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2017 DSE Biology suggested answer 生物科答案 + 感想



感謝同學提供試卷

Paper 1A    ( 內裡答案不代表 DSE00 答案 )
Whole set official marking

1      CBAAA   6      CCBAD
11    DBABA   16    DCDBB
21    BCDCA   26    DCACD
31    DDCBA   36    A

       Explaination

2.        There are intestinal amylase.
3.         At the "beginning", maltose is absent 
           Enzyme is protein and give positive result in protein test.
4.         Tube P is a control set-up    (not sure)
14.       The measurement is cutting the shoot until color appear. So the water level is not  a concern.
17.       Support of a 'leaf’
21.       Embryo cell not likely enlarge in a such small space.
31.       P is region of differentiation but not elongation.

       感想

做左 MC,感覺上唔難,係頭幾條有 D tricky 之外,其他個D都好直路,如果 LQ 程度同 MC 一樣,Cufoff 應該會上升 1~2 分。


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18 Comments

  1. 10) 點解會有mutation? genetic variation 唔係已經足夠令speciation發生? 題目亦都冇講有mutagen出現, 答案會唔會應該係C?
    21) 點解冇cell enlargement? cell divide 之前全部都要經過interphase, 當中唔係已經包括咗cell enlargement咩? 同埋點解又會有cell differentiation? 就例如點解我哋可以用embryo blastocyst嘅cell 做stem cell, 乜唔係正正因為cell of embryo are not differentiated? 所以答案會唔會係A?
    18) C 呢一個選擇會唔會調轉咗因果關係呢 正正因為aorta係將血傳輸到身體唔同部分 所以就要bumping action of heart幫手 高嘅血壓指係佢嘅結果 唔係佢嘅原因。 所以答案會唔會係D? (for a shorter diffusion distance)

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    1. 18 認同
      10 not sure because of the word "likely"
      21 cell enlargement 唔似有,因為佢地個size 唔似有enlarge到

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    2. 21 same magnification, so how come they show cell enlargement...

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    3. 21 佢放左係個Dish入面,個cell點樣大過本來佔哂個Dish嘅cell?自己諗下
      10 冇mutation嘅話何來genetic variation?唔係隻隻species原來都有adapt到其他環境嘅recessive gene.
      再加上Spontaneous mutation根本唔需要mutagens出現.

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    4. gamete production 已經有genetic variation, 自身mutation 產生的genetic variation相比crossing-over/inde. assortment 製造的variation 微不足道吧?特別係自身body 會修復部分mutation 的

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    5. Crossing over independent assortment都只係隨機分配parents本身有嘅allele喎師兄 如果本來唔存在adapt環境嘅allele又點分到出黎?

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    6. 再加上佢問你likely to occur 微不足道唔算有? 又或者修補咗都係發生咗mutation啦 Goodest logic

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    7. 隨機分配parents本身有嘅allele都會製造到new genetic combination which may favour the environment,仲有likely to occur 就不了:( 我都get唔到佢意思係necessary定點樣,mutation happens all the time 佢玩曬,thanks for ching's goodest logic<3

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    8. 如果冇mutation,咁你覺得白色既樹係點黎?

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  2. Early development of embryo 好似唔係syllabus

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  3. 第4題應該係C 四個選項都係正確嘅描述 但題目問嘅係哪項不是實驗設立的目的 而實驗其實是為咗觀察enzymatic reaction of enzyme X. Setting up starch solution and boiled enzyme X其實係證明starch and denatured enzyme X撈埋嘅時候唔會有反應;而唔係證明enzyme X煲完之後會denatured.(呢個並唔係實驗嘅重點)

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    1. But I contend that A is still the correct ans, as the purpose of control set-up with starch in it is to observe if starch will decompose on its own under heat.

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  4. Furthermore, without experiment we cannot eliminate the possibility that enzyme X has no effect while denatured enzyme X is an inhibitor on the reaction of starch decomposition.

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  5. Actually if u look carefully for q21, u will find that a cell is dividing so smaller cells will form but later photo will show larger cell so we can conclude cell enlargement

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  6. Moreover, cell differentiation must be wrong since at the moment no cells are induced to perform different function, indicating cell differentiation don't occur yet especially they have not yet implant to uterus

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  7. 點解29系c。。。。唔系只會系axon有synapse咩?

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    Replies
    1. Neurone之間都有synapse 應該係

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  8. 17題 guard cell好似都係thin wall cell?如果係嘅話唔係都可以support by tugidity of thin wall cell咩?

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