On Friday, November 30th our bio 11 class did our first dissection! We have been learning about the different types of Annelids (earthworms) there structures, behaviors characteristic and more. We all can learn by reading and taking notes, but the best way to learn is by seeing it our self getting an hand on experience with it. So our teacher brought us earthworms to dissect, we were partnered up with the person we sit with. Our goal for this dissection was to see our self how the worm's structure are, looking at the brain, the heart, the intestines. We had to name the organs that made up the various systems of the earthworm. The purpose of it was to observe the external and the internal structures of the earthworm anatomy. My partner and I used a total of 3 worms. The first worm we used, would not cut propally and when we finally got it to cut, it cut in half and we ripped the intestines and the structures that were holding the worm together. The same thing happened to the second worm we got, we stretched it out to far so when we went to cut it, it just cut in half. Our third worm we got our friend Mathew to cut it and it finally worked out the way it was suppose to. My partner and I are both girls, so we both were the ones to dissect it. We both found it really weird and gross to see. We got over it when we had to look at it under the microscope. This was a fun yet gross dissection. I learned a lot and it helped me understand worms, and there inside structure. It changed my thoughts on hand on experiences for sure.
Discussion Questions
1) What is the name of the pumping organs of an earthworm ?
The earthworm has five aortic arches that are the pumping organs of an earthworm
6) Among the earthworms structural adapations are its setae? How do you think the earthworm's setae make it well adapted to its habitat ?
I could not find the setae on the worm
7) How is the earthworm's digestive system adapted for extracting relatively small amounts of food from large amounts of ingested soil?
The gizzard helps in this case, it is a muscular organ. It is used to churn the food and help it when it moves onto the intestine where the food absorption occurs.
8) Your dissection of the earthworm did not go beyond segment 32. What will you observe if you dissect the remainder of the worm to its posterior end?
The digestive and excretory system
9) During mating, two earthworms exchange sperm. Fertilization is external, and cocoons are produced from which the young eventually emerge. Refer again to steps 5 and 11, where you located the earthworm's reproductive organs. Use a reference to identify the role of each organ in the reproductive process of the earthworm. On a separate paper, summarize your findings.
Worm number 1 :
Worm number 2 :
These here are close up pictures from the microscope of the brain, intestines, heart, and more
Discussion Questions
1) What is the name of the pumping organs of an earthworm ?
The earthworm has five aortic arches that are the pumping organs of an earthworm
2) Trace the parts of the digestive tract through which food passes
When the soil enters the worm, the pharynx pulls the food in, it would then travel through the esophagus and then it would be moistened. When it is moistened it then goes to the gizzard
3) Which parts of the earthworm serve as its brain? How are these parts connected to the rest of the body?
3) Which parts of the earthworm serve as its brain? How are these parts connected to the rest of the body?
There are two pairs of Ganglia in a worm. One pair is under the pharynx and the other pair is above the ganglia. This serves as the brain, it has ventral nerve cords which connects to all the organs in a earthworm.
4) Which of the parts of the worms body that you saw are included in the excretory system?
4) Which of the parts of the worms body that you saw are included in the excretory system?
I was able to see the Anus, but could not find any others.
5) How can you find out whether an earthworm eats soil ?
5) How can you find out whether an earthworm eats soil ?
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| this is a picture of worm number 2, you can see the soil in here |
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| In this picture, you can see close up from the microscope the soil |
It was simple to find out, when looking through the microscope my partner and i found soil everywhere. I guess it came out when we were cutting the worm open and we may have distoryed an intestine or a cord which caused it all to come out.
6) Among the earthworms structural adapations are its setae? How do you think the earthworm's setae make it well adapted to its habitat ?
I could not find the setae on the worm
7) How is the earthworm's digestive system adapted for extracting relatively small amounts of food from large amounts of ingested soil?
The gizzard helps in this case, it is a muscular organ. It is used to churn the food and help it when it moves onto the intestine where the food absorption occurs.
8) Your dissection of the earthworm did not go beyond segment 32. What will you observe if you dissect the remainder of the worm to its posterior end?
The digestive and excretory system
9) During mating, two earthworms exchange sperm. Fertilization is external, and cocoons are produced from which the young eventually emerge. Refer again to steps 5 and 11, where you located the earthworm's reproductive organs. Use a reference to identify the role of each organ in the reproductive process of the earthworm. On a separate paper, summarize your findings.
Worm number 1 :
.jpg) |
| We cut the first worm open and found this. It is the brain, and the intensities |
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| ... And then it ripped in half. But in this picture you can see the soil that came out when we cut the intestine open. |
Worm number 2 :
These here are close up pictures from the microscope of the brain, intestines, heart, and more
Yay! Better late than never!
ReplyDeleteGreat photos Kesia, sorry you got the soggy worms, or perhaps the scalpel was dull... either way you got some great practice and wrote an excellent entry.
Purpose-4/4
Connection to class-3/4
Personal Reflection-4/4
Conventions-4/4
Requirements-10/10
late -1
24/26