Form6 Biology

别问

雨天之魂 于 27-1-2005 09:16 AM  说 :


transport of glucose across membrane 的方式是 facilitated diffusion.
而相关的 channel protein 是一个 uniport system.



糖会 diffuse 入细胞里., 可是更大部分的是细胞的水份会涌出来尝试化淡它 ...

谢谢你。。。
不过我老师所给的笔记里
symptoms of diabetes mellitus
# tiredness due to loss of glucose in urine and poor uptake of glucoses by liver and muscle cells

# muscle wasting due to gluconeogenesis caused by increased glucagon.

浮萍

别问 于 28-1-2005 21:04  说 :


谢谢你哦
不过我一直单纯的以为，glucose可以facilitated diffusion 进cell。。。
所以。。。

Form6 的Biology 需要把glucose如何pass across cell membrane了解得那么详细吗???
其实glucose pass across 不同的细胞会有不同的transport system (glucose transport protein 不同),
form6应该不需知道吧??? (你们所读的facililated diffusion的exp是不是small intestine cell???)
glucose moves into eye lens, brain, liver, muscle, small intestine等等不同的细胞 membrane transport system 都不同.....
为什么会发生muscle wasting??? 简单的说,
因为skeletal muscle cells的membrane transpoter protein 需要insulin 的signalling来摄取blood glucose,而糖尿病的人因为缺乏insulin 或是细胞无法确认insulin 的signal,所以就算血糖很高也不能摄取,而细胞在缺少glucose 的情况下就会breakdown stored glycogen,protein 和fat来produced energy,久之就会引起muscle wasting了.....

雨天之魂

bluedog 于 27-1-2005 14:08  说 :
想知道为什么YY的fetuses会死，还有，when哪个fetus 死在妈妈的uterus后，哪个妈妈还能活吗？哪个fetus的尸体有从妈妈的uterus出来吗，还是流在uterus里？

没办法告诉你为什么会死. 只知道这种搭配能制止它的生命继续下去而已.
foetus 死掉的意思其实也没什么大不了, 就是自然流产而已.
妈妈没大碍. 尸体(可能连形状都还没有, 只是一滩血水而已) 会被排出体外的.

别问

浮萍 于 28-1-2005 11:03 PM  说 :


Form6 的Biology 需要把glucose如何pass across cell membrane了解得那么详细吗???
其实glucose pass across 不同的细胞会有不同的transport system (glucose transport protein 不同),
form6应该不需知道 ...

谢谢你！
呵呵，我明白啦！

不过我们只读到那glucose是polar,hydrophilic,所以是through protein channel
而其他small,uncharge的就through phospholipid bilayer 咯

Leong13

the structure of chlorophyll molecule需要背吗？
有甚么好书 introduce 还有如何背biology，帮帮忙，thank you thank you

蝎杰

请问这是甚么意思？？
the absorption sepctrum and action spectrum are not indentical due to the absorption of light by accessory pigments which increase the spectrum of light that can be absorbed for photosynthesis



雨天之魂，请问你甚么时候post form 6 biology notes??

雨天之魂

Leong13 于 30-1-2005 22:22  说 :
the structure of chlorophyll molecule需要背吗？
有甚么好书 introduce 还有如何背biology，帮帮忙，thank you thank you

不用.
要应付STPM, 市场上一般的中六参考书已经足够.

不用苦背. 先是理解, 再做笔记, 多多简化.
就容易记得了.

雨天之魂

蝎杰 于 31-1-2005 16:50  说 :
the absorption sepctrum and action spectrum are not indentical due to the absorption of light by accessory pigments which increase the spectrum of light that can be absorbed for photosynthesis

-_- 我懒惰去翻译这段东西, 不过我可以说的是, 这段话并不是什么重点.
你只需要知道 chlorophyll a, b, carotenoids 这三个 pigments 都有自己特定部分的 absorption length 好了, 并可以从它们的 graph 上分辨得出哪个是哪个.

雨天之魂，请问你甚么时候post form 6 biology notes??  

不好意思, 最近有些私事要忙, 很要命的. 笔记就没有时间处理了.

bluedog

蝎杰 于 31-1-2005 04:50 PM  说 :
请问这是甚么意思？？
the absorption sepctrum and action spectrum are not indentical due to the absorption of light by accessory pigments which increase the spectrum of light that can be absorbed f ...

means that adsorption spectrum 和 action spectrum 不是相等的！

action spectrum is a graphical representation demonstrating the relationship between the rate of photosynthesis and the wavelength of light waves.

adsorption spectrum is a graphical presentation that show that the percentage or degree of light wavelength adsorption by the leaves or pigments.
But the adsorption spectrum is closely follows the action spectrum suggesting pigments absord more light with effective wavelength for pfotosynthesis.
N we know that chlorophyll a and b spectrum follows closely with the respective action spectrum.this suggests that chlorophyll a and b  is responsible for the absorption of most of the effective light wavelengths for photosynthesis.

