FROG DISSECTION LAB

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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.
mouth
small intestine
esophagus
gall bladder
stomach
pancreas
liver
large 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.
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