生物同化學問題一問

路的盡頭

第1個關於bio既post ? =]
BIOLOGY
問題如下:

Which of the following blood vessels can regulate the amount of blood flow to a certain organ?
A. aorta
B. arterioles
C. veins
D. capillaries


拜託加埋explain >_< ( 可以用中文 但係 科學名詞用返 英文)


CHEMISTRY
1) atom , molecule , element, ion ,compound 有咩分別?
2) covalent bond , metallic bond , ionic bond , dative covalent bond 可以點分?
3) 點樣先知道D ion既 charged去令到個 element/compound變 stable??
4) 點樣balance 1條式??
5) anion 同 cation 係形容咩野?

-終場ソ使者-

1)
Atom is a particle who contains protons,neutrons and electrons.
An ion forms when an atom loses or gains one or more electrons.It contains positively or negatively charged.
Elements are substances which cannot be broken down into simpler by chemical means.
Compound are substances composed of two or more elements.
Molecule is a particle who made up of non-metals and non-metals.
2)
Covalent bond---Is a bond between non-metals and non-metals.
Metallic bond---Is a bond between metals and metals by a "sea" of mobile electrons.
Ionic bond---Is a bond between metals and non-metals
Dative covalent bond---Is a bond in which the bond pair electrons are provided by anyother atom.
3)
???
4)
Brain used.
e.g. C₃H₈+O₂-->H₂O+CO₂
5)
Anion---An ion who is positive.
Cation---An ion who is negative.

[S]【YU】

印象中...

aorta, arterioles, capillaries 都係送血
其實Bio呢課只要check書就有答案
vein 靜脈 就一定唔係送血ga la.

○笨東東○

第3條 : 應該系over 既 charge 去到 一個 inerts gas / octet / duplet 既electronic configuration 既 = stable

天使ｂ‥◆

回復 2# -終場ソ使者-


    5.cation is positive and anion is negative

tony2006uuu

arterioles
因為做過....

Hinton

1)
Atom is a particle who contains protons,neutrons and electrons.
An ion forms when an atom loses o ...
-終場ソ使者- 發表於 26-1-2010 23:24

covalent bond 同 atom 既definitions 要modify下

atom可以只有一粒proton ->proton(s) 加返括號係s度會好d 因為唔一定係plural
其次 有d atom係冇neutron eg.hydrogen (with the reference of its relative atomic mass:1)

covalent 事實上係可以由metal同non-metal form
只係你地syllabus冇咩強調...

eg.AlCl3
Al係類金屬 Cl係halogen
但兩者form出黎既 係covalent bond
(supplementary inf.
Al 要扔哂果3粒electrons 要用既energy好高 about +10000kjmol^-1)

不過呢d野係al野 但你地334應該會教中六野(見到你地有講dative)
所以d definitions 最好執好少少
到時畀markers捉字蝨就無謂~"~

-終場ソ使者-

其實呢d野係呢到唔洗咁執著
你捉埋我d grammar丫嘛(個句錯左who,應該要用which/that-.-)

Hinton

其實我都見到who個度不過考chem除essay之外 唔理grammar
所以我都冇emphasize


我都唔想雞蛋挑骨頭
但對學術態度要認真嫁嘛= =

我唔係有心潑你冷水
你已經做得好好

只係有d definitions 執得靚d 係保障自己既做法我相信你一定理解:]

paladin

arterioles
as they are one of the sole target for vasodilation/vasoconstriction aided by muscle contraction.