Marking ! will mark brainliest answer provide the explanation's for the following terms - venus return - muscular pump - respiratory pump - gravity

Venus return is the rate of the blood flow that leads back to the heart. It usually normally limits cardiac output.

The pump is when your muscles will swell up during your workout, which is caused from the excessive amount of blood going into the muscle and filling it up the same way you would kinda fill up a water balloon.

A Respiratory Pump is one of those abdominal and thoracic structures that cause the expansion and contraction of the lungs.

Gravity is the phenomenon by which two bodies having mass are litarally just attracted to each other.  

Hope this helps:)

since you have not provided the options here i   am going to give you general overview about hormone.hormone are actually the part of endocrine system in our body and produced by the endocrine glands. the hormones act like a chemical messenger   within human body. once produce by the glands they   travel through the blood stream and reach at specific or target tissue and organs   which result in control of our body function. the hormones are specific in their work and work on only the targeted tissue or organ   . with the of hormone endocrine system regulate the heart rate , metabolism, our mood and   growth as well as the development and even the sleeping cycle etc. they actually are the messenger for body cell and organs .