What is the final result of the 3 functions of a nephron:
1) Regulate volume and composition of blood plasma by removal of water and dissolved substances
2) Help regulate blood pH
3) Remove toxic waste from blood
Formation of urine
A process forcing some of the water and dissolved substances in blood and plasma from the glomerulus into Bowman's capsule.
Which of the two arterioles has the larger diameter?
What effect does this have on the pressure?
Higher pressure (increase)
What is unique about the permeability of the glomerulus?
What are the two materials not allowed to pass into Bowman's capsule from the glomerulus?
Plasma proteins and blood cells
The rate of filtration is directly proportional to the blood pressure of the __________.
Fluid entering the Bowman's capsule:
What is the rate of filtration per hour?
What is the rate of filtration per 24 hours?
180 L (45gal)/ hr
What effect does low systemic blood pressure have on the rate of filtration?
At what level of systemic blood pressure will filtration stop?
Is urine formed if there is no filtration?
When is the juxtaglomerular apperatus functional?
Low systemic blood pressure
Explain how angiotensin elevates the systemic blood pressure:
In terms of arterioles, explain how the glomerular blood pressure can be elevated:
Angiotensin II constricts effferent arterioles raising glomerular blood pressure. It also increases filtration.
The movement of molecules out of the tubules nad into the peritubular blood:
The movement of molecules out of the peritubular blood and into the tubules:
What fractional part of the filtrate passing into Bowman's capsule will be reabsorbed before reaching the end of the proximal tubule?
More than 2/3
Why is reabsorption a selective process?
Because needed materials are conserved. Excess and waste are exerted in urine
Where is the site of most tubular reabsorption?
Proximal convoluted tubule
How many liters of urine are produced per day?
What condition exists when too much urine is secreted?
What is the condition of blood in the urine?
What is the condition of no urine secretion?
Painful urine excretion:
Ascant amount of urine excreted:
What per cent of the water entering Bowman's capsule will be reabsorbed?
Why is glucose and amino acids not found in the urine normally?
Because all glucose and amino acids are reabsorbed
Compare active and passive transport: discuss types of energy involved; concentration gradient; and carrier molecules:
Active transport- moves from low concentration to high concentration; requires ATP for energy and carrier molecules
Passive transport- moves from high concentration to low concentration; does not require ATP or carrier molecules
How does the reabsorption of sodium and potassium ions differ in the proximal tubules and descending loop of Henle?
By what process are glucose, amino acids, and organic acids reabsorbed?
Passive transport depends on what three factors?
Diffusion, Osmosis, Electomechanical movement
How does osmosis differ from diffusion?
Osmosis only diffuses water across a selectively permeable membrane
________per cent of the water is reabsobed in the proximal tubule, and ________per cent is reabsorbed in the loop of Henle and the distal tubule.
Which process allows the body to rid itself of excess substances and hel control blood pH?
What effect does increased concentration of ions in the peritubular capillary have on the osmotic pressure of blood?
Increases osmotic pressure
By what two processes can secretion occur?
Passive and avtive transport
Which ion is actively secreted into the proximal tubule and also actively secreted into the distal tubule?
How are potassium ions secreted?
Passibely secreted into distal tubule
Where does the renin-angiotensin mechanism originate?
What two structures meet at the junction in the juxtaglomerular apparatus?
Afferent arterioles and distal tubule
What stimulus is necessary for the contraction of smooth muscle?
Under what condition of systemic blood pressure will the afferent arterioles be dilated? ________ constricted? ________
Decreased systemic blood pressure
Increased systemic blood pressure
What effect does increased solute have on the secretion of urine?
Increased solute leads to increase in urine
Hormone secreted by muscle fibers in the atrial wall of the heart: ________; effect on urine volume: ________
Atrial Natriuretic Peptide
Hormone secreted by the posterior pituitary gland: ________ effect on water loss: ________ effect on sodium ions: ________
Increase sodium absorption
Hormone produced by the adrenal cortex: ________ its effects on urine volume: ________
What is glycosuria?
What health condition exists with glycosuria?
Glucose in the urine.
Hollow muscular organ providing temporary storage for urine:
What prevents urine in the kidney bladder from backing up into the ureter?
A flap like fold of mucous membrane covers opening of ureters
Give the beginning and end of the ureter:
Begins with renal pelvis and ends with lower lateral margin of urinary bladder
Which layer in the wall of the ureter is smooth muscle?
Peristaltic waves are associated with which layer of the ureteral wall?
What is the function of the peristaltic waves?
Transport urine from ureter to bladder
The inner layer of the wall of the ureter is continuous with what?
Renal pelvis, urinary bladder, urethra
What bony structure lies anterior to the urinary bladder?
Using the equation on effective filtration pressure (EFP) what combination of forces move fluids out of the glomerulus?