Number of histone proteins in each nucleosome core is

Some important events in the human female reproductive cycle are given below. Arrange the events in a proper sequence.
$A-$ Secretion of $FSH,$

$B-$Growth of corpus luteum,
$\mathrm{C}-$ Growth of the follicle and oogenesis,

$D-$ Ovulation,
$\mathrm{E}-$ Sudden increase in the levels of $\mathrm{LH}$

Given: $1=$ Natural selection; $2=$ Variations and their inheritance; $3=$ Survival of the fittest; $4=$ Struggle for existence. According to Darwinism, which of the following represents the correct sequence of events in the origin of new species?

There are two opposing views about origin of modern man. According to one view Homo erectus in Asia were the ancestors of modern man. A study of variation of DNA however suggested African origin of modern man. What kind of observation on DNA variation could suggest this?

Heroin is extracted from

Study the given pedigree chart of a certain family and select the correct conclusion which can be drawn for the character.

A mixture containing DNA fragments, $A, B, C$ and $D$ with molecular weights of $A+B=C, A>B$ and $D>\mathrm{C},$ was subjected to agarose gel electrophoresis. The positions of these fragments from cathode to anode sides of the gel would be

Which of the following representations shows the pyramid of number in a forest ecosystem?