help with school project: giant squids

[bmin]

Hi

I'm a highschool student and as my AP biology final project, I have chosen to research the giant squid.

I was wondering if anyone can tell me anything about the giant squid's nervous system. I read somewhere that it's about 5 times more sensative than the nervous system of a human. I can't seem to find a reliable source.
And can someone explain about the ammonium in the squid's body?(i.e. where is it produced, any other purpose other than staying afloat)

What data (that have been collected) do the scientists draw their conclusions about the giant squids from?

If you have time, I would really appreciate it if you could give me helpful links for my project.


Thank you so much!

 

[WhiteKiboko]

Try hitting the blue science tab at the top of the page.... steve and kat have some articles you may find helpful... among them i would suggest the giant squid factsheet....

hope this helps

 

[monty]

I was wondering if anyone can tell me anything about the giant squid's nervous system. I read somewhere that it's about 5 times more sensative than the nervous system of a human. I can't seem to find a reliable source.

And can someone explain about the ammonium in the squid's body?(i.e. where is it produced, any other purpose other than staying afloat)

We had a discussion about the ammonia a month or 2 back, but didn't really figure out optimal references-- I think it came up when I was grumbling about how there is some bogosity in the wikipedia giant squid page (some of which I corrected, some of which I corrected and others uncorrected, and some of which I'm still looking for the right answer on....) Anyway, searching for ammonium should bring that up.

I'm not sure what "5x as sensitive" means in the context of nerves-- sensitivity usually refers more to sense organs than the nerves themselves. There is a survey about giant squid nervous systems by JZ Young-- I think it's in the "Proceedings of the Royal Society" journal, which you can probably find in a university library. Common small squids have a "squid giant axon" which occasionally gets called a "giant squid axon" causing people to think it's from a giant squid; it's possible that this is what you've heard about. Studying the small squid giant axon is actually how neurobiologists learned how nerves work in all critters, including humans, because it was so thick scientists could stick electrodes in it before they had developed microelectrodes and really good amplifiers. The reason it's so big is that one way of making nerves transmit signals fast is to make the nerve thicker-- the giant axon is part of the squid's escape reflex, so it allows the squid to contract its mantle and jet away very rapidly when it senses a threat. In humans (and other vertebrates) nerve signals are sped up using a different method, by coating the nerve with a sheath of myelin, in an arrangement that allows the nerves to be just as fast but not thick like the squid's. Anyway, the basic signal propogation mechanism is the same in the squid, including its giant axon, so two scientists named Hodgkin and Huxley studied the squid axon as the key to understanding the fundamentals of neurophysiology, and that turned out to be representative of how all nerves work.

Hope this helps, good luck on your project!

- M

 

[chrono_war01]

We had a discussion about the ammonia a month or 2 back, but didn't really figure out optimal references-- I think it came up when I was grumbling about how there is some bogosity in the wikipedia giant squid page (some of which I corrected, some of which I corrected and others uncorrected, and some of which I'm still looking for the right answer on....) Anyway, searching for ammonium should bring that up.

I'm not sure what "5x as sensitive" means in the context of nerves-- sensitivity usually refers more to sense organs than the nerves themselves. There is a survey about giant squid nervous systems by JZ Young-- I think it's in the "Proceedings of the Royal Society" journal, which you can probably find in a university library. Common small squids have a "squid giant axon" which occasionally gets called a "giant squid axon" causing people to think it's from a giant squid; it's possible that this is what you've heard about. Studying the small squid giant axon is actually how neurobiologists learned how nerves work in all critters, including humans, because it was so thick scientists could stick electrodes in it before they had developed microelectrodes and really good amplifiers. The reason it's so big is that one way of making nerves transmit signals fast is to make the nerve thicker-- the giant axon is part of the squid's escape reflex, so it allows the squid to contract its mantle and jet away very rapidly when it senses a threat. In humans (and other vertebrates) nerve signals are sped up using a different method, by coating the nerve with a sheath of myelin, in an arrangement that allows the nerves to be just as fast but not thick like the squid's. Anyway, the basic signal propogation mechanism is the same in the squid, including its giant axon, so two scientists named Hodgkin and Huxley studied the squid axon as the key to understanding the fundamentals of neurophysiology, and that turned out to be representative of how all nerves work.

Hope this helps, good luck on your project!

- M

I never knew that before, thanks for educating the uneducated!

 

[Squidman]

I had to read that several times to get that information stuck in my head.