Question

question 19 (5 points) which of the following correctly orders the steps in liquid waste excretion? a) urethra → urinary bladder → kidneys → ureters b) kidneys → urethra → urinary bladder → ureters c) kidneys → ureters → urinary bladder → urethra d) ureters → kidneys → urinary bladder → urethra question 20 (5 points) which of the following is true of red blood cells? a) they live for only 120 days. b) they live for only about 20 days. c) once created in bone marrow, they circulate for our lifetime. d) they have multiple nuclei.

Explanation:

• For Question 19: The kidneys filter waste to form urine, which travels through ureters to the urinary bladder, and then out of the body through the urethra.
• For Question 20: Red - blood cells are produced in the bone marrow and have a lifespan of about 120 days. They are anucleate (do not have a nucleus).

Answer:

Question 19: C. Kidneys → ureters → urinary bladder → urethra
Question 20: A. They live for only 120 days.