AP BIOLOGY

Detailed explanation-1: -Mammals, reptiles, birds, fish and amphibians are vertebrates with endoskeletons (skeletons inside their bodies). Their skeletons provide support and protection and help them to move. Insects, spiders and shellfish are some of the invertebrates that have exoskeletons.

Detailed explanation-2: -In organisms like cow the skeleton is present inside the body. This is called endoskeleton. Organisms like tortoise and crocodile posses both exoskeleton and endoskeleton. Tortoise has an outer hard shell and a skeleton inside the body.

Detailed explanation-3: -All vertebrates have an endoskeleton. However invertebrates can be divided again between those with an exoskeleton and those with a hydrostatic skeleton.

Detailed explanation-4: -Some examples of endoskeleton are cartilage, bone, etc. The hard part present outside the body which protects the soft tissues and muscles is called the exoskeleton. It is developed from ectoderm and is mostly called a non-living structure.