Not all members of a species are the same. Every species exhibits (blank) . For example, some beetles are green, while others are brown.

Not all individuals in a population will survive to reproduce. Those that do, pass their (blank)
to their offspring.

when you breathe in, or inhale, your diaphragm contracts (tightens) and moves downward. this increases the space in your chest cavity, into which your lungs expand. the intercostal muscles between your ribs also enlarge the chest cavity. they contract to pull your rib cage both upward and outward when you inhale.