Hormones are any member of a class of signaling molecules in multicellular organisms, the job of hormones in a body is to be messengers and controlling and corddinating things in the body peptide hormones is the molecular structure of hormones . Amino acids is what they are composed of. The ovaries and the testes are organs that produce hormones
Bones are made up of Calcium Phosphate given by the chemical formula, 
. When bones are kept in Hydrochloric acid, given by the chemical formula, HCl, they become soft because the calcium compound present in the bones changes its form. The following double displacement reaction takes place when the bones are kept in HCl,
---> 
Calcium chloride is water soluble, and gets washed away. This makes the bone thin and soft.
B: nucleus, mitochondria, cell membrane
c and d both have chloroplasts which are unique to plant cells
a is wrong because only plant cells have cell walls
Mannan-oligosaccharides (MOS) are prebiotics composed of complex carbohydrate molecules, derived from the outer cell wall of S. cerevisiae, whose main components, β-glucans (mannoproteins), are known as elements capable of activating the immune system of animals [3, 5]. :D
