Study the bohr model shown below.

what group this element part of?

1. group 1a

2. group 2a

3. group 3a

4. group 4a

5. group 5a

Although respiratory organs vary across different organisms, they all contain respiratory surfaces that have a large surface area and are extremely thin. explain why having an extremely thin respiratory surface with a large surface area is advantageous for the process of gas exchange