Concept explainers
The water necessary for photosynthesis
- is split into H2 and O2.
- is directly involved in the synthesis of carbohydrates.
- provides the elections to replace lost electrons in photosystem II.
- provides H+ needed to synthesize G3P.
- does none of the above.
Introduction:
The Calvin cycle utilizes the energy produced by the light-dependent reaction into synthesizing carbohydrates from carbon dioxide. The NADPH (nicotinamide adenine dinucleotide phosphate) acts as a reducing agent that adds the high energy electrons to the carbon dioxide molecule to form polysaccharide (glucose).
Answer to Problem 1TY
The correct answer is option (c) provides the electrons to replace lost electrons in photosystem II.
Explanation of Solution
Explanation/justification for the correct answer:
Option (c) provides the electrons to replace lost electrons in photosystem. Water does provide lost electrons for photosystem II that are used for the electron transport chain. So, the correct answer is option (c).
Explanation for incorrect answer:
Option (a) is split into H2 and O2. Splitting of water under the presence of light to yield hydrogen and oxygen is known as photolysis of water to provide electrons for the reaction. So, this is an incorrect option.
Option (b) is directly involved in the synthesis of carbohydrates. Water is no directly involved in the synthesis of carbohydrates as it provides electrons for reduction of NADH that participates in the production of carbohydrates. So, this is an incorrect option.
Option (d) provides H+ needed to synthesize G3P. The protons for the synthesis for G3P come from the photolysis of water, but that is not the necessary source of protons they can also come from thylakoid membrane. So, this is an incorrect answer.
Option (e) does none of the above. The water is necessary for the compensation of the electrons that are lost in the photosystem II and these electrons participate in the electron transport chain. So, this is an incorrect answer.
Water is required as a source of electrons in the light reaction where photosystems get activated and lead to an electron transport chain to produce energy-rich molecules. Hence, the correct answer is option (c) provides the electrons to replace lost electrons in photosystem II.
Want to see more full solutions like this?
Chapter 7 Solutions
Principles of Biology
- Which of the following substances does not participate in the Calvin-Benson cycle? a. ATP c. NADPH e. PGAL b. O2 d. RuBP f. CO2arrow_forwardDraw a diagram of the dark phase of photosynthesis. You must represent this phase in the form of a cycle indicating the parts of carboxylation, reduction, generation of hexoses and regeneration. Ribulose, CO2, rubisco, phosphoglycerate (PGA), bisphosphoglycerate, phosphoglyceraldehyde (PGAL), ATP, ADP, NADPH, NADP, kinase, fructose, and glucose should appear.arrow_forwardWhich of the following reactions produces the oxygen released by photosynthesis? chemiosmosis reduction of NADP+ splitting of water molecules electron transfer in photosystem Iarrow_forward
- Which of the following is produced during the light reactions of photosynthesis? C6H12O6 CO2 O2 ADParrow_forwardWhy do the cells of photosynthetic organisms contain accessory pigments? Accessory pigments provide a backup source of energy if the main pigment type fails. Accessory pigments direct light toward the primary pigment. Accessory pigments optimize the amount of energy that can be harvested in specific environments. Accessory pigments provide structural support for the primary pigments. Accessory pigments allow photosynthesis to occur at any time of the day.arrow_forwardPhotosynthesis and Respiration are opposing processes. One is required to produce food, the other to derive energy from food. Each of these processes involves a cycle to complete its goal. For Photosynthesis it is the Calvin Cycle; for Respiration it is the Krebs Cycle. Listed below are features of both cycles. Indicate which 5 of them are associated with the Calvin Cycle. Creates glucose ATP and CO2 are used ATP and CO2 are produced O A catabolic process An anabolic process. Oxidizes glucose O Occurs in mitochondria O Occurs in chloroplasts Occurs only in green organisms Occurs in all organismsarrow_forward
- Identify the correct compound to create a chemical equation that represents Photosynthesis. + Drag and drop the right reactants and products of the Light Dependent and Light Independent (aka Dark) Reactions. Chloroplast NADPH NADP+ ADP Water - H20 Calvin Cycle Glucose - C6H1206 ATP Light Reaction Thylakoids Stroma O2 Carbon Dioxide CO2 Identify the reactants and products that are used and given off by plants and animals.arrow_forwardDuring photosynthesis, low energy electrons are struck by light, bumped up to higher energy levels, and then incorporated into organic molecules. Where does the chloroplast or Cyanobacterium obtain these electrons? From carbon dioxide From sunlight From water From ATParrow_forwardWhich of the following steps is responsible for oxygen gas production in photosynthesis? Excitation of a photosystem II electron Excitation of a photosystem I electron Breakdown of water to replace a photosystem II electron Breakdown of water to replace a photosystem I electron More than one answer is correctarrow_forward
- Which of the following statements is/are TRUE for photosynthesis? The e- moves from H20 to NADP+. Some of the products from the dark reaction are required in the light reaction. It is an exergonic process that naturally by using energy from light It Involves conversion of 02 to H20 and C02 to glucose.arrow_forwardThe process of photosynthesis can be modeled in various ways. For example, a chemical equation is one way to represent photosynthesis. 6CO, + 6H,0 ++ +→ 60, + C,H,,O,arrow_forwardWhich of the following is FALSE about photosynthesis? Group of answer choices: -Organisms that can utilize light energy as a food source are called autotrophs. -Photosynthesis occurs in the chloroplasts. -The light phase of photosynthesis produces ATP and NADH. -Carbohydrates, with the aid of energy and reducing power produced from the light phase, are synthesized from carbon dioxide and water.arrow_forward
- Biology 2eBiologyISBN:9781947172517Author:Matthew Douglas, Jung Choi, Mary Ann ClarkPublisher:OpenStax