The process of ovulation and menstruation in women and other female primates.
Transfer of energy from one living to another in a food chain is called pyramid energy.
So simply we can energy pyramid shows how much energy passes from one living to another in a food chain.
Food chain always begins with autotrophs i.e. green nature (plants). Which becomes producers.
There are different types of organisms based on food habits and their environment.
I think it’s proteins and nucleic acids