Rat Dissection

Rat Classification

• The Rat, Rattus norvegicus albinus, belongs to the Kingdom Animalia, phylum Chordata, Class mammaila, Order Rodentia, genus Rattus, and species norvegicus.

Orientation

External Anatomy

Sex?• On female rats, just posterior to the

last pair of teats, you will find the urinary aperture and behind that the vaginal orifice which is in a small depression called the vulva.

• On males, you will find a large pair of scrotal sacs which contain testes. Just anterior to the scrotal sacs is the prepuce, which is a bulge of skin surrounding the penis. The end of the penis has a urogenital orifice, where both urine and sperm exit.

Can you tell which one is the male?

Muscles

Body Cavities

Thoracic Cavity

Abdominal Cavity

What organs are found in this cavity?

What organs are found in this cavity?

What muscle would be indicated by the red line?

Thoracic CavityWhat are the names and functions of all the structures indicated by red arrows?

12

3

456

7

Circulatory System in the Thoracic Cavity

Thoracic CavityWhat gland covers the heart and what is it’s function?

How many lobes total… How many on the right and on the left?

What is this tube and what is it’s function?

Throat/Neck Region

1 23

4

What are the structures indicated by the red arrows and what are their functions?... Hint… Number three is a gland that controls metabolism and is under control by the anterior pituitary.

Abdominal Cavity• What organ is

this?• How many lobes

does it have? • What digestive

functions does it have?

• How does it help control blood glucose levels?

• How does it function in the excretory system?

• What does it do for the blood?

Abdominal Cavity• What organ is

indicated by pin #1?

• How does it control blood glucose levels?

• What digestive functions does it have?

• What organ is indicated by pin #3?

• What is it’s function?

• Pin #4 is in the duodenum… Why is this an important location?

Abdominal CavityCan you name the structures?

Male and Female Urogenital/Reproductive Systems

Which is male and which is female?

Male or Female?

1

2

3

4

5

6

What are the structures labeled with red arrows? What are their functions?

Male or Female?How is the uterus of the rat different from a humans?

What structures are indicated by 3 through 7?