Excretory System

Question 1

Osmoregulation

Answer 1

The way in which the body balances its water content

Question 2

Nephridia

Answer 2

Found in each body segment of a worm; drains fluid from the segment ahead of it; lined with capillaries; as fluids pass through the nephridia, materials are exchanged between the two;

Question 3

Malphigian tubules

Answer 3

Tubular structures within insects that collect nitrogenous waste from the blood and release it into the digestive tract, where it joins digestive waste (due to insect’s open circulatory system)

Question 4

Human excretory system

Answer 4

Includes kidneys, ureters, bladder, urethra, hormones involved in water balance, and lungs (CO2 is a metabolic waste product)

Question 5

Renal artery

Answer 5

Brings blood towards the kidney

Question 6

Renal vein

Answer 6

Brings blood away from the kidney

Question 7

Glomerulus

Answer 7

Entrance to the nephron

Question 8

Nephron

Answer 8

Filtration unit of the kidney; over 1 million nephrons in each kidney

Question 9

Nephron filtrate movement

Answer 9

Glomerulus > proximal tubule > Loop of Henle > distal tube > collecting duct

Question 10

Bowman’s capsule

Answer 10

Surrounds the glomerulus; squeezes capillaries to force fluids out

Question 11

Urea

Answer 11

The waste in the blood stream

Question 12

Ureter

Answer 12

Tube from kidney to urinary bladder

Question 13

Urethra

Answer 13

Tube out of bladder, out of the body

Question 14

Main components of filtrate

Answer 14

Sugar, salt, water, urea, amino acids, and various ions; resembles blood plasma (minus lack of large proteins)

Question 15

Urine

Answer 15

Made of urea, excess salt, and excess water; no sugar

Question 16

ADH

Answer 16

Antidiuretic hormone; released by posterior pituitary gland; with ADH, proximal tubule is more permeable to water and more water is reabsorbed by osmosis; without ADH, proximal tubule is impermeable to water

Question 17

Angiotensin

Answer 17

Secreted by liver; when blood pressure falls, tells the brain to release ADH and makes the adrenal glands release a hormone called aldosterone

Question 18

Aldosterone

Answer 18

Decreases water and Na+ excretion and blood pressure goes UP because of retained water

Question 19

Types of nitrogenous waste

Answer 19

Ammonia (in aquatic organisms), urea (mammals, amphibians, some fish like sharks), and uric acid (birds, reptiles, and insects); ammonia requires a lot of dilution with water, urea less so, and uric acid virtually none