2017 DSE Bio 討論區

冇錯 你啱
更正：
4. 1N (only one chromosome inherited from either of the parent)

5. 1N (only one chromosome inherited from either of the parent)

唔好各位DSE jj 小弟都錯左

即係duplicate左之後係2N
1st division之後係N
2nd division之後都係N

唔係
DNA content in terms of N
After Duplicate 4N

(during and after) Meiosis 1 :
2N since 2 daughter cells are formed

During meiosis 2: 2N
After Meiosis 2: 1N

咁如果1 set chromosome=N既話呢?

樓上解釋左
DNA content =/= ploidy

Meiosis 可以DNA content double but haploid

詳情可以google

其實問你幾多N，就應該用set of chromosome去諗
所以之前我唔應該將no. of DNA content同N掛鈎，兩樣野嚟，我搞錯左
不過考試都未必咁樣問
我相信佢只要求你知All four daughter cells formed after meiotic cell division is haploid (1N) and each of the four duaghter cells contain one DNA copies.

總而言之，你識做2015 Q2(c)就代表你明

無錯啊
C<> DNA content
N <> ploidy

雖然約定俗成，但你概念其實無錯，係符號上出錯而已

DNA content唔係一個specifying term..
你話係ploidy, number of chromosome, DNA base pairs或DNA concentration都唔可以話你錯
Chromosome number其實係數centromere..

DNA bro
咁其實hkeaa都算搞錯？

因為ploidy 又可以用N ; DNA content like 15 dse佢又用N

兩個概念唔同, 但點解佢唔區分好d

即係duplicate左之後係2N
1st division之後係N
2nd division之後都係N

唔係
DNA content in terms of N
After Duplicate 4N

(during and after) Meiosis 1 :
2N since 2 daughter cells are formed

During meiosis 2: 2N
After Meiosis 2: 1N

咁如果1 set chromosome=N既話呢?

樓上解釋左
DNA content =/= ploidy

Meiosis 可以DNA content double but haploid

詳情可以google

其實問你幾多N，就應該用set of chromosome去諗
所以之前我唔應該將no. of DNA content同N掛鈎，兩樣野嚟，我搞錯左
不過考試都未必咁樣問
我相信佢只要求你知All four daughter cells formed after meiotic cell division is haploid (1N) and each of the four duaghter cells contain one DNA copies.

總而言之，你識做2015 Q2(c)就代表你明

無錯啊
C<> DNA content
N <> ploidy

雖然約定俗成，但你概念其實無錯，係符號上出錯而已

DNA content唔係一個specifying term..
你話係ploidy, number of chromosome, DNA base pairs或DNA concentration都唔可以話你錯
Chromosome number其實係數centromere..

明你數centromere 意見

不過我諗好多人會被一開始duplication of chromosomes(2 sister chromatids connected to the same centromere 搞混左..）

DNA bro
咁其實hkeaa都算搞錯？

因為ploidy 又可以用N ; DNA content like 15 dse佢又用N

兩個概念唔同, 但點解佢唔區分好d

如果上面果題,睇番答案既話,咁佢係咪問緊你set of chromosome

上次學校mock essay出DNA個structure點樣令佢stable,難到仆街

DNA bro
咁其實hkeaa都算搞錯？

因為ploidy 又可以用N ; DNA content like 15 dse佢又用N

兩個概念唔同, 但點解佢唔區分好d

如果上面果題,睇番答案既話,咁佢係咪問緊你set of chromosome

應該咁答你：
1N: 不論你用DNA content or set of chromosomes 也好

Meiosis 結果都係1N, 但中間過程理解唔同

所以你覺得用set of chromosomes 方便理解，其實無問題

上次學校mock essay出DNA個structure點樣令佢stable,難到仆街

Essay interesting lol

DNA bro
咁其實hkeaa都算搞錯？

因為ploidy 又可以用N ; DNA content like 15 dse佢又用N

兩個概念唔同, 但點解佢唔區分好d

如果上面果題,睇番答案既話,咁佢係咪問緊你set of chromosome

應該咁答你：
1N: 不論你用DNA content or set of chromosomes 也好

Meiosis 結果都係1N, 但中間過程理解唔同

所以你覺得用set of chromosomes 方便理解，其實無問題

因為結果上，haploid daughter cells 就係half DNA content as the diploid mother cell

只不過中間過程理解完全唔同

佢今次問outcome(結果），所以無問題。

如果問中間過程，咁就會唔同，但應該唔會咁玩gwa(雖然上年有題DNA mc錯到，可以留意下既）

2013 bio level 5 留明

冇錯 你啱
更正：
4. 1N (only one chromosome inherited from either of the parent)

