As the heart beats, it pumps blood through a system of blood vessels, called the circulatory system. The vessels are elastic, muscular tubes that carry blood to every part of the body.
Blood is essential. In addition to carrying oxygen from the lungs and nutrients to your body's tissues, it also takes the body's waste, including carbon dioxide, away from the tissues. This is necessary to sustain life and promote the health of all the body's tissues.
Plants are called producers because they make their own food. So the grass is the producer.
The answer is D has mitochondria and chloroplasts. In the leaf, so must have chloroplast, most eukaryotic cells have mitochondria (powerhouse of the cell)
