The rate of cell growth is increasing,its takes about 20 hours to grow 10 ells ,but it only takes 2-3 hr to grow the last 20 cellsExtend your thinking: In living organisms, the cell cycle is closely regulated.
Answer:
a. Exoskeleton made of chitin
Explanation:
Arthropods are invertebrate animals with articulated locomotor organs, which is the main characteristic of this phylum. The articulated paws allow the animal to perform various movements, very well defined and elaborate. This feature gives these animals not only efficient locomotion, but also aids in their defense and food capture.
They have another striking feature as well, which is the diversely segmented body, but always covered by a chitin cuticle, which represents its exoskeleton. Some have a calcareous shell outside the chitinous exoskeleton, such as crustaceans.
