What is the difference between Micro and prime lenses? (Nikon)?

I have seen that prime lenses like 35mm or 50mm can be used as portraits as well as extreme closeup shots?

Can we use micro lenses like 40mm or 60mm lens to take portraits?

Is it good to get a prime lens rather than micro lens because it takes both extreme closeup as well as good portraits?

I think you are confused - a conventional prime lens can't be used for extreme closeups without additional equipment (e.g.extension tubes).

A micro lens (especially the 60mm) can be used to take portraits. They cost a lot more than a typical 50mm 1.8G though.

A prime lens just means any fixed focal length lens.

A macro lens (a true macro) can close focus and render an image life size on the sensor (1:1 reproduction).

A macro lens is by definition a prime lens, but not all prime lenses are macro! In fact, most prime lenses do NOT allow the close focusing required for macro work.

Note: some zoom lenses (ie zoom between 2 focal lengths) are marketed as 'macro' lenses, but they are not true macro - they give a 2:1, 3:1 or 4:1 reproduction at best.

Some macro lenses are also of the ideal focal length for portraiture (you don't HAVE to use a macro close-up) - particularly the 50mm macro (Sigma), the 60mm macro (Nikon), the 100mm macro (Canon) and the 105mm macro (Nikon & Sigma).

I have a Sigma 50mm f2.8 macro - here are a macro shot taken with it & a portrait;

(macro)

(portrait)

So, the bottom line is you can use a macro lens for portrait AND macro, but you can only use a prime lens for portrait.

In Nikon talk "micro" means what everyone else calls "macro".

Macro lenses can be primes, but not all primes are macros.

50mm primes that are not macro lenses, can't be used for extreme close ups, at least not without extension tubes. A 60mm macro lens could be used for macro work, or for regular photography.

So the answer to your dilemma is to buy a 60mm Macro lens, and you can use it for both.