The pulmonary artery and its branches deliver blood rich in carbon dioxide (and lacking in oxygen) to the capillaries that surround the air sacs. The circulation of the blood through the lungs. The veins that return the oxygenated blood from the lungs to the left atrium of the heart.
The muscular system<span> is responsible for the movement of the human body. Attached to the bones of the </span>skeletal system<span> are about 700 named </span>muscles<span> that make up roughly half of a person's body weight. Each of these </span>muscles<span> is a discrete organ constructed of </span>skeletal muscle<span> tissue, blood vessels, tendons, and nerves.</span>
I know that B applies, and D might apply assuming it means certain materials can pass through and not all materials can pass through.
The correct answer is letter a. The body takes a lot of time and energy for our body to break down more complex foods, while simple foods are broken down more quickly and easily absorbed by the body. Complex foods contain more ingredients and more nutrients that are hard to be broken down, not like simple foods, such as candy or sugar that can be easily broken down by the body because of its simple structure.
