Form6 Biology

Leong13

我不会Hormane 请问雨天之魂如果有空你能不能把你的this topic post上这里.Auxin?

bluedog

Leong13 于 20-3-2005 12:28 PM  说 :
请问what is synapse?我有问题问who can explaine the process of neuronmuscular junction ?

synapes is  link or junction between one neurone and another neurone.responsible for transmiting nerve impulses from neurone to neurone

the process of neuromuscular junction?
是sliding filament theory吗？

1)impulse arrive at neuromuscular junction.
2)vesikel fuse presynaptic membrane.
3)acethycholine realeased.一定是acythycholine
4)depolarization of sarcolemma.
5)action potential is formed in muscle fibre then transmited to t-tubule and vesicles.
6)vesicels release Ca2+
7)ca2+bind to troponin
8)troponin activated
9)tropomyosin displaced
10)ATP binds to myosin head and hydrolysed,releasing energy
11)myosin head then bind to binding site on actin.
cross bridge formed between actin filament and myosin filament
12)power stroke-the myosin head bends as it pulls the actin filament
13)cross bridge detachment occurs as new ATP attaches to the myosin head
14)cocking of the myosin head occurs as ATP in split into ADP and inorganic phosphate
15)cycle of cross bridge formation and derachment repeat until muscle contract fully.
16)I band shortens
H zone shortens
A band unchanged
sacromeres shorten
muscle fibres contracts
注意，只有A band unchanged
17)Ca2+ being collected back by vesicels

bluedog

BluStAr 于 20-3-2005 01:21 AM  说 :
可以大概酱解释 electron transport system mah??
这个最难背了！

我也是这个最不会的了！
很乱！

谢谢坛主

BluStAr

雨天之魂 于 20-3-2005 02:45 PM  说 :




今晚上来收货. 现在要出去一下. 慢点回来再解释.

现在都几点了？
还说晚上？？
骗人！
等到现在都没有！
快点啦，星期三就考试了！

[size=-2]没时间了~

雨天之魂

bluedog 于 20-3-2005 23:16  说 :

the process of neuromuscular junction?
是sliding filament theory吗？

不, If I were you, I'd explain synapse 的 mechanism 先.
然后 neuromuscular junction 的 process 就和一般 synapse 的一样,
只不过对面不是另外一个 synaptic membrane, 而是肌肉.

楼上的再等等, 昨晚线路忙, 上不了啦.
显死, 打了一大堆的东西全部不见, 懒惰马上再来.
等等等, 明天再来收货呗.

BluStAr

雨天之魂 于 21-3-2005 06:51 PM  说 :


不, If I were you, I'd explain synapse 的 mechanism 先.
然后 neuromuscular junction 的 process 就和一般 synapse 的一样,
只不过对面不是另外一个 synaptic membrane, 而是肌肉.

楼上的再等等, 昨 ...

明天？
没信用！

坛主请解释Transport里的Translocation尤其是electro-osmosis, peristaltic wave,protoplasm flow hypothesis和cytoplasmic streaming。谢谢。

BluStAr

lmenwe 于 22-3-2005 05:40 PM  说 :
坛主请解释Transport里的Translocation尤其是electro-osmosis, peristaltic wave,protoplasm flow hypothesis和cytoplasmic streaming。谢谢。

这个书本有哦，个人觉得解释得蛮仔细的。
而且老师说最重要是 protoplasm flow hypothesis...
其他的很少 point...会画它 diagram 应该就很容易了！

[size=-2]完了，他还没上来贴 note....
要靠自己死背了！
放了几次飞机！人家明天就考！

BluStAr

完了，应该不及格了！
没想到很多都是 aplikasi 的问题。
把全部  cycle 背起来都没用。
还要败在英文方面！
竟然有两题有不会的生字，都不懂他问什么！

bluedog

坛主啊，你怎么那么久都给回复啊？
我明天就要考试了啦！！！

坛主请问是不是把Past YearQuestion 做完就可以拿A了。如果是的话我会天天做。

Leong13

坛主啊 坛主啊 坛主啊 ......等到现在都不回复啊?

雨天之魂

说来话长, 这几天忙得死去活来.
连长话短说都不知道要从何说起.

苦矣!~

笔记还得再等. 物主自己要用, 没办法.

lmenwe 于 27-3-2005 17:51  说 :
坛主请问是不是把Past YearQuestion 做完就可以拿A了。如果是的话我会天天做。

不是. 最好就是理解课程里的每一个部分. 不要有盲点.
我化学马是 Past Year 拼命做, 结果还不是死. 靠...

So 要怎样才能拿到A（Bio,Chem）？

Leong13

坛主啊请问可以解释phloem and translocation---mass flow ,electro-osmosis,cytoplasmic streaming and peristalitic waves?????????谢谢坛主............

秋月春风

lmenwe 于 29-3-2005 06:16 PM  说 :
So 要怎样才能拿到A（Bio,Chem）？

勤

每个人都知道的道理，却不是人人做得到。求知识宜脚踏实地：用心理解，背，练习，做足了就凭运气了。

kevinpss

坛主，我的biology很差，现在才想要努力。坛主，如果你有note的话也给我好吗？我的e猫是[email protected]

kevinpss

mass-flow hypothesis
-the mass flow hypothesis or pressure hypothesis postulates that dissolved sugar moves in phloem by means of pressure gradient which exists between the source and the sink.
-the photosynthetic cells in leaves are common source of sugars and the roots are the sink.
-sucrose is actively transport from the mesophyll cells to the companion cell and into the sieve tube against its conc. gradient.this process is called phloem loading.
high conc. of sucrose in the sieve tube lowers the cell water potential.
-water is drawn into the sieve tube from nearby xylem vessel creating a high hydrolystatic pressure which forces the bulk or the mass flow of the phloem sap towards the sink.
-at the root, sucrose is actively transported fromthe sieve tube into the companion cell and into a root cell. this process is called phleom unloading.
-the actual translocation of dissolved sugar in phloem does not require metabolic energy.however,the loading of sugar at the source and the unloading of sugar at the sink require energy derived from ATP.

kevinpss

Electro-osmosis hypothesis
-in electro-osmosis,a potential difference develops across the sieve plate by the companion cell which actively transport potassium ions(k+)into the sieve cell.
-as k+ accumulates at one end of the sieve plate,the magnitude of positive charge creates a potential difference between the sieve plate.
-the potential difference causes the positively charge k+ to move at a fast speed across the sieve plate.as the ions move so do the water and dissolved sucrose which are attrached by the positive charge.
-however,water in the phloem move by osmosis since the accumulation of k+ lower the water potential in the sieve tube compared to the next cell.

creme

biology soil analysis project 里的 texture triangle 要怎么画?
有谁能教教我?