TASK DEFINITION: You are given a sentence and your task is to generate another sentence that supports the given input.
PROBLEM: A mitochondrion contains two main membranes composed of phosopholipid bilayers and proteins -

SOLUTION: Two membranes form the mitochondrion structure of a cell.

PROBLEM: A linkage is a relationship between genes that tends to cause the characteristics of these genes to be inherited together.

SOLUTION: Certain characteristics are frequently inherited together because of linkage.

PROBLEM: 1) Each sperm has a head (nucleus and acrosome), midpiece (mitochondria), and tail (microtubules).

SOLUTION:
The head of the sperm contains the nucleus.