Frog Dissection Lab

What We Did

In this lab, we spent one week dissecting, observing and researching the anatomy and functions of a Grass Frog. We look at the internal and external anatomy of the frog. My partner and I dissected the frog, looked at the organs, muscles and tissues, researched their function, and learned their role in each body system.

Body Systems

The body systems we looked at were the skeletal system, the muscular system, the circulatory system, the respiratory system, the digestive system, the reproductive system, the excretory system and the nervous system. All of these systems can be found in the human body, as well.

Phylum and Class

The phylum of a Grass Frog is chordate. The class of a Grass Frog is amphibian.

Characteristics of the Phylum

The characteristics of the phylum chordate are:

• it has a hollow dorsal nerve cord
• it has a notochord (a cartilaginous skeletal rod supporting the body in all embryonic and some adult chordate animals)
• it has Pharyngeal gill slits
• it has a tail that extends beyond the anus (post-anus tail)

Characteristics of the Class

Some characteristics of the amphibian class are:

• they are cold blooded animals, meaning they have no constant body temperature but they take on the temperature of their environment
• they have backbones
• they have moist, scaleless skin that absorbs water and oxygen or permeable skin
• they have unshelled eggs
• they have to be a species of frogs, toads, salamanders and newts
• they have a three chambered heart
• they have webbed feet

Frogs vs Humans: Skeletal System

Frogs and Humans, obviously, look different, and a big part of this difference is the difference between the skeletal systems. One big difference come in the hind legs. Humans put the majority of our weight on our legs, and their main purpose is to keep us standing up balanced. Frogs use their back legs a lot, but most of the pressure isn't put on them at all times. Frogs main purpose for their hind legs is to jump. When humans jump, they use a lot of momentum from their arms and upper body. Frogs use just their legs, winding them up just slightly under their body and shooting out like a spring. Because of the different uses of the legs, frogs and humans have different bones in their legs. Humans have three bones in our legs, the femur, the fibula and the tibia. Frogs have a femur, but the fibula and tibia combine into the tibio-fibula. Frogs also don't have patellas, or knee caps, like humans do.

Frogs vs Humans: Reproductive System

The reproductive system was very interesting to learn about. In both frogs and humans, the males produce the sperm and the female produces the eggs. But when it comes to the fertilization, humans reproduction is internal and frogs reproduction is external. The male clings on the females back, squeezes out the egg, and simultaneously, the male fertilizes the egg with sperm. This is very different from human internal reproduction, and both come with their advantages and disadvantages.

Frogs vs Humans: Circulatory System

Human hearts have four chambers, while frog hearts only have three. Frogs do not have an aorta, but humans do. Frogs have a left atrium, a right atrium and a ventricle. Humans' ventricle is split in two, so we have a left atrium, a right atrium, a left ventricle and a right ventricle. The human a heart has a vena cave, but the frog heart does not. They are similar in shape, though. They are both a triangular, oval shape.

Favorites

My favorite part of the lab was learning and see how similar the human body and the frog body actually are. Although my from didn't have anything inside, it was fun to see what other groups found inside their frog's stomach. My least favorite part was taking out certain parts of the body, especially seeing other groups taking out the eggs in their female frogs.

Still Want To Know

I'm still really curious on how frogs breathe through their skin. It is a weird concept to think about, especially because humans can't breathe through their skin, so we don't know exactly what it feels like.

Reflection

My partner and I did a really good job collaborating. We knew what we wanted and needed to get done, split up the workload and got it done in a reasonable amount of time. One thing we could have worked on is critical thinking. When we got, sometimes we asked how the other groups had gotten there, rather than working harder and persevering.