Answer:
A = Activator
B = Effector
Explanation:
An activator is a protein which typically binds to a short (50–1500 bp) region of DNA which might be located either upstream (mainly) or downstream of a gene so as to cause increased transcription. This particular region of DNA is known as enhancer and activator is also known as transcription factor. Activator is a trans-acting factor which binds to the cis-acting factor which is enhancer so as to enhance transcriptional expression.
But another protein named as effector may restrict activator from binding to the enhancer leading to a decrease in transcriptional expression by binding to the activator allosterically. Allosteric binding of effector to the activator causes conformational change in activator so it can no longer bind the enhancer.
DNA is copied during mitosis and when the two resulting copies of DNA are compared they are found to contain the same order of nucleotides is not the result of mutation in the DNA sequence of an organism.
Explanation:
Mutation is the process
It is caused by certain chemicals called mutagens or by environmental factors.
In mutation the nucleotide get change which eventually changes the protein product.
In mutation purine base gets mutated to purine base and pyrimidine base gets mutated to pyrimidine only.
A single change in nucleotide is called point mutation and the effect occurring because of it is called frame shift mutations.
In S phase there are checkpoints which ensure that DNA replication is accurate and when mitosis follows it equal distribution of DNA takes place between the two daughter cells hence no mutation will takes place.
Yes, they are.
Minerals are the result of rock metamorphic cycles and other volcanic activities that result to these mixture of different minerals. Minerals can also be the cause of some biogeochemical cycles that occurs on the earth's different spheres.
Yes, waves can carry energy through
