B. some species die out when environmental changes occur
The ocean absorbs more co2
Mutations are caused by changes in nucleotide bases. these altered base formed different amino acid depending upon nucleotide base sequence that code specific amino acid. ... even though some mutations, can have a more effect on amino acid coding, which can affect what kind of proteins are produced.
Answer:
DNA replication is described as semi-conservative.
Explanation:
DNA replication is described as semi-conservative because each double helix formed comprises one strand from the helix from which it was copied and a new strand. That is, the replication of one helix results into two new copies of which each contains one of the original double stranded helix from which it was synthesized.
Answer:
Option D, A subject is observed both before and after two exposures to the treatment.
Explanation:
In A-B-A-B design the alphabets have following meaning
a) First A – It is the baseline value or the value measured before treatment
b) First B – It is the treatment measurement
c) Second A - It is the withdrawal of treatment
d) Second B – It is the reintroduction of treatment
The second A is known as the reversal phase in which the intervention is withdrawn to see if the target behavior returns to the baseline behaviour
Thus , there are two measurements involved one before the intervention and second after the intervention
Option D is correct
