Answer:
In biology, evolution is the change in the characteristics of a species over several generations and relies on the process of natural selection. The theory of evolution is based on the idea that all species? are related and gradually change over time.
<em>The function of skeletal muscles is to control the movement of internal organs. The skeletal muscle pulls the tendons attached to the bones.</em>
Answer:
In the human adult, the bone marrow produces all of the red blood cells, 60–70 percent of the white cells (i.e., the granulocytes), and all of the platelets. The lymphatic tissues, particularly the thymus, the spleen, and the lymph nodes, produce the lymphocytes (comprising 20–30 percent of the white cells).
Designing efficacious norovirus vaccines remains a major challenge due to several factors:
(1) the extreme genetic variability within the norovirus family and within genogroups
(2) the rapid evolution of antigenically dissimilar pandemic GII.4 norovirus strains
(3) the lack of lasting immunity upon natural exposure to noroviruses in at least a proportion of the population.
