Ncert diagram based questions part-5

Diagrams are an essential part of the NCERT textbooks, especially in science subjects. Students need to understand these diagrams to get a better grasp of the concepts. Here are some common diagram-based questions and their explanations.

1. Explain the structure of a plant cell.

The structure of a plant cell is as follows:

• Cell wall - It is a non-living, rigid outer layer that provides support and protection to the cell.

• Cell membrane - It is a thin, flexible layer that surrounds the cell and controls the movement of substances in and out of the cell.

• Nucleus - It is the control center of the cell that contains genetic material and regulates the cell's activities.

• Cytoplasm - It is the gel-like substance inside the cell where most of the cellular processes occur.

• Mitochondria - They are the powerhouses of the cell that produce energy through cellular respiration.

• Chloroplasts - They are present only in plant cells and are the sites of photosynthesis.

• Vacuoles - They are storage structures that store water, nutrients, and waste products.

2. Explain the process of photosynthesis.

The process of photosynthesis involves the following steps:

• Absorption of light - Chlorophyll pigments present in chloroplasts absorb light energy from the sun.

• Conversion of light energy - The absorbed light energy is converted into chemical energy in the form of ATP and NADPH.

• Splitting of water - Water molecules are split into hydrogen and oxygen using the energy from ATP.

• Formation of glucose - Carbon dioxide from the air is combined with the hydrogen ions to form glucose.

• Release of oxygen - The oxygen produced during the splitting of water is released into the atmosphere.

3. Explain the structure of a neuron.

The structure of a neuron is as follows:

• Cell body - It is the main part of the neuron that contains the nucleus and other organelles.

• Dendrites - They are branch-like structures that receive signals from other neurons and transmit them to the cell body.

• Axon - It is a long, slender projection that transmits signals away from the cell body.

• Myelin sheath - It is a fatty insulating layer that covers the axon and speeds up the transmission of signals.

• Nodes of Ranvier - They are gaps in the myelin sheath that allow the signal to jump from one node to the next, increasing the speed of transmission.

• Terminal branches - They are small branches at the end of the axon that transmit signals to other neurons or muscle cells.

In conclusion, understanding diagrams is crucial for students to excel in science subjects. By breaking down diagrams into their component parts, students can get a better understanding of the concepts and improve their performance in exams.