In the given figure,what is the bond angle represented by '$a$' (in $^\circ$)?

The given figures represent the nitrogenous bases of nucleic acids. Identify the correct group.

Match the following:

$(a)$ Inhibitor of catabolic reaction	$(i)$ Ricin
$(b)$ Contains peptide bond	$(ii)$ Malonate
$(c)$ Cell wall material in fungi	$(iii)$ Chitin
$(d)$ Secondary metabolite	$(iv)$ Collagen

Select the correct option:

Deficiency of which vitamin causes loss of appetite,mental confusion,fatigue,and muscle depreciation?

In a water molecule,which bond connects the hydrogen and oxygen atoms?

Molecules are always moving. Some molecules move faster than others; . . . . . . is a measure of their average velocity of movement.