Unit 4- Chapter 19 Physiology
Urine is carried to the urinary bladder by
the ureters.
Urine is carried to the external environment by the
urethra.
After it is formed, urine is temporarily stored in the
urinary bladder
The characteristic yellow color of urine is attributed to the presence of
urobilinogen
All of the following will normally be found in the filtrate EXCEPT
urobilinogen erythrocytes*** potassium glucose
Measurements in a nephron reveal a glomerular hydraulic pressure of 69 mm Hg, and a fluid pressure in the Bowman's capsule of 15 mm Hg. Assuming that the plasma osmotic pressure is 30 mm Hg, and that essentially no plasma proteins are filtered by the glomerulus, what is the net glomerular filtration pressure in this case?
24 mm Hg
Calculate the net filtration pressure if capillary hydrostatic pressure is 60 mm Hg, capillary osmotic pressure is 25 mm Hg, and capsular hydrostatic pressure is 10 mm Hg.
25 mm Hg
Which of the following correctly indicates the direction of the different forces causing filtration in the renal corpuscle (of fluid flow into or out of Bowman's capsule from the glomerular capillaries)?
Blood hydrostatic pressure - (out), blood colloid osmotic pressure - (in), hydrostatic fluid pressure of the Bowman's capsule - (in)
A glomerulus is
a "knot" of capillaries that lies within the Bowman's capsule.
In a normal kidney, which of the following conditions would cause an increase in the glomerular filtration rate (GFR)?
a decrease in the concentration of plasma proteins in the blood
movement from the glomerulus to the nephron lumen
filtration
The amount of filtrate entering the proximal tubules of the kidneys each minute is the ________ rate.
glomerular filtration
Glomerular filtration rate is determined by the net filtration pressure and the filtration coefficient. Which two factors determine the filtration coefficient?
glomerular surface area and the permeability of the filtration barrier
Where does all filtration take place in the kidneys?
glomerulus
What is the primary driving force (pressure) that produces glomerular filtration?
hydrostatic pressure of blood (blood pressure)
If the osmotic pressure in the glomerular capillaries increased from 28 mm Hg to 35 mm Hg, would net filtration increase or decrease?
net filtration would decrease
The hairpin-shaped segment of the nephron is the
loop of Henle.
The functional unit of the kidney is the ________.
nephron
If blood flow through the afferent arterioles increases,
stretch reflexes trigger vasoconstriction to reduce the flow.
Neural control of GFR is mediated by ________ that innervate ________ receptors on vascular smooth muscle causing ________.
sympathetic neurons, alpha, vasoconstriction
Approximately how much plasma moves through the kidneys of an adult during a 24-hour period?
180 L
Place the following blood vessels that carry blood to and within the kidney in the order in which blood passes through them. 1. afferent arteriole 2. efferent arteriole 3. glomerulus 4. peritubular capillary
1, 3, 2, 4
Ions directly regulated by the kidney include all EXCEPT which of the following?
HCO3- Na+ OH-*** K+ Ca2+
What causes the internal urethral sphincter to open?
Increasing urine pressure due to contraction of the full bladder
Why is inulin administration an effective way of measuring renal clearance rates?
Inulin is neither secreted nor reabsorbed.
Why is the regulation of extracellular fluid osmolarity so important?
It strongly influences cell volume.
Which combination of changes would increase the glomerular filtration rate (GFR) the most?
Vasodilation of the afferent arteriole and vasoconstriction of the efferent arteriole
The force for glomerular filtration is the
blood pressure in the glomerular capillaries.
The portion of the nephron that attaches to the collecting duct is the
distal tubule.
An obstruction in a glomerulus would affect the flow of blood into the
efferent arteriole.
Which equation correctly describes the relationship between excretion, filtration, reabsorption, and secretion?
excretion = filtration - reabsorption + secretion
Which of the following substances is not normally found in filtrate?
ions, such as sodium and potassium blood cells and large particles*** nitrogenous waste particles, such as urea water and small solutes
Urine is produced by the
kidney
Approximately what percent of the total filtered volume is excreted as urine each day?
less than 1%
The segment of the nephron between the proximal and distal tubules that loops down into the medulla of the kidney and returns back to the cortex is called the ________.
loop of Henle
In normal kidneys, blood cells and plasma proteins are
not filtered
Which chemical can stimulate ventilation by binding both peripheral and central chemoreceptors?
plasma CO2
Which unique epithelial cells of Bowman's capsule are involved in filtration?
podocytes
Which substance would be found in higher concentration if the membrane were damaged?
protein
Most reabsorption of fluid from the filtrate back into the blood occurs from the ________.
proximal convoluted tubule
movement from the nephron lumen to the blood
reabsorption
The primary function of the proximal tubule is
reabsorption of ions, organic molecules, and water.
The kidneys function to produce hormones, excrete wastes, regulate blood pressure, and maintain ion balance. Which of the following is another function of the kidneys?
regulate osmolarity
Functions of the kidneys include all but one of the following. Identify the exception.
regulation of extracellular fluid volume regulation of blood protein levels*** maintenance of ion balance in body fluids regulation of blood osmolarity homeostatic regulation of blood pH
The ________ branch off the ________ and supply blood to the kidneys.
renal arteries, abdominal aorta
The ________ carries blood from the kidneys back to the ________.
renal vein, inferior vena cava
Contents in the peritubular capillaries are actively transported into proximal and distal convoluted tubules in a process known as:
secretion
Which word means to selectively move molecules from the blood and add them to the tubule lumen?
secretion
movement from the peritubular capillaries to the nephron lumen
secretion