5. 1N (only one chromosome inherited from either of the parent)

唔好各位DSE jj 小弟都錯左

即係duplicate左之後係2N
1st division之後係N
2nd division之後都係N

唔係
DNA content in terms of N
After Duplicate 4N

(during and after) Meiosis 1 :
2N since 2 daughter cells are formed

During meiosis 2: 2N
After Meiosis 2: 1N

咁如果1 set chromosome=N既話呢?

樓上解釋左
DNA content =/= ploidy

Meiosis 可以DNA content double but haploid

詳情可以google

其實問你幾多N，就應該用set of chromosome去諗
所以之前我唔應該將no. of DNA content同N掛鈎，兩樣野嚟，我搞錯左
不過考試都未必咁樣問
我相信佢只要求你知All four daughter cells formed after meiotic cell division is haploid (1N) and each of the four duaghter cells contain one DNA copies.

總而言之，你識做2015 Q2(c)就代表你明

無錯啊
C<> DNA content
N <> ploidy

雖然約定俗成，但你概念其實無錯，係符號上出錯而已

DNA content唔係一個specifying term..
你話係ploidy, number of chromosome, DNA base pairs或DNA concentration都唔可以話你錯
Chromosome number其實係數centromere..

你啱
學到野
點解以前呀SIR唔教數centromere 依家發覺通咗啲

唔係
DNA content in terms of N
After Duplicate 4N

(during and after) Meiosis 1 :
2N since 2 daughter cells are formed

During meiosis 2: 2N
After Meiosis 2: 1N

咁如果1 set chromosome=N既話呢?

樓上解釋左
DNA content =/= ploidy

Meiosis 可以DNA content double but haploid

詳情可以google

其實問你幾多N，就應該用set of chromosome去諗
所以之前我唔應該將no. of DNA content同N掛鈎，兩樣野嚟，我搞錯左
不過考試都未必咁樣問
我相信佢只要求你知All four daughter cells formed after meiotic cell division is haploid (1N) and each of the four duaghter cells contain one DNA copies.

總而言之，你識做2015 Q2(c)就代表你明

無錯啊
C<> DNA content
N <> ploidy

雖然約定俗成，但你概念其實無錯，係符號上出錯而已

DNA content唔係一個specifying term..
你話係ploidy, number of chromosome, DNA base pairs或DNA concentration都唔可以話你錯
Chromosome number其實係數centromere..

你啱
學到野
點解以前呀SIR唔教數centromere 依家發覺通咗啲

因為out c centromere 呢個字...

Some examples of questions involving data analysis (by no means exhaustive)

2014 DSE Paper 2 Q2(bi)


2009 AL Paper 1B Q10(a)


2012 DSE Paper 2 Q1(ai)

唔係
DNA content in terms of N
After Duplicate 4N

(during and after) Meiosis 1 :
2N since 2 daughter cells are formed

During meiosis 2: 2N
After Meiosis 2: 1N

咁如果1 set chromosome=N既話呢?

樓上解釋左
DNA content =/= ploidy

Meiosis 可以DNA content double but haploid

詳情可以google

其實問你幾多N，就應該用set of chromosome去諗
所以之前我唔應該將no. of DNA content同N掛鈎，兩樣野嚟，我搞錯左
不過考試都未必咁樣問
我相信佢只要求你知All four daughter cells formed after meiotic cell division is haploid (1N) and each of the four duaghter cells contain one DNA copies.

