Which step in photosynthesis does not need light?(1 point)
Responses
Oxygen is released.
Oxygen is released.
Carbon dioxide and hydrogen combine to make glucose.
Carbon dioxide and hydrogen combine to make glucose.
Water splits into hydrogen and oxygen.
Water splits into hydrogen and oxygen.
Chlorophyll absorbs energy.
Carbon dioxide and hydrogen combine to make glucose.
A scientist performs an experiment by placing petroleum jelly on under side of plant leaves. This blocks the leaves’ stomata. The plant continues to be watered and is located in a sunny spot. What will the scientist observe?(1 point)
Responses
The plant goes into hibernation.
The plant goes into hibernation.
The plant grows and thrives.
The plant grows and thrives.
The plant grows, flowers, and seeds.
The plant grows, flowers, and seeds.
The plant withers and dies.
The plant withers and dies.
How many carbon atoms combine in the photosynthesis reaction?(1 point)
Responses
1
1
6
6
2
2
12
6
The step in photosynthesis that does not require light is when water splits into hydrogen and oxygen. This process is called photolysis and occurs in the thylakoid membrane of the chloroplasts in plant cells. Here's how you can determine the correct answer:
1. Review the steps of photosynthesis: Photosynthesis is the process by which plants convert light energy into chemical energy in the form of glucose. It consists of two main stages: the light-dependent reactions and the light-independent reactions (also known as the Calvin cycle).
2. Identify the step that does not involve light: In the light-dependent reactions, light energy is absorbed by chlorophyll, which energizes electrons that are used to split water molecules. This splitting of water releases oxygen as a byproduct. However, this step requires light as the source of energy. So, it is not the correct answer.
3. Consider the remaining options: In the light-independent reactions (Calvin cycle), carbon dioxide and hydrogen combine to produce glucose through a series of enzyme-mediated reactions. This step does not rely on light directly, as it utilizes the products (ATP and NADPH) generated during the light-dependent reactions. This is also not the correct answer.
4. Determine the correct answer: This leaves us with the step where water splits into hydrogen and oxygen. This process, known as photolysis, takes place during the light-dependent reactions and does not require light. Consequently, this is the correct answer to the question.
Therefore, the correct response is: Water splits into hydrogen and oxygen.