Given scientific fact as input, generate the question from this fact such that it can be answered from the input.

Ex Input:
You call egg-shaped galaxies, which are reddish to yellowish in color because they contain mostly old stars, elliptical galaxies.

Ex Output:
What do you call egg-shaped galaxies, which are reddish to yellowish in color because they contain mostly old stars?


Ex Input:
Momentum is directly related to both mass and velocity.

Ex Output:
Momentum is directly related to both mass and?


Ex Input:
Dermal cells type of cells make up the epidermis of a leaf.

Ex Output:

What type of cells make up the epidermis of a leaf?