總而言之，你識做2015 Q2(c)就代表你明

無錯啊
C<> DNA content
N <> ploidy

雖然約定俗成，但你概念其實無錯，係符號上出錯而已

DNA content唔係一個specifying term..
你話係ploidy, number of chromosome, DNA base pairs或DNA concentration都唔可以話你錯
Chromosome number其實係數centromere..

明你數centromere 意見

不過我諗好多人會被一開始duplication of chromosomes(2 sister chromatids connected to the same centromere 搞混左..）

唔係我意見嚟
係做research都係約定做咁數chromosome number
例如做fluorescent in situ hybridization都係stain centromere做reference

DNA bro
咁其實hkeaa都算搞錯？

因為ploidy 又可以用N ; DNA content like 15 dse佢又用N

兩個概念唔同, 但點解佢唔區分好d

冇搞錯
DNA content就係講緊入面有乜DNA 相關嘅野
唔係專有名詞嚟

DNA bro
咁其實hkeaa都算搞錯？

因為ploidy 又可以用N ; DNA content like 15 dse佢又用N

兩個概念唔同, 但點解佢唔區分好d

冇搞錯
DNA content就係講緊入面有乜DNA 相關嘅野
唔係專有名詞嚟

咁meiosis 出現DNA double but haploid 情況時（meiosis 1)

呢個時候點用符號區分？

DNA bro
咁其實hkeaa都算搞錯？

因為ploidy 又可以用N ; DNA content like 15 dse佢又用N

兩個概念唔同, 但點解佢唔區分好d

冇搞錯
DNA content就係講緊入面有乜DNA 相關嘅野
唔係專有名詞嚟

咁meiosis 出現DNA double but haploid 情況時（meiosis 1)

呢個時候點用符號區分？

Haploid 係指half of normal somatic ploidy
咩叫haploid出現meiosis?
Only a somatic cell carried out meiotic cell division can form haploid cell

Human somatic cell = 2n, 2x=46

DNA bro
咁其實hkeaa都算搞錯？

因為ploidy 又可以用N ; DNA content like 15 dse佢又用N

兩個概念唔同, 但點解佢唔區分好d

冇搞錯
DNA content就係講緊入面有乜DNA 相關嘅野
唔係專有名詞嚟

咁meiosis 出現DNA double but haploid 情況時（meiosis 1)

呢個時候點用符號區分？

Haploid 係指half of normal somatic ploidy
咩叫haploid出現meiosis?
Only a somatic cell carried out meiotic cell division can form haploid cell

After meiosis 1:
no of chromosomes in each daughter cell = mother cell = 2N
But daughter cell is haploid (1N)

DNA bro
咁其實hkeaa都算搞錯？

因為ploidy 又可以用N ; DNA content like 15 dse佢又用N

兩個概念唔同, 但點解佢唔區分好d

冇搞錯
DNA content就係講緊入面有乜DNA 相關嘅野
唔係專有名詞嚟

咁meiosis 出現DNA double but haploid 情況時（meiosis 1)

呢個時候點用符號區分？

Haploid 係指half of normal somatic ploidy
咩叫haploid出現meiosis?
Only a somatic cell carried out meiotic cell division can form haploid cell

After meiosis 1:
no of chromosomes in each daughter cell = mother cell = 2N
But daughter cell is haploid (1N)

Yes, so anything after meiosis is always n
What is ur question?

DNA bro
咁其實hkeaa都算搞錯？

因為ploidy 又可以用N ; DNA content like 15 dse佢又用N

兩個概念唔同, 但點解佢唔區分好d

冇搞錯
DNA content就係講緊入面有乜DNA 相關嘅野
唔係專有名詞嚟

咁meiosis 出現DNA double but haploid 情況時（meiosis 1)

呢個時候點用符號區分？

Haploid 係指half of normal somatic ploidy
咩叫haploid出現meiosis?
Only a somatic cell carried out meiotic cell division can form haploid cell

After meiosis 1:
no of chromosomes in each daughter cell = mother cell = 2N
But daughter cell is haploid (1N)

After meiosis 1
DNA content in each daughter cell is 2N(since there is a set of duplicated chromosomes)

But the daughter cell itself is a haploid due to separation of homologous chromosomes

