【study group】今年中四，欢迎大家一起来讨论功课上的问题，共同进步~

janicetsq

“从来只有奋斗出来的美丽，没有等出来的辉煌” 共勉之...

janicetsq

@冥冥中注定 @Mushishi @ying97

我有个问题搞不懂～biology的第3课(movement of substances across the plasma membrane )...
movement against the concentration gradient 是从low concentration去high concentration 吗？

sam151188

janicetsq 发表于 6-12-2013 12:38 AM
@冥冥中注定 @Mushishi @ying97

我有个问题搞不懂～biology的第3课(movement of substances across the ...

请允许我用英文解释：

Active transport is indeed require the movement of ions or molecules across cell membrane in a region of LOWER CONCENTRATION to a region of HIGHER CONCENTRATION.

For example:

-Plants normally absorb ions such as potassium, phosphate, nitrate as well as other minerals.
- The concentration of the respective ions in the soil is usually MUCH LOWER than inside of root cells.
- As a result, those ions are absorbed by Active transport.

- For animals,The concentration of Potassium (K+) is HIGHER inside the cell then outside the cell (outside LOWER) whereas
- the concentration of Sodium ions is HIGHER outside the cell then INSIDE the cell (INSIDE LOWER).
-Therefore, the presence of Sodium potatssium pump is to pick three INTERACELLULAR Na+ cells OUT OF the cell and to pick TWO EXTRACELLULAR K+ ions INTO the cell.

(Sodium outside more but STILL PUMP OUT) -- Against concentration gradient.
(Potassium inside more but still PUMP IN)-- Against concentration gradient.

- Both Active transport involves expenditure of energy in the form of ATP.

希望您可以明白~

janicetsq

sam151188 发表于 6-12-2013 01:01 AM
请允许我用英文解释：

Active transport is indeed require the movement of ions or molecules acr ...

我明白了...
还有一个问题第4课(chemical composition of the cell )的...
the effects of changes in pH on the activity of enzymes are reversible . 我不明白这一句的意思～

sam151188

janicetsq 发表于 6-12-2013 01:57 PM
我明白了...
还有一个问题第4课(chemical composition of the cell )的...
the effects of changes in  ...

请允许我用英语解释。。。

- The activity of an enzyme highly depend one active site for it to bind and react with the surface of an enzyme.
- A change in pH value can alter the active sites of the enzyme as well as the substrate.
- For example, high H+ ion concentration under low pH would attach to bind to the active site of the enzyme and would alter the active site of the enzyme, altering the ionic changes of the active site.
-Unlike the effects of temperature where high temperature results in denaturation of the enzyme and it is irreversible, pH enviromnent is reversible and the function of the active site can be restored back to its optimal condition.
- This happens where the ionic charges that are changed which restores the active sites and resumres the enzyme function.

谢谢~

sam151188

一句说完，Reversible 是可以“挽回”，可以“回头”。。。若以上的解释太长，请多多包涵~

janicetsq

sam151188 发表于 6-12-2013 08:13 PM
一句说完，Reversible 是可以“挽回”，可以“回头”。。。若以上的解释太长，请多多包涵~

我明白了...谢谢～

janicetsq

明天 发表于 2-12-2013 09:40 PM
就是这样～
PAPER 1要多做练习，这个不用讲也懂
PAPER 2就是看你背多少东西进去，不过我考spm看到很多k ...

请问要怎么样提升英文写作和加些优美句子呢？

seewpeng

hi...明年即将要步入SPM了。我现在好紧张哦！因为今年成绩不是很理想。

ying97

janicetsq 发表于 16-12-2013 01:50 PM
请问要怎么样提升英文写作和加些优美句子呢？

多读英文书，多练习写作文，
我很喜欢读英文小说（因为华文小说的题材都差不多一样的，乏味）
在一些小说内，可以学到很多vocabulary和idiom，有些比较少人用的，
写作文时，在适当的时候丢下去，
只要你写一些形容词比你的朋友特别的，
老师改了也没那么乏味，分数自然会比较高

明天

janicetsq 发表于 16-12-2013 01:50 PM
请问要怎么样提升英文写作和加些优美句子呢？

你还有时间，现在就多写，最好2天写一篇，然后找老师改，订正，再做。速成法还不适合你。

冥冥中注定

seewpeng 发表于 20-12-2013 05:56 PM
hi...明年即将要步入SPM了。我现在好紧张哦！因为今年成绩不是很理想。

一起努力吧～首先要看看你差的科目，再对症下药

seewpeng

我的语文科很差。所以现在就要拼命读啊！！！

janicetsq

seewpeng 发表于 20-12-2013 05:56 PM
hi...明年即将要步入SPM了。我现在好紧张哦！因为今年成绩不是很理想。

我也是，一起努力吧~趁还有几天假期，温习功课吧！尤其是弱的科目！

janicetsq

ying97 发表于 20-12-2013 09:29 PM
多读英文书，多练习写作文，
我很喜欢读英文小说（因为华文小说的题材都差不多一样的，乏味）
在一些小 ...

好~谢谢~我会去试试的~

janicetsq

明天 发表于 20-12-2013 09:50 PM
你还有时间，现在就多写，最好2天写一篇，然后找老师改，订正，再做。速成法还不适合你。

好~谢谢~

janicetsq

有人知道要怎么换佳礼的账号名吗？我想换个名字

seewpeng

好的。加油！

CCHAPPY

janicetsq 发表于 21-12-2013 07:02 PM
有人知道要怎么换佳礼的账号名吗？我想换个名字

没得换用户名，只能注册新的帐号

janicetsq

VirusAttack 发表于 1-12-2013 03:37 PM
历史其实最重要的是 兴趣
没有了兴趣，那当然你连看都不要看
至于试卷一呢，就多做练习，每天做。我每天做 ...

我终于下载到你的note了~哈哈~谢谢啊~很整齐哦~