Which of the following best describes why polar bears are a sub-species of brown bears instead of a completely separate species? A. Because they both have thick fur and 4 legs, so they are very similar B. Because they both live on the same continent, so they can’t be two separate species C. Because they can still breed in the wild. Once they no longer mate with brown bears, they will be considered a separate species D. All of the above

An organ system consists of a group of organs that performs specific functions necessary for the survival of an organism. humans have eleven different organ systems: integumentary, skeletal, muscular, nervous, endocrine, circulatory, lymphatic, respiratory, digestive, urinary, and reproductive. discuss the function of neurons, the brain and the spinal cord within the human nervous system while explaining the interrelationship of each organ.

What drives the atp synthase reactions that produce atp

Resperation is a way to release carbon back into the atmosphere