Answer: The DNA double helix is held together by two types of bonds,
covalent and hydrogen.
Explanation: Covalent bonds occur within each linear strand and strongly
bonds the bases, sugar and phosphate groups.
They are representatives between the extinction events
Answer:
Primary succession because you have to find the resources to be able to produce that succession. Hope that helps!
Answer:
Explanation:
El sistema inmune es una red compleja de células y proteínas que defiende al cuerpo contra las infecciones. El sistema inmune mantiene un registro de todos los gérmenes (microbios) que ha derrotado para poder reconocer y destruir el microbio rápidamente si ingresa nuevamente al cuerpo.