FROG DISSECTION LAB
Name: ______
Background
The acquisition of sugar is mandatory for all heterotrophic organisms. Being heterotrophic, animals require means of acquiring, digesting, and delivering sugar to each of their cell for cellular respiration. In the cell, the energy in the carbon bonds of the sugar is used in the production of ATP, the ultimate energy source of animal cells. In this lab, you will become familiar with the structure and function of the digestive system in general, as well as come to understand how the digestive system processes large carbohydrates, lipids, and proteins, making them small enough to be transported through the cells lining our intestine into the surrounding circulatory system.
Objective
1. You should be familiar with the general digestive anatomy and physiology of an highly evolved animal having a complete digestive system.
2. You should know how and where the digestive system breaks down carbohydrates, lipids, and proteins so that they may be absorbed into the circulatory system.
Materials
Leopard Frog
Dissection Tray
scissors
scalpel
probes
forceps or tweezers
Procedure
1. Acquire a frog dissection specimen and other appropriate materials listed above.
2. Lay the frog on its back in the middle of the dissection tray. Using a scalpel and/or scissors make a vertical incision through the skin, starting in the genital area and ending at the breast. Further, make a lateral incision across the breast. Peel back the skin.
3. After viewing the muscles exposed, make similar incisions using the scalpel and/or scissors to expose the body cavity. Be careful not to damage internal organs when complete this step. If necessary use scissors to cut through the humorous arm bone so that the arms will lie back out of the way.
4. Using the figure of the human digestive system on page 602, try to identify the parts of the amphibians digestive anatomy. Answer the questions that follow.
Questions
1. Draw and label the digestive anatomy of the frog. Make sure to label the following digestive anatomy.
mouthesophagusstomachliver
small intestinegall bladderpancreaslarge intestine
2. Name and describe the five categories of tasks that the digestive system carries out.
3. Describe the basic function of each of the digestive anatomy listed below.
mouth
esophagus
small intestine
liver
gallbladder
pancreas
large intestine
4. Respiration requires the acquisition of glucose. Assuming that you or your frog has eaten a meal contain large amounts of polysccharides (cellulose or glycogen), identify and describe the three steps that would take place to ‘chemical digest’ a polysaccharide into a monosaccharide that could then be absorbed into your circulatory system. Make sure to name the specific enzymes involved, the source of the enzyme, the location of the enzyme production, as well as the substrate and break down product.
5. Your body requires the acquisition of lipids in the diet. Assuming that you or your frog has eaten a meal contain large amounts of lipids, identify and describe the steps that would take place to ‘chemical digest’ a lipid into a constituent parts that could then be absorbed into your circulatory system. Make sure to name the specific enzymes involved, the source of the enzyme, the location of the enzyme production, as well as the substrate and break down product. Finally, identify the general importance of lipid in the diet.
6. Your body requires the acquisition of proteins in the diet. Assuming that you or your frog has eaten a meal contain large amounts of protein, identify and describe the steps that would take place to ‘chemical digest’ a protein into a constituent parts that could then be absorbed into your circulatory system. Make sure to name the specific enzymes involved, the source of the enzyme, the location of the enzyme production, as well as the substrate and break down product. Finally, identify the general importance of protein in the diet.