Answer:
a. antigen
Explanation:
The Immune system is composed of immune cells that defend the body against foreign substances such as bacteria or virus. Lymphocytes (B and T cells) are one of the main immune cells
Lymphocytes have the ability to recognize and bind to antigens, wich are substances foreign to the body ( i.e bacterial or virus elements) that evokes an immune response.
Answer:
Consumers must obtain their nutrients and energy by eating other organisms. Decomposers break down animal remains and wastes to get energy.
secondary consumer obtain their energy by eating or consuming primary consumers.
It is true but commonly called Richter meter
This is the structure of DNA and nucleotide is the phosphate group with sugar (the pink one ) and base that are 4 different bases : A, T, C, G and between these bases we have hydrogen bonds and you can see that always it like : C≡G
A=T :))) i hope that helps :)))https://www.google.com/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&cad=rja&uact=8&ved=0ahUKEwiawYOO7-...