Given a scientific passage and an answer, generate a question for the given answer.

Passage: Endoskeleton An endoskeleton is a skeleton that consists of hard, mineralized structures located within the soft tissue of organisms. An example of a primitive endoskeletal structure is the spicules of sponges. The bones of vertebrates are composed of tissues, whereas sponges have no true tissues (Figure 38.4). Endoskeletons provide support for the body, protect internal organs, and allow for movement through contraction of muscles attached to the skeleton. Answer: endoskeleton
A skeleton that consists of hard, mineralized structures located within the soft tissue of organisms is called what?

Passage: The mass number is the number of protons plus the number of neutrons in an atom. For example, most atoms of helium have 2 neutrons, so their mass number is 2 + 2 = 4. This mass number means that an atom of helium has a mass of about 4 amu. Answer: protons and neutrons
What makes up the mass number of an atom?

Passage: An internal skeleton. The internal skeleton supports the animal, protects internal organs, and allows for movement. Answer: internal
Which type of skeleton supports the animal, protects internal organs, and allows for movement?