insects don't breathe with lungs but humans do
Absolutely not
I need to find similes for the skeletal system. What is a simile for the respiratory system?
the stupid man who answered is the man for your task, the guy that won't die, deadpool
the stupid man who answered is the man for your task, the guy that won't die, deadpool
i dnt knw man
sperm cell
yes there are insects still unknown to man
Some insects are good for keeping crops healthy and thus are beneficial to man instead of using pesticides to get rid of annyoing insects, certain insects acutally eat those annyoing insects
Not likely, it is part of the digestive system, not the respiratory system. It is theorized however that it may have been there to digest grasses when man was a vegetarian only.
Lungs.
Well, it depends on the organism an the requirement. If you talk about lower organisms like poriferans they don't have circulatory system, respiratory system neither digestive system, simple diffusion occurs in their body as they do not need such system because of their environment and simplicity of development. If you consider flat worms (platyhelminthes) they have a low digestive system but lack any circulatory system as their cells are enogh close to the environment simple diffusion fulfills the respiratory requirement. The need, importance and significance increases with the complexity of an orgnism. As the man is most complex each system is really important. Without digestive system you can't make food simple,without respiratory system you can't yield energy, without circulatory system you can't supply energy or nutrients to the cells at distances. Hope you've got the answer of the question :)
yes