LABORATORY EXERCISE 58

CAT DISSECTION: URINARY SYSTEM

Laboratory Report Answers

1.     In the human, the kidneys are located between the levels of the twelfth thoracic and the third lumbar vertebrae; in the cat, the kidneys are found at the level of the third to the fifth lumbar vertebrae. In the human, the left kidney is usually higher than the right one; in the cat, the right kidney is usually somewhat anterior to the left one. In both cases, the kidneys are retroperitoneal.

2.     In the human, the adrenal glands are located on the superior ends of the kidneys; in the cat, the adrenal glands are located anteriorly and medially to the kidneys.

3.     In the cat, the kidneys, ureters, and urinary bladder are retroperitoneal.

4.     The wall of the urinary bladder is relatively thick, tough, and somewhat elastic. Its inner surface is irregular.

5.     In the human kidney, there are about twelve renal pyramids that communicate with the renal pelvis by calyces. Each calyx bears one or more papillae. In the cat kidney, there is a single pyramid and one papilla.

LABORATORY EXERCISE 59

CAT DISSECTION: REPRODUCTIVE SYSTEMS

Laboratory Report Answers

PART A

1.     The cat uterine tubes are small, coiled tubes near the ovaries that travel relatively short distances to join the uterine horns.  The human uterine tubes are much larger and longer, traveling from the region of the ovaries to the uterine body.

2.     The human uterus contains a single chamber in which the offspring develop. The cat uterus is Y-shaped with branches, forming right and left uterine horns.

3.     The uterine horns of the cat provide room for many offspring to develop at one time.

4.     In the cat, the vagina and urethra open into a common urogenital sinus; in the human each of these organs has a separate opening to the outside.

PART B

1.     The glans penis of the cat has small spines on its surface, whereas that of the human does not.

2.     In the cat, the prostate gland is relatively small and is located some distance from the urinary bladder (it does not surround the urethra). In the human, the prostate gland is relatively larger and surrounds the urethra near the base of the bladder.

3.     The seminal vesicles are lacking in the cat.

4.     The prepuce of the cat encloses the entire penis for protection. In the human, the prepuce or foreskin is vestigial and only covers the glans penis. A circumcision is commonly performed on humans to remove the prepuce for sanitation and other reasons.