$$6CO_2 + 6H_2O + \text{Light energy} \rightarrow C_6H_{12}O_6$ + 6O_2$$

Question 1

Which of the following best describes the overall chemical equation for photosynthesis in plants?

Accepted Answer

$$6CO_2 + 6H_2O + 	ext{Light energy} ightarrow C_6H_{12}O_6$ + 6O_2$$

Question 2

During the light-dependent reactions of photosynthesis, what is the primary role of the electron transport chain (ETC)?

Accepted Answer

To move electrons from Photosystem II to Photosystem I, creating a proton gradient used to generate ATP

Question 3

Which enzyme catalyzes the first step of the Calvin Cycle, and what is its function?

Accepted Answer

RUBISCO; it catalyzes the reaction between $$CO_2$$ and ribulose-1,5-bisphosphate (RuBP) to form 3-phosphoglycerate (3-PGA)

Question 4

A plant is grown hydroponically in a solution lacking magnesium. Which of the following symptoms would you most likely observe?

Accepted Answer

Chlorosis (yellowing) of leaves due to impaired chlorophyll synthesis

Question 5

Why do plants require nitrogen-fixing bacteria in the soil?

Accepted Answer

Because atmospheric $$N_2 is $$inert and cannot be directly used by plants

Question 6

Which of the following best explains the pressure flow hypothesis for sugar transport in phloem?

Accepted Answer

Sucrose is actively loaded into phloem at the source, causing water to enter osmotically, increasing turgor pressure and driving sap toward sinks

Question 7

Which of the following is a macronutrient required by plants in relatively large quantities?

Accepted Answer

Potassium ($$K^+)$$

Question 8

A plant growing in phosphorus-deficient soil is likely to benefit most from which of the following adaptations?

Accepted Answer

Forming a symbiotic relationship with mycorrhizal fungi

Question 9

Which process in the nitrogen cycle converts ammonia ($$NH_3) $$into nitrite ($$NO_2$$^-$$) and then into nitrate (NO_3$^-$$)?

Accepted Answer

Nitrification

Question 10

Which of the following best describes the role of potassium in plant cells?

Accepted Answer

It acts as a major solute for osmotic balance and is a cofactor for many enzymes

Question 11

A scientist wants to determine if a mineral is essential for plant growth. Which experimental approach would be most appropriate?

Accepted Answer

Grow plants hydroponically in a solution lacking only the mineral in question and observe for deficiency symptoms

Question 12

Which of the following is a direct product of the light-dependent reactions of photosynthesis?

Accepted Answer

ATP

Question 13

Mixotrophic plants, such as Venus flytraps, are most likely to be found in which type of environment?

Accepted Answer

Nutrient-poor soils, especially those low in nitrogen

Question 14

Which of the following statements about micronutrients in plants is correct?

Accepted Answer

They are required in small quantities and often act as cofactors for enzymes

Question 15

Which of the following best explains why plants cannot use atmospheric nitrogen ($$N_2) $$directly?

Accepted Answer

$$N_2$$ has a strong triple bond, making it inert and unreactive

Question 16

Which of the following is a correct sequence of events in the pressure flow model of phloem transport?

Accepted Answer

Sucrose loading at the source, water influx, increased turgor pressure, bulk flow to sink, sucrose unloading

Question 17

Which of the following is NOT a function of phosphorus in plants?

Accepted Answer

Component of chlorophyll

Question 18

A plant is showing stunted growth and yellowing of older leaves. Which nutrient deficiency is most likely responsible?

Accepted Answer

Nitrogen

Question 19

Which of the following best describes the mutualistic relationship between mycorrhizal fungi and plant roots?

Accepted Answer

Fungi increase phosphate uptake for the plant, and the plant provides carbon to the fungi

Plant Nutrition: Photosynthesis, Nutrient Uptake, and Transport

Study Guide - Practice Questions