biology syllabus stpm

(b) Struktur yang ditunjukkan dalam gambar rajah di bawah berkaitan dengan organ pada (a).

KL

(i) Namakan struktur K dan L. [2 markah]

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(ii) Berikan dua ciri bagi setiap struktur itu. [2 markah]

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(iii) Mengapakah struktur dinding bagi K dan L berbeza? [1 markah]

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3 A researcher carried out a cross on pea plants to determine the inheritance of seed forms. He
crossed pure line wrinkled seed with pure line smooth seed to produce F1 generation and subsequently
F2 generation. A total of 250 plants were produced in F2 generation, 59 with wrinkled seeds and 191
with smooth seeds. The diagram below illustrates the crosses.

X
Progeny Q

(a) What is the phenotype of progeny Q? [1 mark]

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(b) What is the expected ratio of wrinkled-seed plants to smooth-seed plants of F2 generation?
[1 mark]

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(c) Using the expected ratio in (b), determine the expected number of phenotypes of F2
generation.

Phenotype Observed number Expected number

Wrinkled 59

Smooth 191

[2 marks]

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3 Seorang penyelidik telah membuat kacukan terhadap pokok kacang pea untuk menentukan
perwarisan bentuk biji. Beliau mengkacukkan baka tulen biji yang berkedut dengan baka tulen biji
licin untuk menghasilkan generasi F1 dan seterusnya generasi F2. Sebanyak 250 tumbuhan telah
dihasilkan dalam generasi F2, 59 dengan biji berkedut, dan 191 dengan biji licin. Gambar rajah
di bawah menunjukkan kacukan tersebut.

Biji berkedut

Biji licin

Induk betina Induk jantan
X

Progeni Q

(a) Apakah fenotip bagi progeni Q? [1 markah]

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(b) Apakah nisbah jangkaan pokok dengan biji berkedut kepada pokok dengan biji licin bagi

generasi F2? [1 markah]

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(c) Dengan menggunakan nisbah jangkaan pada (b), tentukan bilangan jangkaan fenotip generasi
F2.

Fenotip Bilangan cerapan Bilangan jangkaan
Berkedut 59
Licin 191

[2 marks]

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(d) Using the chi-square formula, determine the chi-square value for F2 generation. [3 marks]

(e) Chi-square (χ2) values at 5% level is given below. [4 marks]

Degree of freedom 5% level

1 3.841
2 5.991
3 7.815
4 9.488
5 11.070
6 12.592
7 14.067
8 15.507
9 16.919
10 18.307

Using the data from above table, explain whether the result obtained is in accordance with
Mendel’s first law.

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(f) Determine the dominant seed forms of pea plants. [1 mark]

Wrinkled: ...................................................................................................................................................

Smooth: ......................................................................................................................................................

(g) With the symbol R as dominant allele and symbol r as recessive allele, determine the

genotypes of both parents and progeny Q. [3 marks]

Female parent:...................................................................................................................................

Male parent: .....................................................................................................................................

Progeny Q: ........................................................................................................................................

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(d) Dengan menggunakan rumus khi kuasa dua, tentukan nilai khi kuasa dua bagi generasi F2.
[3 markah]

(e) Jadual nilai khi kuasa dua (χ2) pada aras 5% diberikan di bawah. [4 markah]

Darjah kebebasan Aras 5%

1 3.841
2 5.991
3 7.815
4 9.488
5 11.070
6 12.592
7 14.067
8 15.507
9 16.919
10 18.307

Dengan menggunakan data daripada jadual di atas, jelaskan sama ada keputusan yang diperoleh
mematuhi hukum Mendel pertama.

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(f) Tentukan kedominanan bentuk biji kacang pea. [1 markah]

Berkedut:....................................................................................................................................................

Licin: .........................................................................................................................................................

(g) Dengan simbol R sebagai alel dominan dan simbol r sebagai alel resesif, tentukan genotip

kedua-dua induk dan progeni Q. [3 markah]

Induk betina:..............................................................................................................................................

Induk jantan:..............................................................................................................................................

Progeni Q:..................................................................................................................................................

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