It is spring and a little boy has terrible allergies. His nose is stuffed with mucus and he has a cough. Why are his mucous membranes producing so much mucus? He is allergic to mucus.
It is a sign that he has a head injury.
Mucus traps pollen so it cannot enter the body.
Mucous membranes always make more mucus in spring.

answer: 4

explanation: 8

there are mainly three domains in biological classification namely; archaea, bacteria, and eukarya.

archaea includes all the prokaryotic cells which are characterized by their lipid membranes. they have branched hydrocarbon which is attached to glycerol through an ether linkage.

bacteria includes all the prokaryotic cells, the cell membrane of which are made up of the unbranched fatty acid chain. in addition, they are attached to glycerol through an ester bond.

eukarya includes all the eukaryotic cells, that is, the cells contain a nucleus and other membrane-bound cell organelles.

they can be autotrophic as well as heterotrophic, unicellular as well as multicellular

they include kingdoms like protista, plantae, animalia, fungi et cetera.

read more on -

explanation: