test

Question 1

What is dissolved oxygen?

Answer 1

a measure of how much oxygen is dissolved in the water - the
amount of oxygen available to living aquatic organisms

Question 2

What is the equation for photosynthesis?

Answer 2

6CO2 + 6H2O ——> C6H12O6 + 6O2

Question 3

What is the equation for cellular respiration?

Answer 3

C6H12O6 + 6O2 ——————-> 6CO2 + 6H2O + ATP

Question 4

What are the end products of photosynthesis?

Answer 4

Glucose & oxygen

Question 5

What are the end products of cell
respiration?

Answer 5

Carbon dioxide, Water, ATP

Question 6

Why is dissolved oxygen in water important in aquatic ecosystems?

Answer 6

Respiration
Decomposition

Question 7

How does increased salinity affect the
concentration of dissolved oxygen in water?

Answer 7

The higher the salinity concentration the lower the oxygen.

Question 8

How does temperature affect the concentration of dissolved oxygen in water?

Answer 8

The higher the temperature – the lower the oxygen.

Question 9

What ways does oxygen get into the
water?

Answer 9

Photosynthesis
Atmosphere
Movement of Water

Question 10

In what ways does oxygen leave an aquatic ecosystem?

Answer 10

Atmosphere
Respiration
Decomposition

Question 11

Is dissolved oxygen bonded to any other
elements?

Answer 11

No, oxygen is not bonded to any other elements.

Question 12

Does the oxygen in water count as dissolved oxygen?

Answer 12

No, the oxygen in water does not count towards
dissolved oxygen.

Question 13

Which area of the water contains higher concentrations of oxygen top-closer to the surface or at the bottom?

Answer 13

The area of higher dissolved oxygen concentration
would be at the top – closer to the surface.

Question 14

What type of aquatic organisms need the
most dissolved oxygen? The least?

Answer 14

Organisms, such as fish, that live closer to the surface need the higher
dissolved oxygen concentration.

Organisms such as crabs and clams that live at the ocean floor would
require less dissolved oxygen concentration.

Question 15

What are 3 types of producers or autotrophs
you would find in an aquatic ecosystem?

Answer 15

Phytoplankton
Algae
Seaweed

Question 16

What time of day would there be increased
levels of dissolved oxygen in the water? Why?

Answer 16

Dissolved oxygen concentration would be greater through the
afternoon when the sun is at its peak.

More sun=higher rates of photosynthesis=increased oxygen.

Question 17

About how much less dissolved oxygen
does saltwater hold versus freshwater?

Answer 17

20%

Question 18

Where does decomposition take place –near the surface or at the bottom?

Answer 18

at the bottom (bacteria and fungi)

Question 19

What is eutrophication?

Answer 19

the process by which a body of water becomes enriched in dissolved nutrients (such as phosphates and nitrates) that stimulate the growth of aquatic plant life
usually resulting in the depletion of dissolved oxygen

Question 20

What are the two chemicals that are
responsible for the eutrophication of aquatic
ecosystems?

Answer 20

nitrates & phosphates

Question 21

How do these chemicals (nitrates & phosphates) get into aquatic ecosystems?

Answer 21

runoff & sewage waste

Question 22

What lake was discussed in the video?

Answer 22

Erie

Question 23

6 stages of eutrophication

Answer 23

addition of nitrates, growth of plants, death of plants, growth of bacteria, lack of oxygen, suffocation

Question 24

What is the immediate effect of the introduction of chemicals that cause eutrophication in an ocean, river, or lake?

Answer 24

The immediate effect is an increase in aquatic plant life, due to the increase in nutrients.

Question 25

Describe a lake that is affected by eutrophication.

Answer 25

Water would be murky with a thick mat of algae at the surface. Low to no aquatic animals.

Question 26

Define the term anoxia.

Answer 26

Little to no oxygen in water.

Question 27

Why does the rate of photosynthesis decrease over time in a eutrophic lake?

Answer 27

The rate of photosynthesis decreases due to the thick mat of algae that develops at the surface – does not allow photosynthesis to occur in aquatic plants at bottom.