A. <span>Exposure to an antigen
Exposure to viruses and antigens led to the foundation of modern vaccination. Vaccination introduces an antigenic material that helps the ability of the immune system to adapt a specific pathogen, therefore leading to a long-term immunity.</span>
Answer: genetic variation
Answer:
Mendel stated that each individual has two alleles for each trait, one from each parent. Thus, he formed the “first rule”, the Law of Segregation, which states individuals possess two alleles and a parent passes only one allele to his/her offspring. One allele is given by the female parent and the other is given by the male parent.
Explanation:
Answer:
Sunlight, Carbon dioxide, chlorophyll, and water are needed for photosynthesis to be carried out.
Explanation:
These 4 elements are essential to photosynthesis since they each allow the plant to grow and sustain homeostasis.
