Use the drop-down menus to complete the statements. are pure substances that cannot be broken down into a simpler form. are units of two or more atoms. are the smallest possible particles of an element. are pure substances made of two or more atoms of different elements.

a- all cells come from pre-existing cells

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.

the food storage products of chrysophytes are oils or the polysaccharide laminarin.   formerly classified as plants, the chrysophytes contain the photosynthetic pigments chlorophyll a and c all but the yellow-green algae also contain the carotenoid pigment fucoxanthin.