DENDROLOGY

Detailed explanation-1: -The gills are composed of three main parts: filaments, rakers, and arches. The arches are the structural component of the gill, rakers prevent debris from entering the fish through the gills, and the filaments absorb oxygen.

Detailed explanation-2: -Gills Many underwater animals, such as fishes and some kinds of worms, have gills. Gills are organs that remove oxygen from water. The internal structure of gills is an adaptation that enables two functions to happen: obtaining oxygen and eliminating the waste product called carbon dioxide.

Detailed explanation-3: -The external gill surface consists of apical plasma membranes of all uppermost cells. A glycocalyx is attached to those membranes. Glycocalyx is defined as a carbohydrate-rich layer that forms the outer coat of cells (Alberts et al., 2008).