Q: Which of the following equations correctly represents the overall process of photosynthesis?

$$6\ \mathrm{CO}_2 + 6\ \mathrm{H}_2\mathrm{O} + \text{light energy} \rightarrow \mathrm{C}_6\mathrm{H}_{12}\mathrm{O}_6 + 6\ \mathrm{O}_2$$

Question 1

Which of the following best describes the primary function of stomata in plant leaves?

Accepted Answer

To allow the exchange of gases, specifically the intake of CO$$_2$$ and release of O$$_2$$

Question 2

On a hot, dry day, what is the most likely effect of closed stomata on the internal environment of a C3 plant leaf?

Accepted Answer

Increased O$$_2$$ concentration and decreased CO$$_2$$ concentration

Question 3

Photorespiration occurs when Rubisco binds to which molecule instead of CO$$_2$$?

Accepted Answer

O$$_2$$

Question 4

Which of the following is a direct consequence of photorespiration in C3 plants?

Accepted Answer

Release of CO$$_2$$ and consumption of ATP

Question 5

How do C4 plants minimize photorespiration?

Accepted Answer

By spatially separating carbon fixation and the Calvin cycle

Question 6

Which of the following is a characteristic of CAM plants that helps them avoid photorespiration?

Accepted Answer

Temporal separation of carbon fixation and the Calvin cycle

Question 7

Which of the following plants is an example of a CAM plant?

Accepted Answer

Pineapple

Question 8

Which of the following statements about C4 and CAM plants is TRUE?

Accepted Answer

C4 plants use spatial separation, while CAM plants use temporal separation to avoid photorespiration

Question 9

What is the main ecological role of autotrophs in the biosphere?

Accepted Answer

They produce organic compounds from CO$$_2$$ and other inorganic substances

Question 10

Van Niel’s hypothesis about the source of oxygen produced during photosynthesis was confirmed by experiments using labeled oxygen. Which molecule, when labeled, resulted in labeled oxygen gas being produced?

Accepted Answer

H$$_2O$$

Question 11

Which of the following equations correctly represents the overall process of photosynthesis?

Accepted Answer

$$6\ \mathrm{CO}_2 + 6\ \mathrm{H}_2\mathrm{O} + 	ext{light energy} ightarrow \mathrm{C}_6\mathrm{H}_{12}\mathrm{O}_6 + 6\ \mathrm{O}_2$$

Question 12

A scientist is studying a plant that opens its stomata at night and closes them during the day. Which type of plant is this, and what advantage does this adaptation provide?

Accepted Answer

CAM plant; reduces water loss and avoids photorespiration

Question 13

Which of the following best explains why C4 plants are able to fix CO$$_2$$ even at low concentrations of CO$$_2$$ and high concentrations of O$$_2$$?

Accepted Answer

They use PEP carboxylase for initial CO$$_2$$ fixation, which has a higher affinity for CO$$_2$$ than Rubisco

Question 14

Which of the following statements about heterotrophs is correct?

Accepted Answer

They depend on autotrophs for food and oxygen

Question 15

A plant scientist labels the oxygen in CO$$_2$$ and H$$_2O $$separately and tracks the fate of the labeled oxygen during photosynthesis. What result would confirm Van Niel’s hypothesis?

Accepted Answer

Labeled oxygen from H$$_2O is $$found in the O$$_2$$ gas produced

Question 16

Which of the following is a correct comparison between photoautotrophs and chemoautotrophs?

Accepted Answer

Photoautotrophs use light as an energy source, while chemoautotrophs use chemical compounds

Question 17

A C3 plant is exposed to hot, dry conditions. Predict the effect on its sugar production and explain why.

Accepted Answer

Sugar production decreases because stomata close, reducing CO$$_2$$ availability and increasing photorespiration

Question 18

Which of the following best describes the process of photorespiration?

Accepted Answer

A process in which Rubisco adds O$$_2$$ instead of CO$$_2 to $$the Calvin cycle, leading to the release of CO$$_2$$ and consumption of ATP

Question 19

Which of the following is NOT a strategy used by plants to avoid photorespiration?

Accepted Answer

Using Rubisco exclusively for carbon fixation

Lecture 17

Guida di studio - Domande di pratica

Study guide - Flashcard