$$6\ \text{CO}_2 + 6\ \text{H}_2\text{O} \rightarrow C_6H_{12}O_6$ + 6\ \text{O}_2$$

$$C_6H_{12}O_6$ + 6\ \text{O}_2 \rightarrow 6\ \text{CO}_2 + 6\ \text{H}_2\text{O}$$

Question 1

Which process in the carbon cycle is responsible for converting atmospheric CO$$_2$$ into organic molecules within plants?

Accepted Answer

Photosynthesis

Question 2

In the nitrogen cycle, which process converts atmospheric nitrogen (N$$_2) $$into ammonia (NH$$_3) $$usable by plants?

Accepted Answer

Nitrogen fixation

Question 3

Which of the following is a major abiotic reservoir for phosphorus in the phosphorus cycle?

Accepted Answer

Sedimentary rocks

Question 4

A lake experiences a sudden increase in algae growth followed by a crash in oxygen levels. Which process is most likely responsible?

Accepted Answer

Eutrophication

Question 5

Which equation best represents the process of photosynthesis?

Accepted Answer

$$6\ 	ext{CO}_2 + 6\ 	ext{H}_2	ext{O} ightarrow C_6H_{12}O_6$ + 6\ 	ext{O}_2$$

Question 6

Which species is most likely to be considered a foundation species in a coastal ecosystem?

Accepted Answer

Giant kelp

Question 7

What is the primary difference between primary and secondary succession?

Accepted Answer

Primary succession occurs where soil has not previously existed; secondary succession occurs where soil is already present.

Question 8

Which of the following is an example of a keystone species?

Accepted Answer

Sea otter in a kelp forest

Question 9

Which process in the nitrogen cycle is the reverse of nitrogen fixation?

Accepted Answer

Denitrification

Question 10

Which human activity is most directly responsible for breaking the water cycle in forests?

Accepted Answer

Deforestation

Question 11

A poisonous fish species is introduced to a new ecosystem and rapidly spreads, outcompeting native species. This is an example of:

Accepted Answer

Invasive species

Question 12

Which of the following best describes the role of decomposers in biogeochemical cycles?

Accepted Answer

They break down dead material, returning nutrients to the soil and atmosphere.

Question 13

Which formula represents the conversion of ammonia to nitrate during nitrification?

Accepted Answer

$$NH_3$$ \rightarrow $$NO_2$$^- \rightarrow $$NO_3$$^-$$

Question 14

Why is biodiversity important for ecosystem resilience?

Accepted Answer

It allows ecosystems to better withstand environmental changes.

Question 15

Which of the following is NOT a direct driver of biodiversity loss?

Accepted Answer

Photosynthesis

Question 16

After a forest fire, grasses and perennials quickly colonize the area. This is an example of:

Accepted Answer

Secondary succession

Question 17

Which process in the phosphorus cycle returns phosphate to the abiotic reservoir?

Accepted Answer

Loss to ocean sediment

Question 18

Which equation best represents cellular respiration?

Accepted Answer

$$C_6H_{12}O_6$ + 6\ 	ext{O}_2 ightarrow 6\ 	ext{CO}_2 + 6\ 	ext{H}_2	ext{O}$$

Question 19

Which of the following is a consequence of deforestation?

Accepted Answer

Soil erosion

Question 20

A collapse in fish stocks due to overharvesting is an example of which human impact?

Accepted Answer

Overexploitation

Ecology: Cycles, Biodiversity, Succession, and Human Impact

Study Guide - Practice Questions