The pumping of the heart is tied to the respiratory system
<span>Large carnivores in general are often used as indicator species because of their seat at the top of the food chain. ... When a large carnivore is missing from an ecosystem this can
reflect problems in prey populations, usually caused by larger issues
such as over-harvest of game, presence of disease, or habitat changes.</span>
Carbohydrates- they are simple and burn quickly, giving you short but fast boosts of energy.
Oxygen is made and so is glucose (its actually sugar, but glucose is better sounding) by combining carbon dioxide and water using light energy as a source of energy. Also like to make sugars.
