Answer:
Chitin.
Explanation:
The structure that is not a component of wall of sponges is Chitin. Their body comprise of calcareous or siliceous spicules or protein spongin fibres. Choanocytes are the distinctive cells located in the interior body walls of sponges. Sponges are similar to other animals in many characteristics such as they are multicellular, heterotrophic, lack cell walls and produce sperm cells in order to produce offspring sexually and also different from animals due to lack of tissues and organs.
A three-dimensional network consisting of extracellular macromolecules and minerals, such as collagen, enzymes, glycoproteins and hydroxyapatite that provide structural and biochemical support to surrounding cells.
Answer:4,500
Explanation:6mm times 750 equals 4,500
The correct answer is B. Stomata