Which statement is true of the adaptive, but not the innate, immune system? Choose 1
A. Many cells work together to coordinate the response.
B. It involves the use of lymphocytes.
C. It fights both viruses and bacteria.
D. The receptors are highly specific.

The table shows dates and appearance of index fossils. which rock layers can be dated most precisely? a) a layer containing both a fossil 4 and a fossil 3 b) a layer containing both a fossil 2 and a fossil 3 c) a layer containing both a fossil 1 and a fossil 4 d) a layer containing both a fossil 1 and a fossil 2

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

What do your cells need to live? a. carbon dioxide b. carbon c. air d. oxygen