Which type of nutrition is present in tapeworm?

Name the following with reference to the alimentary canal:
$(a)$ $(i)$ The largest gland.
$(ii)$ The gland that secretes digestive enzymes as well as hormones.
$(iii)$ The part where digested food is absorbed.
$(b)$ What are villi? Mention their function.

Choose the forms in which most plants absorb nitrogen.
$(i)$ Proteins
$(ii)$ Nitrates and Nitrites
$(iii)$ Urea
$(iv)$ Atmospheric nitrogen

Which is the correct sequence of air passage during inhalation?

$(a)$ Name the hormone which is released into the blood when its sugar level rises. Name the organ which produces this hormone and its effect on blood sugar level. Also,mention the digestive enzymes secreted by this organ with one function of each.
$(b)$ Explain the need for chemical communication in multicellular organisms.

Kidneys are located in the thoracic cavity, one on either side of the backbone.