Answer:
A. humans going underwater and exhaling
Explanation:
The dissolved oxygen in water refers to the amount of oxygen that is found in water. However, there are various ways that oxygen dissolves in a body of water, these includes;
- Photosynthesis of aquatic plants: Oxygen is the waste product of the photosynthetic process carried out by green plants. Hence, when aquatic plants undergo photosynthesis, oxygen from them tend to dissolve into water.
- Diffusion from the atmosphere: Oxygen from air or atmosphere also dissolves in water
- aeration as water moves over rocks and debris, and from wind and waves
However, humans do not exhale oxygen but carbon dioxide, hence, it is not a source of dissolved oxygen
DNA replication
After the process of DNA replication occurs, each daughter cell receives an exact copy of the parent cell's DNA.
DNA replication is a biological process by which a DNA molecule divides to produce two copies of itself during cell division. DNA replication takes place in all living organisms. During DNA replication, an enzyme known as helicase separates the double helix structure of the DNA molecule into two separate strands which serve as templates for making the new strands of DNA.
Upwelling is a process in which cold water from depths arise to the surface,
it's important because :
- It bring a lot of nutrients to the surface of the ocean
- It maintain the temperature of the ocean
hope this helps
hellosphere. This is not an actual part of the "spheres" on Earth
Hope this helps
