Question

Von Sachs studies shows that (a) Green substance in plants is located in special bodies within the plant cell. (b) Glucose is made in green part of plant. (c) Glucose is usually stored as starch. (d) All the above

Short answer

The correct answer is (d) All the above; since each of the statements (a), (b), and (c) is accurate and correct in the context of plant cells and photosynthesis.

Step-by-step solution

Understand Each Choice

The first step is to understand the meaning and implications of each possible choice. (a) Green substances are usually chlorophyll, located in chloroplasts within the plant cell. These are responsible for photosynthesis. (b) This statement suggests that glucose, a simple sugar, is produced in these green parts of the plant during photosynthesis. (c) Glucose, after it's made, can be stored in plants as starch. This is a common storage form of energy for plants.

Analyze the Choices

If we analyze each choice, we find that each of them is scientifically accurate. Chlorophyll (a green substance) is located in the plant's chloroplasts and responsible for photosynthesis, glucose is indeed formed in the green parts of the plant, and it is often stored as starch in plants.

Select the Correct Answer

Since each of the choices (a), (b), and (c) is correct, the correct answer to this multiple-choice question must be (d), which states that all the above answers are correct.

Key concepts

Chlorophyll

Chlorophyll is the green pigment found in plants that is crucial for the process of photosynthesis. This pigment is what gives plants their characteristic green color. It plays a vital role in absorbing sunlight.

Once the sunlight is absorbed, chlorophyll helps convert this light energy into chemical energy. This conversion process is paramount as it initiates the sequence of reactions that lead to the production of glucose.

Without chlorophyll, plants would not be able to harness the energy from sunlight needed for growth and survival, as it's the key component in capturing that energy from the light spectrum.

Chloroplasts

Chloroplasts are the specialized organelles within plant cells that house chlorophyll. They are the sites where photosynthesis takes place.

These tiny structures are packed with thylakoids, which are sac-like membranes. These membranes are arranged in stacks called grana, where the light-dependent reactions of photosynthesis occur.

The chloroplasts also contain a fluid known as stroma, where the light-independent reactions, also known as the Calvin cycle, take place. This is where the chemical transformation occurs, resulting in the creation of glucose from carbon dioxide and water.

Glucose Production

Glucose production is a critical outcome of photosynthesis. It begins in the chloroplasts where light energy has been captured.

The energy from light allows water molecules to be split, releasing oxygen and hydrogen. This process, along with the absorption of carbon dioxide, facilitates the formation of glucose, a simple sugar.

Glucose is immensely important because it serves as the primary source of energy for plant cells. It fuels various metabolic processes and aids in the growth and repair of plant tissues.

Moreover, this glucose can be transported to different parts of the plant, serving as a building block for more complex carbohydrates.

Starch Storage

Starch storage is essential for plants as it allows them to store energy for future use. Once glucose is produced in the plant cells, it can be converted into starch.

This conversion is crucial because starch is insoluble and does not readily dissolve in water, making it an efficient form of stored energy. This characteristic allows plants to maintain stable energy reserves.

When energy demands are high, such as during nighttime or periods of low sunlight, plants can break down starch back into glucose. This enables them to continue cellular activities and maintain growth, regardless of immediate photosynthetic activity.