Comments on: Dissection: The Dogfish Shark Uncovered

by: michael

Sat, 17 May 2008 18:58:36 +0000

I really enjoyed this lab. It is one thing to learn about organ systems and anatomy in the classroom but when you actually get to see it, it brings a much greater understanding. Before I disected the shark, I never realized how large a shark’s liver was. This is clearly an adaption that helps the shark remain more bouyant. I was also amazed at getting to see the cartilage first hand. Even the skull was made of the light weight cartilage which would help it to swim faster and also aid in bouyancy. Seeing a sharks anatomy first hand really helped aid my learning.

by: Danny

Sat, 17 May 2008 15:55:11 +0000

For the day that I got to do it, the shark dissection lab was awesome! I thought it was really cool to scrape off the sharks upper head to find its brain. I was really shocked though at how rough the sharks skin was. Of course, i have never been upclose to an alive shark and this was my first time seeing one in person. I would have guessed that the shark’s skin would have been smoother. Great post Ali!

by: Taylor

Sat, 17 May 2008 14:46:16 +0000

One of the biggest things I learned was how large their liver was and this may sound stupid, but how similar their insides are to ours. I guess I just figured aquatic would have TONS of different adaptations we don’t have, but that wasn’t what I found.
But, to answer your question, another adaptation they have is their gills being so close to their heart and major arteries which makes the diffusing of oxygen into the blood stream quicker. Also, the folds, I think they were called rugae, in the stomach and intestines helped nutrients transfer and such.
It was a really interesting lab but, I’m pretty squeamish so I keep my distance! But it was still a lot of fun!
I like the pictures Ali, good post!

by: Alex

Sat, 17 May 2008 13:30:46 +0000

I learned that the organs are highly folded to maximize surface area in the shark. The adaption of fins allows the sharks to balance and navigate through the water. Also there great sense of sense of smell is their main way of locating prey, because their vision is not so great. I discovered that the gills are also highly folded, and they make the shark able to breath in the water.

by: maryclaire

Sat, 17 May 2008 13:04:24 +0000

This lab was different than any other dissection i’ve ever been a part of. For one, like Ali said, we had our own shark to dissect in small groups. I thought that was pretty cool. Also i found how to tell if the shark is female or male. Being able to see the brain also was facinating. This website shows the external anatomy of a dogfish shark with some differen tscientific terms than we had learned in class. It’s a great visual: http://www.pc.maricopa.edu/Biology/ppepe/BIO145/lab04_1.html Here is a website with some more basic facts about the dogfish shark like where it lives, its habits, general range of where it lives, etc. check it out:http://www.gma.org/fogm/mustelus_canis.htm
This dissection was very interesting and a perfect one to end the year with. I know I learned alot.. anyone else? : ) & good post ali! I liked the pictures of your class!

by: steven t

Sat, 17 May 2008 04:05:08 +0000

i dont know why but when i think about animals like the shark i imagine them having very different bodies entirely. not that sharks are alike humans in appearance but they have all the same internal body parts for the most part. the lab helped me to put it in perspective. it was also interesting to learn about the sharks adaptations to living in aquatic environments like the enlarged liver for buoyancy. also it gave me a chance to see what some of the human organs look like, such as the stomach and intestines. it was a very interesting lab and was pretty fascinating.

by: Roger

Sat, 17 May 2008 03:59:55 +0000

I for one learned a lot from this dissection. It was a lot a fun and taught me a lot about sharks, especially the Dogfish. I learned that the liver in a Dogfish is huge! If it was put to scale for a human, it would take up our entire abdomen. The reason was for extra buoyancy, the liver had oilsi in it that caused this buoyancy. It was very interesting and very fun! Here is a website that has a bit about the Dogfish, Enjoy!
http://www.nefsc.noaa.gov/sos/spsyn/op/dogfish/

by: jake

Sat, 17 May 2008 03:40:24 +0000

Wow ali, great post! This was by far the most interesting lab we have done all year! It really helped to be able to see the things, up close, that we had been learning about. Our group’s shark was a bit different than the others. Surprisingly it didn’t have a liver. Our group had to go over to a different shark in order to lean about the properties of the shark’s liver. The liver was coated in an oily substance which repelled water therefore allowing it to float and help the shark control its levels of depth. One interesting thing that our group discovered about our shark was, well..that it had three ovaries. I didn’t even think that this was possible, but i guess it was. This was a very interesting and insightful lab, good post!

by: Brantley

Sat, 17 May 2008 02:49:44 +0000

This lab was so much fun! I learned so much. It was incredible to see how much space the liver took up! My favorite part of the lab was seeing the inside of the intestine. We got to see how the structure of the intestine helps with the absorbtion of water.

by: morgan

Sat, 17 May 2008 02:28:05 +0000

That lab was interesting Ali and also really fun! I can’t believe that liver is sooo big!! The coolest thing about the liver was when Miss Baker but it in water and it floated because the shark wanted to stay bouyant and not sink to the bottom of the ocean. Another interesting fact I learned was that, especially in the digestive tract, the body naturally coils to make more room and surface area, which I was unaware of until Evelyn had to point it out. While researching I found pretty cool things about the dogfish sharks teeth. Onee website said “The smooth teeth are located in rows which rotate into use as needed. The first two rows are used in obtaining prey, the other rows rotate into place as they are needed. As teeth are lost, broken, or worn down, they are replaced by new teeth that rotate into place. ” http://www.enchantedlearning.com/subjects/sharks/species/Dogfish.shtml
On another website I found the actual dissection we did but in more detail. Check it out at http://www.amnh.org/learn/pd/sharks_rays/rfl_dissection/

by: Rachel P

Sat, 17 May 2008 02:06:41 +0000

Great post Ali! I thought the disection was actually really cool and I learned alot about sharks too.One thing I thought was really interesting was the fact that the shark’s heart was so much smaller than it’s other organs. I actually found this website http://www.sharkinformation.org/all-facts/ when i was looking for facts about sharks. It has a ton a of shark facts that were actually pretty interesting. Some of the facts are: sharks use over 20,000 teeth in its lifetime, two thirds of a shark’s brain is dedicated to sense of smell, and the most harmless sharks tend to be the largest ones, such as the Megamouth shark and the Whale shark.

by: Blake

Sat, 17 May 2008 02:01:57 +0000

First off, i really liked dissecting the sharks, this was definantly the most fun lab of the year. I also learned a lot that i didnt know about sharks in the process. During this dissection i learned a lot about sharks. I really liked seeing how the parts of the body in the shark were similar and different than in humans. I thought it was interesting how the sharks brain was very separated and not as centralized as it is in humans. Also i would have never guessed that the liver of it was that big. One adaptation i saw the shark had was its skin, if you rub the shark from posterior to anterior then it is very rough but if you rub it the other way it is quite smooth. This is due to things called denticles on the sharks skin. They grow toward the back of the shark to make it more streamlined in the water so it can swim faster. I found a website that has information on the dogfish shark as well as many other sharks. http://www.new-brunswick.net/new-brunswick/sharks/species/spinydogfish.html . Good post and thank you Miss Baker for letting us do this lab, it was alot of fun and i learned a lot.