2007-01-28 05:08:17 · 4 answers · asked by AJ 3 in Education & Reference ➔ Homework Help
Red blood cells carry oxygen throughout the body. Your body uses a lot of oxygen for cellular respiration (making energy). That is why you need so many.
2007-01-28 05:12:50 · answer #1 · answered by citrus punch 4 · 0⤊ 0⤋
Each red blood cell is so tiny that it slips through the capillaries in single file. Each can't carry much oxygen, so it takes a lot of them. And red blood cells don't contain nuclei, so they have short lifespans. The body is always replacing the older ones.
2007-01-28 05:11:48 · answer #2 · answered by ecolink 7 · 0⤊ 0⤋
because red blood cells are used to carry oxygen to every cell in your body to keep it alive. every cell requires oxygen, and your heart pumps millions of red blood cells filled with that from your lungs and back
2007-01-28 05:14:13 · answer #3 · answered by Michael 2 · 0⤊ 0⤋
A human body need many cells to keep your body moving or else we'd be dead.
2007-01-28 05:23:46 · answer #4 · answered by Country Girl 2 · 0⤊ 0⤋