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

Ex Input:
Passage: CHAPTER SUMMARY 38.1 Types of Skeletal Systems The three types of skeleton designs are hydrostatic skeletons, exoskeletons, and endoskeletons. A hydrostatic skeleton is formed by a fluid-filled compartment held under hydrostatic pressure; movement is created by the muscles producing pressure on the fluid. An exoskeleton is a hard external skeleton that protects the outer surface of an organism and enables movement through muscles attached on the inside. An endoskeleton is an internal skeleton composed of hard, mineralized tissue that also enables movement by attachment to muscles. The human skeleton is an endoskeleton that is composed of the axial and appendicular skeleton. The axial skeleton is composed of the bones of the skull, ossicles of the ear, hyoid bone, vertebral column, and ribcage. The skull consists of eight cranial bones and 14 facial bones. Six bones make up the ossicles of the middle ear, while the hyoid bone is located in the neck under the mandible. The vertebral column contains 26 bones, and it surrounds and protects the spinal cord. The thoracic cage consists of the sternum, ribs, thoracic vertebrae, and costal cartilages. The appendicular skeleton is made up of the limbs of the upper and lower limbs. The pectoral girdle is composed of the clavicles and the scapulae. The upper limb contains 30 bones in the arm, the forearm, and the hand. The pelvic girdle attaches the lower limbs to the axial skeleton. The lower limb includes the bones of the thigh, the leg, and the foot. Answer: endoskeleton

Ex Output:
Of the three types of skeleton designs - hydrostatic skeletons, exoskeletons, and endoskeletons - which do humans possess?

Ex Input:
Passage: The population is an important unit in ecology as well as other biological sciences. How is a population defined, and what are the strengths and weaknesses of this definition? Are there some species that at certain times or places are not in populations?. Answer: cell division

Ex Output:
During interphase, the cell undergoes normal growth processes while also preparing for what, by accumulating energy and building blocks of dna?

Ex Input:
Passage: This diagram represents the cell cycle in eukaryotes. The cell cycle depicts the life of an eukaryotic cell. The cell cycle has four phases: the first growth or gap (G 1 ) phase, the synthesis (S) phase, the second growth or gap (G 2 ) phase and the mitotic (M) phase. The M phase includes mitosis and cytokinesis. The cell spends the majority of the cycle in the first three phases (G 1 , S, G 2 ) of the cycle, collectively known as interphase. After cytokinesis, two genetically identical daughter cells are formed. Answer: four

Ex Output:
How many cycles do cells have?