The first step would be to denture the starting solution that contains the DNA, enabling the DNA to separate into two strands.
The Atria Are the Heart's Entryways for Blood
The left atrium and right atrium are the two upper chambers of the heart. The left atrium receives oxygenated blood from the lungs. The right atrium receives deoxygenated blood returning from other parts of the body.
The heart
Answer:
D. They float on convection currents in the mantle.
Explanation:
The distinction between protostomes and deuterostomes is based on differences in their embryological development. Protostomes develop their oral end from their first developmental opening, while deuterostomes have their oral end develop from the second opening on the dorsal surface.
I believe it’s Precambrian.