Answer:
The structure labeled A is the substrate. The enzyme is the black colored thingy on the bottom.
If hunted and sold, animals will have a lower chance of reproducing apart from not being there themselves, decreasing their population.
Having less species inhabiting an area, means less food for some predators. Which means that competition will occur among preators since food will be scarce.
Answer:

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Answer:
The frequency would be stable.
Explanation:
Based on the most common symptoms of cystic fibrosis, the disease only appears on adults and elderly. This feature means that the frequency of the disease would not drop or raise because they would still reproduce and pass the allele from generation to the next, maintaining the frequency stable.
Pros:
It is (mostly) based on pyrethrine spray which kills the
insects rapidly.
It not poisonous to other animals.
It uses synthetic, natural spray which is safe to use because
it breaks down within 10 minutes.
Te technique can reach tall forests.
It can be used in closed spaces ( greenhouses, basements
etc).
Cons:
It requires windless circumstances ( which is mostly at
nights).
Breathing fog may cause respiratory and throat irritation to
some.
Molecular Biology
This field of study deals with everything related to macromolecules, thus, what you will need for molecular biology would be something you could get proteins and nucleic acids from. Among the choices, the DNA of a pig and a calf would be the most helpful.
Comparative Anatomy
Comparative anatomy is a field of study that focuses on any similarities or differences between the anatomy or structure of different animals or species in general. Among the options, having the limb structure of a pig and a calf would allow you to practice the field since you have a structure to compare.
Developmental Biology
In this field, your concern would be how species grow and develop. For you to properly observe the growth and development, you must have the embryo of a pig and a calf. Therefore, among the options, this is the correct piece of evidence for this field.
IN SUMMARY:
Molecular Biology - Both DNA of a pig and a calf
Comparative Anatomy - Both limb structure of a pig and a calf
Developmental Biology - Embryo of a pig and a calf