Difference Between A Frog And Dissection

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Chordate Dissection and Anatomy In this lab, a dissection was performed on a mouse, a frog, and a dogfish shark, and the anatomy was observed and noted. The three animals have some similarities and differences. The mouse, frog, and dogfish shark are all similar in that they all have closed circulatory systems. But the three animals have different types of hearts. The mouse has a four chambered heart, the frog has a three chambered heart, and the dogfish shark has a two chambered heart. The respiratory tract in the three animals are all different. The shark has a set of gills which extracts oxygen from the the water that passes over them, the mouse has a set of lungs though which it breathes air, and the frog has lungs to breathe air but is also able to respire through their skin when swimming. The digestive system of the frog and shark follow the same digestive tract: Food enters the mouth, goes down the esophagus, to the stomach, small intestine, large intestine, finally exiting the cloaca in the form of liquid or solid waste. The frog and the shark excrete solid and liquid waste through the same body cavity, the cloaca. For the mouse: food enters the mouth, down the esophagus, to the stomach, small intestine, large intestine, with …show more content…
The excretory system of the mouse is different from the shark and frog because its liquid waste is excreted through the urethra. Also, the shark contains a rectal gland which helps remove sodium chloride(salt) from the sharks body. The sharks kidneys have a different structure then the mouse and frog because they lie flat on …show more content…
First, the weight of each mouse was recorded. Then, the weight of each of their hearts were recorded. The null hypothesis was that there is no correlation between the weight of the mouse compared to the weight of its heart. The rs value for the Spearman's rank-order test was 0.48. The test determined that there is no correlation between the weight of the mouse and the weight of its heart. The test is shown in Table 1 below.
Figure 1. The mouse prior to dissection with external features labeled.
Figure 2. Images of the mouse during dissection with organs and internal features labeled.
Figure 3. The Dogfish shark prior to dissection with external features labeled.
Figure 4. The labeled internal structures of the dissected dogfish shark.

Figure 5. The labeled organs and internal features of the dissected dogfish shark.
Figure 6. The labeled organs, internal, and external features of a dissected dogfish shark.

Figure 7. Images of the frog after dissection with internal organs labeled.
Figure 8. Image of the frog after dissection with internal organs labeled.

Group
Body weight (g)
Body weight rank
Heart weight (g)
Heart weight rank
Rank difference
Rank Difference squared
1
33.24 g

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