of nephron tubules)-->Bowman's capsule-->proximial tubule-->loop of Henle--->distal tubule-->collecting duct (not part of nephron)
blood osmolaritya measure of the concentration of ions and other solutes diluted in the blood
how much water is filtered per minute in the blood1/2 cup of water and solutes
what would happen if kidneys couldn't reabsorb water after it was filtered outa lot more water would have to be consumed per day
what is the function of nephrons in the kidneysfilter blood and produce urine
how big of a blood supply do nephrons havea big blood supply to support the role maintaining homeostasis
how much of the blood from each heartbeat is filtered by the kidneys1/4 of the blood
blood flow in kidneys in orderblood enters via renal artery-->arterioles-->glomerulus capillary network-->outgoing arteriole--->more capillaries around the tubules-->venule-->renal vein-->inferior vena cava
how is urine formed and concentratedas urine forms, small organic nutrients are filtered out and then returned to the blood by reabsorption
filtrationglomerulus filters water and most small dissolved molecules out of the blood
tubular reabsorptionwater and nutrients are filtered out of the blood by nephrons, leaving wastes (urea) behind
tubular secretionwastes and excess ions remaining in the blood are secreted into the nephron
how are small dissolved molecules and ions forced through the walls of the glomerular capillariesby a pressure gradient (high-->low). the blood pressure in the glomelar cavities is very high and the capillary walls are very porous. therefore a portion of the blood fluid is forced out into the kidney
tubular reabsorption takes place mostly in the proximial tubule but also occurs in the distal tubule
what happens to the water during tubular reabsorptionmost of the water that was filtered out from the blood in the glomerulus is reabsorbed by the blood
what remains in the tubule after tubular reabsorptionurea (waste)
wastes examplesammonia, drugs, food additives, pesticides, toxic substances (nicotine)
urine formation occurs byactive transport
when is urine formed?when the filtrate leaves the distal tubule
the loop of henele generates a __________ in interstitial fluid of renal medullaa high salt concentration

Section 5

Question Answer
five functions of kidneys help regulate water and ion content of blood, maintain proper pH of blood, secrete hormones that help regulate blood pressure and oxygen levels, and eliminates cellular waste products (urea)
diuretichigh urine production
antidiureticlow urine production
dehydrationthe pituitary gland secretes ADH into blood which stimulates insertion of aquaporins into collecting duct to reabsorb more water
high antidiuretic hormone (water absorption)high water absorption
increased blood osmorality leads to the hypothalmus detects this and signals the pituitary gland to secrete ADH into the bloodstream which increases the permeability of the distal tubule and the collecting duct which allows more water to be reabsorbed into the blood. the water is retained in the body and concentrated urine is produced
why do you pee so much when you drink?alcohol inhibits ADH release so there is no insertion of aquaporins into the collecting duct so there is no water reabsorption. this can cause dehydration
low antiduretic hormone (water absorption)low water absorption
3 causes of kidney failurediabetes and high blood pressure damage te glomeular capillaries, infection, and overdoses on pain meds
kidney stonescrystalization of minerals in the kidneys
hemodialysis for kidney failurepatients blood is diverted from the body and pumped through a machines with thin membranes to filter the blood. The machine allows small molecules to pass through and prevents the passage of blood cells and large proteins
kangaroo rat kidneyshave very salty urine and never have to drink water because they have long loops of Henle
mammals adapted to dry climates havelong loops of Henle
long lupes of Henle allow a higher salt concentration to be produced in the tubules and allows water to be reabsorbed from the urine
fish do not havenephrons
what is tricky in fish osmoregulation- the maintnence of a homeostasis balance of internal water and salt concentrations
freshwater fishwant to conserve salt and remove water (salts actively pumped in)
saltwater fishwant to conserve water and remove salts (salts actively pumped out)