During hydrogenation of oils,higher melting point 'vegetable ghee' is formed because:

What is the ratio of $H$ to $O$ in the structure of fats?

Unsaturated fatty acids have

Consider the following four statements $(a-d)$ and select the option which includes all the correct ones only $:-$
$(a)$ Lipids are generally water insoluble.
$(b)$ The $R$ group could be a methyl $(-CH_3)$ or ethyl $(-C_2H_5)$ or higher number of $-CH_2$ groups ($1$ carbon to $19$ carbons) in fatty acids.
$(c)$ Palmitic acid has $16$ carbons including the carboxyl carbon.
$(d)$ Arachidonic acid has $21$ carbon atoms including the carboxyl carbon.

Which type of lipid forms a protective layer on the outer surface of the aerial parts of plants?

The component with the highest energy content is ...