What is one difference between a cell wall and a cell membrane? 1) cell walls have gap junctions. cell membranes have plasmodesmata. 2) cell walls act as a boundary that nothing can pass through. cell membranes allow materials in and out of the cell. 3) cell walls are found inside the cell membrane. the cell membrane is the outermost structure of a cell. 4) cell walls are made of cellulose. cell membranes are made of proteins and phospholipids.

What were the main components of earth’s earliest atmosphere? oxygen and ammonia hydrogen and helium oxygen and nitrogen hydrogen and nitrogen

Hormones are chemical molecules produced by endocrine glands. one such endocrine gland is the thyroid gland, which synthesizes the thyroid hormone, which in turn affects the heart muscles. which two statements describe the probable reason for the function of the hormone? the cells in the heart have specific receptors that allow for the intake of hormones. the heart and the endocrine glands have the exact same types of cells. all cells make the same types of hormones. thyroid hormones show their effect on the heart by means of specialized cells. thyroid cells and cardiac cells have different dna.

The united states uses which source of energy to produce almost 40 percent of its electricity