Differentiate between bone and cartilage with respect to structure,function and location.

Name the animal tissue which acts as a heat insulator.

$(a)$ Give reasons for the following:
$(i)$ Multicellular organisms are considered more efficient.
$(ii)$ Sclerenchyma cells have a narrow lumen.
$(iii)$ Epidermis is thicker in desert plants though it is usually single layered.
$(b)$ Name the following:
$(i)$ Tissue that occurs in specific regions of growth.
$(ii)$ Tissue present at the growing tips of stems and roots.
$(iii)$ Tissue at the base of the leaves or internodes on twigs.
$(iv)$ Basic packing tissue in the form of a few layers of cells.

State whether the following statement is true or false:
Epithelium covers most organs and cavities within the body.

Permanent tissues are derived from

Cartilage is not found in