Variations within a species are an important part of Charles Darwin's theory of evolution. Which example can be explained by individual variation? The food source in a lake is not enough to support the bass population, but it can support the trout.
A population of brown bears has doubled in the past 10 years as its habitat size has increased.
Owls and foxes compete fiercely against each other for small rodents in their habitat.
Brightly colored cardinals are better able to survive and to reproduce than darker cardinals.

Which of the following statements is correct in hour our immune system responds to a potential pathogen? a. the adapted immune system will call on the innate immune system to destroy the pathogen. b. b cells will start reading the antigen code immediately and call t cells to assist in destroying the pathogen. c. the skin will be the first line of defense, and then the many phagocytes in the bloodstream will attempt to consume the possible pathogen. d. the t-cells in the adapted immune systems are the first to recognize the pathogen vaccines are weakened forms of disease causing microorganisms, which are given to patients to prevent disease. after the vaccine is administered, the immune system responds by creating a(n) to recognize the a. antigen, antibody b. antibody, antigen c. antibody, antibiotic d. antibiotic, antibody