The thyroid gland is darker and lies between the posterior ends of the two lobes of the thymus gland. Label these on your hand-in. Find the scrotal sacs at the posterior end of the pig between the legs , testis are located in each sac. Fetal pigs not used in classroom dissections are often used in fertilizer or simply discarded. What does the letter C refer to in the figure of the internal anatomy of the fetal pig? Remove this sac to expose the heart. If a structure is anterior to another, then it is closer to the head.
Fetal pigs receive their nourishment from their mother through the umbilical cord. Start the cut with a , then continue it with. The stomach may not be empty because fetal pigs swallow amniotic fluid. Observe the toes of the pig. Transports deoxygenated blood to lungs. Use the probe to peel away muscle tissue until the thymus gland on each side of the trachea is exposed. The spleen stores blood and is not part of the digestive system.
We have revised this site to improve the learning experience and accessibility. A 1980 study found that exposure to formaldehyde could possibly cause nasal cancer in rats, leading to research on whether this was possible in humans or not. The Epiglottis is a flap of skin that makes sure no food gets into the Respiratory tract. The structures visible on the heart are the two atria 12,13 , the ventricle 14 which has two chambers not visible from the outside. Many other factors, including depth of placental folds, are also responsible for these interactions. In the female these structures connect to the mammary glands.
The pharynx is the space in the posterior portion of the mouth that both food and air pass through. Although increasing placental fold width does increase the interaction between fetus and mother, nutrient exchange is not most efficient in smaller fetal pigs, as would be expected. Fetal Pig Dissection Fetal Pig Dissection Background: Mammals are vertebrates having hair on their body and mammary glands to nourish their young. The reason as to why the left ventricle contains more muscle than the right ventricle is because the left ventricle must be strong enough to pump the blood throughout the body while the right ventricle only needs to pump the blood to the nearby lungs. The appendix in humans is the evolutionary remains of a larger cecum in human ancestors. The common carotid 4 , which will branch into the left 7 and right carotid arteries 8.
In addition, they are relatively large with well-developed organs that are easily visible. The second branch is the left subclavian artery which goes to the left front leg. The larynx allows the pig to produce sounds - grunts and oinks. Within this site, you can navigate to any chapter from the links at the left. Students will be able to identify and explain the structure and function of the internal and external anatomy of the fetal pig. This allows blood to pass directly from the right to left atrium. Pancreatic juice, made by the pancreas, and bile, made by the liver and stored in the gall bladder, are add to food here to continue digestion.
Piglets can have 28 teeth total and adult pigs can have 44 teeth total. Instead, it gains much needed nutrition from the mother pig via the umbilical cord. Locating the left atrium is also visible within the eye. The caecum has no known function in the pig. You should now be able to peel open the left and right flaps of the ventral body wall like a book. Above the diaphragm, center of chest, is the heart.
Materials: preserved fetal pig, dissecting pan, dissecting kit, dissecting pins, string, plastic bag, metric ruler, paper towels Pre-lab: Before observing internal or external structures of the fetal pig, use your dissection manual, textbook, and dissection notebook to answer the pre-lab questions on the fetal pig. The abdominal cavity is now exposed. The vagina will actually will appear as a continuation of the uterus. As long as the pork industry exists, fetal pigs will be relatively abundant, making them the prime choice for classroom dissections. Pancreatic juice flows through pancreatic ducts to the duodenum. Obtain a piece of masking tape and label your bag with your names.
View the inside of the stomach by slicing it open lengthwise. The amount of floor space has been shown to impact the time it takes gilts to reach puberty. Use your pig and also a pig of the opposite sex to identify the structures in the photographs below. Also locate the anterior and posterior ends. Leave stubs of the vessels on the heart and identify them. The aorta will curve back and then branch in two spots - the right brachiocephalic 3 and the left subclavian 5 6. In the figure of the internal anatomy of the fetal pig, what letter refers to the liver? If you have a male pig, cutting off-center ensures that you do not cut the penis, which is incompletely formed in the fetal pig and appears as a thickened tube within the skin of the lower abdominopelvic area.