Which of these describes a population? a. all the organisms that interact in a lake b. all the gray squirrels that live in a forest c. an area characterized by a group of plants and animals d. a nonliving factor in an organism’s environment is it b?

most community's take hundreds of years to become stable

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.