[ Last edited by bluedog on 1-2-2005 at 07:33 PM ]

蝎杰

不好意思，请问楼住可用话语解释吗？我好象有点开窍了。

bluedog

action spectrum 是rate of photosynthesis 和 wavelength 的关系but
adsorption spectrum 是 percentage 或者relative or degree of light wavelength adsorpt by the leaves or pigments!
就是在哪个wavelength是，哪个pigment或植物的吸收多少哪个light wavelength来进行photosynthesis!
也可以说是pigment 对哪个wavelength的吸收力吧！

[ Last edited by bluedog on 15-2-2005 at 07:01 PM ]

下个星期我的BIO 要教 VOLUME 2了

请问这是甚么意思？？Triglycerides,steroids and fat-soluble vitamins are absorbed into the lacteal. this lymphatic vessel carries its contents to the thoracic duct and thence into the systemic circulation via the left subclavian vein.

不好意思请问这是甚么意思？？
Mucus secretes from the columnar acts as a lubricant , facilitate the movement of food along the alimentary canal.and mucus forms a protective lining,protecting the cell against digestion by protease and acid.

雨天之魂

Hust 于 20-2-2005 17:15  说 :
请问这是甚么意思？？Triglycerides,steroids and fat-soluble vitamins are absorbed into the lacteal. this lymphatic vessel carries its contents to the thoracic duct and thence into the systemic circu ...

Triglycerides,steroids and fat-soluble vitamins 这些都是以 lipid 的形态存在,
在食道里, 或准确点来说, 在肠里会被人体吸收.
肠壁上有很多 villi(sg. villus) 来增加 surface area.
villi 内部的中心有一个叫 lacteal 的部分, 属于淋巴系统的一部分,
会吸收这些 lipid 形态的物质.

这些物质会被传送过 throacic duct, 最后到血管里.

看图:

thank a lot for your help

不好意思，有些问题想请教 gaseouse exchange .The control is involuntary and involve negative feedback mechanisms.The respiratory centre consist of a group of special nerve cells in the medulla oblongata of the brain.The ventral portion of the respiratory centre acts as the inspiratory centre(increase in rate and depth of inspiration).The dorsal and lateral portions act as the expirationcentre(inhibit inspiration and stimulate expiration.) 帮帮忙.谢谢..谢谢.

雨天之魂

Hust 于 20-2-2005 17:20  说 :
不好意思请问这是甚么意思？？
Mucus secretes from the columnar acts as a lubricant , facilitate the movement of food along the alimentary canal.and mucus forms a protective lining,protecting the cell against digestion by protease and acid.  

mucus 就是那种黏黏的液体, 起到保护和润滑的作用.
呼吸系统里的 mucus 会形成鼻涕,
嘴巴里的 mucus 会形成口水. 这是基本概念.

Columnar 是指食道里的 columnar epithelia, 就是一种内部的表皮,
会分泌出 mucus 来帮助食物在食道里的移动.
mucus 也作为一个保护层, 保护表皮的细胞,
不让食道里的 enzyme 和 acid 伤害到自身.

雨天之魂

Hust 于 20-2-2005 22:08  说 :
The control is involuntary and involve negative feedback mechanisms.The respiratory centre consist of a group of special nerve cells in the medulla oblongata of the brain.The ventral portion of the respiratory centre acts as the inspiratory centre(increase in rate and depth of inspiration).The dorsal and lateral portions act as the expirationcentre(inhibit inspiration and stimulate expiration.)

呼吸系统的控制是自动化的, 牵涉到了 negative feedback mechanism,
也就是说当体内 CO2 多的时候, 呼吸就会加快, CO2 少的时候, 呼吸就会慢下来.

控制呼吸的中心是在脑部 medulla oblongata 中的一群神经细胞.
这个中心的 ventral 部分控制吸气行为(inspiratory), 提升吸气的量和速度.
Dorsal 和 lateral 部分则控制呼气行为(expiratory), 终止吸气行为, 促使呼气行为.

Leong13

不好意思...不好意思...有些问题想请教When carbon dioxide diffuse out with 3 method .who can explain more clerly for me very confused ?Thank you.