Dead Zone (Open Note Lab Grade) (2023)

2

What happens to the dissolved oxygen (the oxygen that is in the water) between May 1st and 15th based on the data in Figure 1.

The dissolved oxygen increased

The dissolved oxygen decreased

The dissolved oxygen stayed the same

There are two main ways oxygen gets dissolved in water. The first occurs when air mixes with water. More oxygen gets mixed in when the water is moving around a lot, when waves crash, or when water flows over rocks.

The second way oxygen gets into water is when it is released by producers such as underwater plants or other aquatic life that uses photosynthesis. Phytoplankton are single-celled organisms that add oxygen to water in this way, through photosynthesis.

2

Phytoplankton carry out photosynthesis. What do you think typically happens to the phytoplankton population in the spring, when solar energy to the Gulf of Mexico region increases after winter.

The phytoplankton increased

The phytoplankton decreased

The phytoplankton population remained the same

4

How is the phytoplankton population related to the oxygen concentration in Figure 1 (see the graph).

Phytoplankton perform

2

What do you think would happen to the concentration of carbon dioxide in the water during the same time period, May 1-15?

The carbon dioxide concentration will increase

The carbon dioxide concentration will decrease

The carbon dioxide concentration will stay the same

2

Describe what is happening to dissolved oxygen (oxygen in the water) between May 15th and 31st, based on the data in Figure 2.

Oxygen levels increased

Oxygen levels decreased

Oxygen levels stayed the same

2

4

Consumers and decomposers that eat the phytoplankton are also present In the Gulf of Mexico. As the phytoplankton population increases, so do the populations of consumers and decomposers. How might the presence of increased numbers of consumers and decomposers help explain the decrease in the oxygen concentration?
Be sure to mention the process that consumers perform.

4

From May 15 to May 31, the number of consumers and decomposers increased. What do you think would happen to the concentration of carbon dioxide in the water.

As the number of consumers and decomposers increase, the concentration of carbon dioxide

8

Make your model below OR make your model on paper.

1

Each phytoplankton only lives a few days. When they die, they sink to the bottom, where they are decomposed by bacteria. As more and more phytoplankton die and fall to the bottom, what do you expect happens to bacteria populations?

A. increase

B. decrease

C. stay the same

1

What process do decomposers (consumers) use to break down dead organisms in order to create energy.

A. Photosynthesis

B. Cellular respiration

The graph shows how concentrations of dissolved oxygen (O₂) and carbon dioxide (CO₂₎gases change in pond water on a warm, sunny day

2

Between 6 a.m. and 6 p.m., the rate of

Dead Zone (Open Note Lab Grade) (2023)

What happens to the dissolved oxygen (the oxygen that is in the water) between May 1st and 15th based on the data in Figure 1.

Phytoplankton carry out photosynthesis. What do you think typically happens to the phytoplankton population in the spring, when solar energy to the Gulf of Mexico region increases after winter.

What do you think would happen to the concentration of carbon dioxide in the water during the same time period, May 1-15?

Describe what is happening to dissolved oxygen (oxygen in the water) between May 15th and 31st, based on the data in Figure 2.

Make your model below OR make your model on paper.

Each phytoplankton only lives a few days. When they die, they sink to the bottom, where they are decomposed by bacteria. As more and more phytoplankton die and fall to the bottom, what do you expect happens to bacteria populations?

What process do decomposers (consumers) use to break down dead organisms in order to create energy.

What happens to the dissolved oxygen (the oxygen that is in the water) between May 1st and 15th based on the data in Figure 1.

Phytoplankton carry out photosynthesis. What do you think typically happens to the phytoplankton population in the spring, when solar energy to the Gulf of Mexico region increases after winter.

What do you think would happen to the concentration of carbon dioxide in the water during the same time period, May 1-15?

Describe what is happening to dissolved oxygen (oxygen in the water) between May 15th and 31st, based on the data in Figure 2.

What process did you predict was responsible for the decrease in dissolved oxygen.

Make your model below OR make your model on paper.

Each phytoplankton only lives a few days. When they die, they sink to the bottom, where they are decomposed by bacteria. As more and more phytoplankton die and fall to the bottom, what do you expect happens to bacteria populations?

What process do decomposers (consumers) use to break down dead organisms in order to create energy.

What process did you predict was responsible for the decrease in dissolved oxygen.