Question
How are target genes transferred to a bacterial cell?
A. Taq polymerase is used to cut the target gene, and ligase is used to attach it to a plasmid.
B. The target gene is amplified using PCR and then transferred to the bacterial cell using gel electrophoresis.
C. A nucleus containing the target gene is cloned and transferred into the bacterial cell.
D. The target gene and a plasmid are cut with the same restriction endonuclease and are attached using ligase.
▶️Answer/Explanation
Ans: D
Question
The diagrams show a virus and a bacterium.
Calculate the magnification of the bacterium.
[1]
a.
State the method that bacteria use to divide.
[1]
b.
Outline the effectiveness of antibiotics against viruses and bacteria.
[1]
c.
Saprotrophic organisms, such as Mucor species, are abundant in soils.
Define saprotrophic organisms.
[1]
d(i).
State one role of saprotrophic organisms in the ecosystem.
[1]
d(ii).
Answer/Explanation
Markscheme
45 000(x) or (x)45000 (accept answers in the range of 44000 to 46 000)
a.
binary fission
b.
effective against bacteria, but not viruses
c.
an organism that secretes enzymes in dead organic matter and absorbs its nutrients/products of digestion
d(i).
decomposer / recycle nutrients / break down organic material into inorganic material
Do not just accept “recycle” alone.
d(ii).