Lesson 2- Excretory System

Question 1

kidney function

Answer 1

filter waste from blood (urea, uric acid), balance blood ph, and maintain water balance

Question 2

kidney structure

Answer 2

cortex, medulla, and renal pelvis. within the cortex and medulla are structures called nephrons

Question 3

nephron structure

Answer 3

afferent arteriole, efferent arteriole, glomerulus, bowman’s capsule, proximal tube, loop of henle, distal tube, collecting duct, peritubular capillaries

Question 4

filtration

Answer 4

blood goes through afferent arteriole into the glomerulus and diffuses into bowman’s capsule to move to the proximal tube. fluid (water, ions), small nutrients (glucose, amino acids), and urea (waste) can only be filtrated, not bigger molecules like rbc. filtered blood leaves through efferent arteriole and wraps around nephron in peritubular capillaries.

Question 5

reabsorption

Answer 5

occurs in peritubular capillaries, proximal tube, decedning tube of henle, and distal tubes. ion pumps transport k, an, cl from filtrate to the fluid, active transport proteins (embedded) reabsorb amino acids, glucose, and other nutrients out of the filtrate, aquaporins allow water to flow out with osmosis.

Question 6

secretion

Answer 6

occurs in peritubular capillaries, proximal and distal tubes, and collecting ducts. proximal tube secretes h, poisons, and ammonia (from liver) from blood, along with k and h at disral tubes. depending on body’s acidity h ions might be excreted at collecting ducts as well.