This is the normal nucleotide sequence on a dna strand: a-c-t-g-g-a-t what is a substitution?

(a.) a-c-t-g-c-g-a-t

(b.) a-c-t-g-a-t

(c.) a-g-t-g-g-a-t

(d.) a-c-u-g-g-a-u

The correct answer is -

(C.) A-G-T-G-G-A-T.

Substitution is a type of point mutation (a permanent change in the nucleotide sequence of DNA when one nucleotide base sequence is substituted by another base).

In this question, Cytosine (C) at second position is substituted by Guanine (G) only in option C).

Thus, option C) is the right answer.

vote read

explanation:

plate tectonics and volcanic euptions

over time, plate tectonic processes cause continents to move to different positions on the globe.

for example, britain was near to the equator 300 million years ago, and therefore was hotter than it is today. for further details look at our climate through time poster or online map.

the movement of the plates also causes volcanoes and mountains to form and these too can contribute to a change in climate.

mountain ranges formed by plate tectonics. large mountain chains can influence the circulation of air around the globe, and consequently influence the climate.   warm air might be deflected somewhere cooler by the mountains.

it will increase due to the time span