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My name is Poon Cheng Moh. I have been teaching biology in SMK(P) Raja Zarina, Port Klang for 26 years. I sincerely hope that this blog on SPM Biology will be useful to both teachers and students.

Sunday, September 9, 2012

Answer to Hands on Pg 77-81


Objective Questions
1
A
9
D
2
C
10
D
3
D
11
C
4
B
12
C
5
A
13
D
6
A
14
A
7
C
15
B
8
D



Section A / Bahagian A
1. (a) (i) Genetic factor
(ii) Various alignments of homologous chromosomes during metaphase together
with crossing over during prophase I produce different combinations of alleles in gametes.
(b)(i) Draw a bar chart
(ii) Discontinuous variation
(iii) No intermediate values among individuals, discrete distribution
(c) Thumbprints, blood groups
(d) The graph of the heights of students shows normal distribution whereas the graph of the presence of dimples shows discrete distribution. There are no intermediate values in the graph of the characteristic of dimples whereas there are no clear cut values for the range of values of students’ heights.

2. a (i)
Lengths (mm)
Number of earthworms
50-53
2
54-57
5
58-61
8
62-65
10
66-69
9
70-73
7
74-77
4
78-81
1

(ii) Draw a histogram
(b) (i) Continuous variation
(ii) There are intermediate values
(iii) Mass of earthworms, size of earthworm
(c) (i) Earthworm in container P has the fastest growth rate.
(ii) Environmental factors such as types of soil and the presence of light affect the growth of earthworms.