I am not sure about the second one, but I know the first one.
The answer is D.
"An irregular galaxy is a galaxy that does not have a distinct regular shape, unlike a spiral or an elliptical galaxy. Irregular galaxies do not fall into any of the regular classes of the Hubble sequence, and they are often chaotic in appearance, with neither a nuclear bulge nor any trace of spiral arm structure."
Answer: D
Carbolic reactions breaks larger substances to smaller ones.
Anabolic reactions forms larger compounds from smaller units.
DNA synthesis does not involve breaking down of sugars.
Dehydration is a umbrella term used for reactions that releases water as a byproduct. In the case of sugars, they are held by Glycosidic bonds. To break them, hydration is needed as 1 water molecule breaks 1 glycosidic bond. The process of forming large units of sugars involves dehydration to form the glycosidic bonds. Therefore option d is wrong.
DNA guiding production of protein is definitely wrong as this process doesn't cause sugars to break down at all.
The answer is C. The brain stem controls blood circulation.
Cells with half the original number of chromosomes. So the answer is C.