this week in science #9

This week in science I dissected a skate. Which is closely related to a shark but looks like a ray fish. I also learned the anatomy of the skate before we actually dissected the skate. At first it was difficult to cut the skate because of its cartilage instead of bone. So we took a scissor to cut an incision down the middle of the ventral side. When we finished that we saw the liver, intestine, and stomach.

What I learned is that a skate doesn't have bones it has cartilage. Cartilage is firm, flexible tissue found in the internal ear, nose, elbow, knee etc. But it is still very difficult to cut because of this. I learned that the hard way hen trying to make an incision in the skate's chest. What I also learned was that the skate's brain is at the side of the skate's head.

The two organisms that were dissected were the frog and skate. The brain, eyes and skin were a few examples of functions that work the same but appear different. One similarity for the brain, eyes, and skin of the frog and skate is that each allow its host to adapt to its environment effortlessly. Allowing them to think quickly, see predators, and evade predators using camouflage. A difference for the brain, eyes, and skin are that the skate is able to make quick last minute decisions, its eyes are able to adapt to the dark parts of the ocean. While its skin allows it swim with little effort. The frog's brain although small comes in use. While the eyes allow the frog to see thing behind it. Also its skin in covered in mucus to that it appears slippery to predators.

This Week In Science #8

This week in science we were able to dissect animals. Our choices were a grasshopper or crayfish. My partner and I chose to dissect a crayfish. What I did was first learn the anatomy of the crayfish. Then after learning the anatomy we took a whole crayfish an we were able to see the anatomy in person. Afterwards we began the dissetion. We were able to see and indentify the parts of an crayfish. We could see the dorsal view when we put it on its stomach, the ventral view when it was on its back. The posterior part of the crayfish is the tail and the anterior is the head. The crayfish are able to adapt to many environments except very cold ones. They live in environments such as marshes, rivers, lakes etc. They are not able to survive long in salt water, due to their genetic make up features of not being able to sustain in that type of environment.

I learned that there are more body parts to a crayfish then meets the eye. They are invertebates meaning they don't have bones. It also has 5 legs on each side of its body. They also have an exoskeleton that protects their inner body parts from harm against predators. Some can grow to the size of a cat, while others are as tiny as a thumbnail. They also have pinchers to ward off predators. They have antennas to feel, see, and taste things.