D) The AV valves are supported by chordae tendineae so that they do not blow back up into the atria during ventricular contraction.
Answer:
I think it explains that the DNA molecules are double helix with alenine and thymine paired together
CO2 is considered organic because it doesn’t contain a hydrogen. Organic compounds must contain carbon bound to hydrogen and possibly other elements.
Levels<span> of </span>organization<span> in ecology include the population, community, ecosystem, and biosphere. An ecosystem is all the living things in an area interacting with all of the antibiotic parts of the </span>environment<span>.</span>