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SECONDARY SCHOOL IMPROVEMENT
PROGRAMME (SSIP) 2014
GRADE 12
SUBJECT:
LIFE SCIENCES
LEARNER HOMEWORK SOLUTIONS
(Page 1 of 8)
© Gauteng Department of Education
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SESSION 5:
QUESTION 1:
P1
phenotype
genotype
Meiosis
Gametes
Brown x Grey
Bb
x bb
B, b
x b, b 
Fertilization
F1
genotype
Phenotype
OR
Bb ; bb 
2 brown, 2 grey
Gametes
B
b
b
Bb
bb
b
Bb
bb
1 mark for correct gametes
1 mark for correct genotypes
Allocation of marks
Showing the P1 (parents), G1 (gametes) and F1 (offspring) generation – 1 marks
Showing meiosis – 1 mark
Showing fertilization – 1 mark
Each correct step of problem – 5 mark
(8)
QUESTION 2:
QUESTION 3:
3.1.
XhY 
3.2
P1: XhY X XHXh 
Gametes: Xh Y XH Xh
F1: XHXh  XhXh  XHY  XhY 
50 %  probability of having haemophilia
(2)
(6)
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QUESTION 4:
4.1
4.2
4.3
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4.4
4.5
QUESTION 5:
5.1
5.2
5.3
© Gauteng Department of Education