What is an important chemical that contains
nitrogen which is vital for all living
things

Explain why phospholipid molecules form a bilayer. (3 marks)

Amale bird-of-paradise uses a dance to attract mates in which it flaps its tail feathers on the ground and jumps around a potential female mate. a different male bird-of-paradise does a similar dance but it jumps around the female in the opposite direction. the female bird is only attracted to one style of dance, in one direction.

If a checkpoint detects damaged dna, the checkpoint may