DNA bro
咁其實hkeaa都算搞錯？

因為ploidy 又可以用N ; DNA content like 15 dse佢又用N

兩個概念唔同, 但點解佢唔區分好d

冇搞錯
DNA content就係講緊入面有乜DNA 相關嘅野
唔係專有名詞嚟

咁meiosis 出現DNA double but haploid 情況時（meiosis 1)

呢個時候點用符號區分？

Haploid 係指half of normal somatic ploidy
咩叫haploid出現meiosis?
Only a somatic cell carried out meiotic cell division can form haploid cell

After meiosis 1:
no of chromosomes in each daughter cell = mother cell = 2N
But daughter cell is haploid (1N)

Yes, so anything after meiosis is always n
What is ur question?

After meiosis is N

但meiosis has 2 stages
Meiosis 1 and 2

After meiosis 1,
DNA content in each daughter cel is 2N
But daughter cell is haploid 1N

So 1999 lol

DNA bro
咁其實hkeaa都算搞錯？

因為ploidy 又可以用N ; DNA content like 15 dse佢又用N

兩個概念唔同, 但點解佢唔區分好d

冇搞錯
DNA content就係講緊入面有乜DNA 相關嘅野
唔係專有名詞嚟

咁meiosis 出現DNA double but haploid 情況時（meiosis 1)

呢個時候點用符號區分？

Haploid 係指half of normal somatic ploidy
咩叫haploid出現meiosis?
Only a somatic cell carried out meiotic cell division can form haploid cell

After meiosis 1:
no of chromosomes in each daughter cell = mother cell = 2N
But daughter cell is haploid (1N)

After meiosis 1
DNA content in each daughter cell is 2N(since there is a set of duplicated chromosomes)

But the daughter cell itself is a haploid due to separation of homologous chromosomes

就算冇duplication都係2n
2n係指somatic cell ploidy
同duplication冇關係
假如個生物係tetraploid, after meiosis the gamete is still haploid

我意思佢after meiosis 1
又可以2N 又可以1N

好麻煩jeh...

點解唔統一計chromosomes 用C
計ploidy 用 N?

DNA bro
咁其實hkeaa都算搞錯？

因為ploidy 又可以用N ; DNA content like 15 dse佢又用N

兩個概念唔同, 但點解佢唔區分好d

冇搞錯
DNA content就係講緊入面有乜DNA 相關嘅野
唔係專有名詞嚟

咁meiosis 出現DNA double but haploid 情況時（meiosis 1)

呢個時候點用符號區分？

Haploid 係指half of normal somatic ploidy
咩叫haploid出現meiosis?
Only a somatic cell carried out meiotic cell division can form haploid cell

After meiosis 1:
no of chromosomes in each daughter cell = mother cell = 2N
But daughter cell is haploid (1N)

Yes, so anything after meiosis is always n
What is ur question?

After meiosis is N

但meiosis has 2 stages
Meiosis 1 and 2

After meiosis 1,
DNA content in each daughter cel is 2N
But daughter cell is haploid 1N

So 1999 lol

有冇meiosis I都係2n

DNA bro
咁其實hkeaa都算搞錯？

因為ploidy 又可以用N ; DNA content like 15 dse佢又用N

兩個概念唔同, 但點解佢唔區分好d

冇搞錯
DNA content就係講緊入面有乜DNA 相關嘅野
唔係專有名詞嚟

咁meiosis 出現DNA double but haploid 情況時（meiosis 1)

呢個時候點用符號區分？

Haploid 係指half of normal somatic ploidy
咩叫haploid出現meiosis?
Only a somatic cell carried out meiotic cell division can form haploid cell

After meiosis 1:
no of chromosomes in each daughter cell = mother cell = 2N
But daughter cell is haploid (1N)

After meiosis 1
DNA content in each daughter cell is 2N(since there is a set of duplicated chromosomes)

But the daughter cell itself is a haploid due to separation of homologous chromosomes

就算冇duplication都係2n
2n係指somatic cell ploidy
同duplication冇關係
假如個生物係tetraploid, after meiosis the gamete is still haploid

Ok!
咁我明你意思
總之用N就計ploidy ; C就計no of chromosomes

兩者都可以以DNA content 表達