True.
Nitrogen-fixing bacteria, microorganisms capable of transforming atmospheric nitrogen into fixed nitrogen (inorganic compounds usable by plants). More than 90 percent of all nitrogen fixation is effected by these organisms, which thus play an important role in the nitrogen cycle.
Internal means its on the inside
external means its on the outside
so an internal regulator is when the proteins respond to events on the inside of a cell
and an external regulator is when the proteins respond to events outside the cell
Caloric restriction in animals have been shown to R.ETARD AGING AND TO EXTEND LIFE SPAN.
Various research studies have shown that overeating shorten life span while reduce caloric intake r.etard aging and extends life span. In animal study, it has been shown that calorific restriction makes animals to live longer.
Answer :
based on the use of anatomical and genetic evidence to establish ancestral relationships
Explanation :
We know that,
The cladistic approach to primate :
The cladistic approach to primate is defined as phenotypically and anatomical characteristics, genetic and common characteristics that established ancestral relationships.
It is not purely based on phenotypes only, it required genetic and anatomic behaviour and evidences.
Hence, The correct answer is option (III)
If you don't have much of a reason it's just because you're a teenager, that's one of the symptoms :)
(really though, scientifically)