蜗牛到底有没有眼睛？

KyleMichelleGo

快要发疯了，蜗牛到底有没有眼睛？

给你一题：蜗牛和蚂蚁，试说出不同点

蚂蚁有眼睛，蜗牛没有

可以吗？

雨天之魂

不行不行~~
蜗牛有眼睛..看我转载来的这段东西.

" Most gastropods have a small eye at the base of each tentacle, but in some the eyes are enlarged and on stalks. Primitve snails have eyes consisting of a hollow lined with cells that are sensitive to light, this woudl not allow them to see very well but woudl allow them to detect large objects and light sources. More advanced snails have a cornea and lens, which would allow image formation, but can't focus in the same way as vertebrate eyes, becuase the shape and position of the lens cannot be changed, and there is no iris (the part of the eye that narrows and widens when its dark or light). "




[ Last edited by 雨天之魂 on 27-9-2004 at 01:39 PM ]

雨天之魂

蚂蚁跟蜗牛的不同点?

蚂蚁有脚, 蜗牛没有丫~~~~
蚂蚁有 segmented body, 蜗牛没有丫..

干嘛说眼睛~~~~~~~~~~~~~

KyleMichelleGo

谢谢你的指教。
眼睛因为我要写5种不同点，SEGMENTED BODY和脚都已经提出来了！
呵呵，这令我班发生了一些趣事！我都说卡通不骗小孩的。。

雨天之魂

一点也没有错...
呵呵呵呵...





可是要注意噢...
卡通有时候会骗人的噢..
不管有没有披上那个红红色的披风, 人是飞不上天的..别学超人

wanmeijuxie

那麽還有其他三個不同點呢？是什麽？
蝸牛有shell算是嗎？
不好意思。。。

雨天之魂

蚂蚁 (arthropod)                 蜗牛 (gastropod)

-segmented body                  -non-segmented body
-with joint legs                 -without joint legs
-chitinous exoskeleton           -shell
-分得出 head, thorax, abdomen    -分不出.
-compound eye                    -non-compound eye <-- 这个就对了.
-蚂蚁走得快                      -蜗牛爬得慢..

实在是不容易啦..最后一个完全是乱掰了..
等别人来说吧.

关于眼睛的, 有些东西要补充.

Most ants have two compound eyes, which are made up of light-sensitive compartments called ommatidia. These compartments work together to generate an image in the ant’s brain. Some types of ants have three simple eyes, called ocelli, at the top of their heads. Ocelli can detect light, but they do not form images. Different species of ants vary in their ability to see: Some have well-developed sight, but others are entirely blind. Sight is of little importance to those ants that spend all or much of their lives underground.

雨天之魂

绮丽米雪兄, 我反复思考后,
实在是有些好奇你到底考试的时候写了什么,
可以分享一下吗?

wanmeijuxie

雨天之魂 于 27-9-2004 02:17 PM  说 :
蚂蚁 (arthropod)                 蜗牛 (gastropod)

-segmented body                  -non-segmented body
-with joint legs                 -without joint legs
-chitinous exoskeleton           -sh ...

先謝啦，還肯搭理我。。。
不好意思，
我有個疑問，
segmented body 及 分得出head thorax,abdomen 有什麽分別？

雨天之魂

什么嘛..我天天都在这里, 你们自己说说下忽然没有话罢了..

segmented body, 给个例子, 你想象一下马陆, 蜈蚣.. 它们都是 segmented 的, 可是你分得出吗?
还有, 虾, 虽然它也是 segmented body ,可是它的 head 跟 thorax 合并在一起, 很难分出来, 所以它身体的部分只分为 cephalothorax( head + thorax 的意思) 和 abdomen.

蚂蚁的身体就很明显有头, 喉部, 肚子.

所以, segmented body 跟 分得出 head, thorax, abdomen 是不一样的.

wanmeijuxie

收到了！
謝謝！

雨天之魂

在做总复习的时候念到一些东西关于比较的...
上来做少少补充.

gastropods 有一个叫 muscular foot 的构造, 是其他 phyla 没有的.
可以算是一个 unique 的 characteristic.

还有, snail 不会 bilateral symetrical.

铁蛋

稍微补充：

1. Snails are hermaphrodites (having both male and female sexual reproduction organs); Ants are clearly separated into male and female ants.

2. Snails are diploid; Male ants are haploid (parthenogenesis - development from unfertilized egg) while female ants are diploid.

3. Snails are solitary organisms; Ants are social animals that form colonies.

希望有帮助！