Answer:
Forward chaining as the name suggests, start from the known facts and move forward by applying inference rules to extract more data, and it continues until it reaches the goal, whereas backward chaining starts from the goal, move backward by using inference rules to determine the facts that satisfy the goal.
Technically, they can but you don't have to be related because you can have things in common with another person with are personality traits , and if they have different skin colors it doesn't matter , and you can still have many traits in common , because my sister is darker than me a lot but we still share same traits.
A nucleus consists of a nuclear membrane that surrounds it, within the membrane there is a nucleolus which can be compared metaphorically to the yolk of an egg in appearance. The nucleolus is surrounded by nucleoplasm which is quite like the cytoplasm.
That's called Parasthesia.
