We will break up this
dissection into 6 parts; External Features, Respiratory system, Digestive
System, Circulatory System, Excretory System, and Reproductive system.
You are responsible to
know the functions and location of the organs and features gone over in this
This lab will be split
up into 5 days
Day 1, External features
and Respiratory system
Day 2, Digestive System
Day 3, Circulatory
Day 4, Excretory and
Day 5, Reproductive
System and make up
You will have a particle
exam on the Monday after the dissection
Use your razor blade to
cut along dotted line, CAREFULL!
Dont cut to deep but
deep enough to get through muscles
You are going to have to
break the ribs to get into the upper Thoracic cavity
External Features/ Respiratory
Functions of external an respiratory systems
Diaphragm- This is a muscular sheet that separates cavities and
its action is to draws air into the lungs.
Nostril, Eyes Sensory organs
Claws defense, eating, grasping, climbing
Mouth and Nostril Intake for air
Larynx produce sound for communication
Trachea Tube to bring air into lungs
Bronchus Branches into lungs
Lung Exchange oxygen form air into blood an expel carbon
Diaphragm - Muscle that
helps fill lung with air
Gall Bladder (rat
doesnt have one)
Functions of Digestive system
Mouth Break down food both mechanically and physically
Epiglottis Barrier to prevent food from entering the lungs
Esophagus- Muscular tube to carry food to stomach
Pancreas- This organ gives digestive enzymes to the small
Stomach- This is a curved, bag-like structure under the left
side of the liver. Helps break down food both chemically and physically
Small Intestine- This is a long, coiled tube that leaves the stomach.
Absorption and digestion of food takes place here.
Mesenteries- These are translucent membranes attached to and
holding the internal organs in place. Blood vessels travel along them and fat
bodies are often present.
Large intestine Long tube that collects waste
Rectum Last stop, This is the muscular organ, which removes
water from waste and helps expel the waste from the body.
Cecum - contains
bacteria that help the rat to break down cellulose
Spleen- This organ stores red blood cells and manufactures
white blood cells.
Left and Right Atrium
Left and Right Ventricle
Functions of Circulatory System
Heart pump that supplies the body with blood
Pericardium- protects the heart
Vena Cava- supplies used blood to Right atrium
Aorta Main artery out of left ventricle
Left Atrium and
Ventricle chambers that pump blood
Right Atrium and
Ventricle chambers that pump blood
to the lungs
Vein (back to heart), pathway for used blood
Artery (away from heart), pathway for oxygen rich
blood(except pulmonary arteries)
Functions of Excretory System
Liver- This is a large, brown organ takes up most of the
anterior of the cavity. It consists of four lobes, and is used for removing
toxins from the blood.
Kidney- This organ filters wastes from the blood.
Ureter- This is a tube that carries the wastes away from the
Urinary Bladder- This organ is a sack which temporarily stores urine.
Urethra- This organ is the tube that passes out of the
bladder to the outside of the body.
Female Reproductive System
Ovary- An egg producing gonad of the female.
(uterus)- female reproductive
structure where eggs are stored or fertilixed or where development of the youn
Vagina- muscle tube for receiving sperm.
Male Reproductive System
Functions of Male Reproductive System
gamete producing organ
Deferense tube that carries sperm
organ that deposits sperm in the female reproductive system