Answer:
I wasn't quite sure what virus you were referring to in your question, but here's a general answer: Viruses use their host cells' machinery to replicate themselves.
If they are a specific type of virus known as a retrovirus, they have the ability to use the host cells' enzymes to change the RNA contained within the virus into DNA (via some type of replication I suppose).
In other cases, if they contain DNA instead of RNA (that is, the virus), they can use the host cell's machinery to create RNA via enzymes involved in transcription and/or they can incorporate that DNA into the host cell's DNA. This is part of a type of viral replication cycle known as the lysogenic cycle.
In another type of viral replication cycle known as the lytic cycle, the virus simply has itself and its genome duplicated until the host cell bursts, releasing the viral material. Here, again, the virus uses the host cell's machinery to replicate itself.
Answer:
Phenylketonuria, Cystic Fibrosis and Sickle Cell Anemia, these all are disorders caused by hereditary mutation.
Hope it helps!
Answer:
b. The two bacterial strains have different phenotypes.
Explanation:
In genetics, the trait that is expressed is often referred to as the dominant trait and it can also be expresssed phenotypically.
Since one of the bacteria produces the inducer, it therefore means that bacteria has the dominant strain for the regulatory inducer while the other bacteria might have the strain but since it is not expressed phenotypically, it is as a result not dominant.
Phenotype refers to the physical appearance of an organism as a result of the interaction of its genes with the environment. Examples of phenotypic expresssions are hair colour, skin colour, height, etc.
Answer:
Question: Two requirements for gas exchange which are accomplished by the gills in a fish include:
1. Water flowing in opposite directions across the gill lamellae for gas exchange, in other words, respiration is experienced by the fish.
2. The fish allows water through its mouth, then forces the water to drain through the gills supporting gill lamellae, and enhancing gas exchange.
Question: How does their structure help to satisfy these requirements?
1. The rows of gill filaments with numerous folds through diffusion makes sure oxygen from the water moves from a place of more concentration to the blood of the fish which has less concentration causing the removal of carbon dioxide.
2. The large surface area of the gill means it has to maximize the low percentage of dissolved oxygen in the water compared to the higher percentage of oxygen in the air makes it possible for water to pass through the mouth and empty through the gills after the mouth is closed.
