Homeostasis 9.5b Flashcards
Glomerular Filtration
moves water and solutes except proteins from the blood plasma to the nephron
Tubular Reabsorption
removes useful substances such as sodium from the filtrate and returns it to the blood
Tubular Secretion
moves additional wastes and excess substances from the blood into the filtrate
Water Reabsorption
water is returned to the blood
4 processes crucial to the formation of Urine
glomerular Filtration, tubular reabsorption, tubular secretion, water reabsorption
Proximal Tubule
Reabsorption.
Active: sodium, potassium, glucose, amino acids
Passive: Chloride ions
Osmosis: Water
Descending Loop of Henle
Passive reabsorption of water. The walls are permeable to water and only slightly permeable to ions. Water goes back into the capillaries increasing the sodium concentration in the filtrate.
Thin Portion of Ascending Loop of Henle
Permeability changes so it is now impermeable to water and slightly permeable to solutes. Sodium ions passively diffuse into the blood.
Thick Portion of the Ascending Loop of Henle
Sodium ions are moved out of the filtrate into the blood by active transport
Active sodium transport Consequences
replenishes salty environment
removal of sodium ions makes the filtrate less concentrated
Distal Tubule
active reabsorption of sodium ions
passive reabsorption of negative ions
potassium ions, hydrogen ions, and medications are secreted.
reabsorption and secretion are controlled by hormones
Reabsorption of water in the collecting duct causes the filtrate to become ___ times as concentrated and it is now ______
4, urine
concentration of ions along the collecting duct ______ as it goes down the medulla causing the passive reabsorption of ______
increases, water
if blood plasma is too concentrated, the permeability of water is ________
increased to conserve water
Which substances were completely reabsorbed into the plasma?
glucose, amino acids, proteins
