$A$ palaeontologist (a scientist who studies fossils) finds the fossil of an organism in a deeper layer of the Earth. What method will they use to estimate its age?

By what is the expression of tallness in the pea plant exhibited?

Which of the following is the correct match between List-$I$ and List-$II$?

List-$I$	List-$II$
$1$. Acquired trait	$a$. Wings of a bird and wings of a butterfly
$2$. Evidence of evolution	$b$. Wings of a bird and forelimb of a lizard
$3$. Homologous organs	$c$. Docked tail of a mouse
$4$. Analogous organs	$d$. Fossils

Which of the following is responsible for variation?

In pea plants, which trait is dominant between height and dwarfness?

Mendel crossed a pea plant having inflated green pod with a constricted yellow pod.
$(a)$ What type of a cross is it?
$(b)$ What type of plants are obtained in $F_{1}$ generation?
$(c)$ In $F_{2}$ generation the phenotype ratio is $9:3:3:1$. State the rule for the inheritance of traits observed by Mendel.