Options for part A are as follows:
A) A mutation in the operator sequence
B) A mutation in the lac-Z gene
C) A mutation in the lac-Y gene
D) A super repressor mutation
Answer:
The correct answer:
Part a - A mutation in the operator sequence
Part b - It ensures that a cell dedicates resources to the production of enzymes involved in lactose metabolism only when lactose is available in the environment
Part C. true.
Explanation:
part a:
If there is a mutation in the operator sequence leads to prevent binding of the repressor which leads to allowing constitutive expression of the genes various conditions.
part b:
The biological role of the lac operon makes sure that the cell dedicates resources to the production of enzymes involved in lactose metabolism only when lactose is available in the environment
Part c:
RNA polymerase cannot transcribe the structural genes due to the repressor binds to the lac operator, therefore, the proper function of the lac operon is possible when the placement of the operator sequence between the promotor and the structural genes.
Answer:
Commensalism only occur among biotic factors
Explanation:
Abiotic factors are non-living factors that interacts with the biotic factor within an ecosystem. Commensalism is an association between two organisms in which one benefits and the other derives neither benefit nor harm.
From the above definition of commensalism, it is clear to note that it only involves two organisms rather than non-living organisms, hence; commensalism involves only biotic factors
Answer:
A. City A because there are no pollution sources upstream.
Explanation:
Water pollution is th contamination of water. There are many means through which water is contaminated such as industrial waste, agricultural waste and domestic waste et-cetra.
City A and City B get water from sunset lake and moth lake which have factories (industrial waste) and farmland (agricultural waste) nearby them, which are responsible for the contamination of river water. due to this cities can recieve contaminated water which can affect their health.
But the quality of water in City A will be best than that of City B because according to the image, City A do not have nay upstream soooooource of pollution, as factories and farmland are located at downstream.
Hence, the correct option is A.
The characteristic it shows is Growth
