Darwin originally defined evolution as ( concept 19.1)

1. watermelon, papaya, oranges, bananas, and lemons are included in this food group. vitamin c 2. you need 6 or more servings of this food group each day vitamins d and a 3. found in fruit and keeps blood vessels healthy calcium 4. vitamins found in milk bread and grain 5. a mineral that strengthens bones fruit

Explain why it’s important for scientists to study the sun. list at least two challenges researchers face when examining earth’s nearest star.

Internal feedback works to maintain homeostasis when your a. heart rate decreases as your white blood cells increase b. breathing rate decreases as your red blood cells decrease c. heart rate increases as your liver is cleaning blood d. breathing rate increases as your heart rate increases