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Question 1
1.1
DNA ü
1.2
1.3
(1)
a. Phosphate ü
b. Deoxyribose ü
c. Thymine/T ü
(3)
Nucleotide ü
(1)
(5)
Question 2
2.1
a. W – nucleotide ü
(2)
U – DNA ü
b. X – Phosphate ü
(2)
Y – deoxyribose ü
2.2
c. Z – hydrogen ü
(1)
d. V - Adenine ü
(1)
Nucleus
(1)
(7)
ü
Question 3
3.1
3.2
The DNA molecule unwinds ü
Hydrogen bonds between the strands break ü /the molecule unzips
Each strand serves as a template ü
Free DNA nucleotides ü in the nucleoplasm
Attach to their complementary bases ü on each template strand
Two genetically identical DNA strands are formed ü
These processes are controlled by enzymes ü
(6)
If the incorrect nitrogen base ü attaches to the original strand / if a base is added or
deleted
The sequence of the bases change ü on the DNA molecule
Resulting in a change in the gene structure ü
(2)
(8)
Life Sciences
[Insert Chapter name]
All Rights Reserved.
-3-
Question 4
4.1
The process where a person / organism’s DNA is mapped ü
DNA sequence of an organism /person is determined, or a bar code pattern is created.
4.2
The suspect could have been framed ü DNA could have been planted at the scene, or
Specimens could have been swopped at the lab. ü
Human error in the profiling process ü
Suspect could have in identical twin ü
The DNA was to the scene before the crime was committed. ü
Question 5
(1)
(4)
(5)
5.1
3ü
(1)
5.2
ATG ü
(1)
5.3
It determines the codes ü for the sequence of amino acids ü which determines the
type of protein. ü
(2)
5.4
a. AUG ü
(1)
b.
•
•
•
•
tRNA picks up specific amino acid ü
its anticodon ü matched the codon of the mRNA strand
amino acids will be arranged in a specific sequence ü
to form a specific polypeptide /protein ü
Question 6
Any
(3)
(8)
6.1
A – transcription
B – translation
(1)
(1)
6.2
C – ribosome
(1)
6.3
•
•
•
•
•
•
•
©
process is transcription ü*
free RNA nucleotides ü from the nucleoplasm ü
arrange according the base sequence ü of the DNA template
they are complimentary ü
A – U ü and C – G ü
Sugar phosphate bonds form ü between nucleotides to form the necessary
mRNA molecule
This process is controlled by enzymes ü
Any
(6)
(9)
-4-
Question 7
7.1
2 ü
(1)
7.2
CUC
7.3
a. TGG ü
(1)
ü
b. Aspartate ü
7.4
a.
Base ‘C’ was replaced by ‘U’ ü on the 4th codon
OR
th
ACG ü / the 4 codon, changed to AGU ü
(2)
ü / AGC
(2)
b.
7.5
©
•
•
it codes for the same amino acid ü / Serene
therefore there will be no effect ü / same protein will be formed
•
•
•
•
•
•
•
•
the process is transcription ü*
The double helix DNA molecule unwinds ü
The weak hydrogen bonds break ü
The DNA molecule unzips ü / two strands separate
One strand is used as a template ü to form mRNA
Using free RNA nucleotides ü in the nucleoplasm
The mRNA is complementary to the DNA strand ü / A-U, C-G
The process is controlled by enzymes ü
(2)
(6)
(14)