Aperson's skin cells and eye cells make different types of proteins to perform their functions. what is the source of the instructions from which all of the proteins are made?
(a) genes
(b) mitochondria
(c) ribosomes
(d) gametes

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.