Class 5 Science Question Answers - Nervous System

Q1: What is the main function of our nervous system, and why is it important for our body?
Ans: The main function of our nervous system is to make us aware of our surroundings and to control all other body systems and sense organs. It helps us see, read, write, think, learn, feel, and respond. It is important because it allows our body to interact with the world and coordinate various activities.

Q2: Which organ serves as the control center of our body, and how does it send and receive messages?
Ans: The brain is the control center of our body. It sends and receives messages from different parts of the body through the spinal cord and nerves. These messages are essential for regulating our body's functions.

Q3: How is the brain protected, and what is the function of the fluid surrounding it?
Ans: The brain is protected by a bony structure called the skull. The space between the brain and the skull is filled with fluid that acts as a shock absorber, safeguarding the brain from impacts and injuries.

Q4: What is the cerebrum, and what functions does it control?
Ans: The cerebrum is the largest part of the brain. It controls our sense organs, intelligence, voice, thinking, learning, memory, and emotions.

Q5: What is the cerebellum, and what is its role in our body?
Ans: The cerebellum is the second-largest part of the brain, situated below the cerebrum. Its primary function is to control and coordinate voluntary muscle actions, such as running, walking, dancing, and maintaining balance.

Q6: What is the medulla oblongata, and what functions does it perform?
Ans: The medulla oblongata, also known as the brain stem, connects the brain to the spinal cord. It controls involuntary actions such as breathing and heart rate.

Q7: Describe the spinal cord's location and its role in the nervous system.
Ans: The spinal cord is a long bundle of nerves that extends from the medulla in the brain down to the lower end of the vertebral column. It is protected by the vertebrae and plays a vital role in the nervous system. 
The spinal cord serves two main functions:

• It carries messages between the brain and the rest of the body through nerves.
• It controls reflex actions that do not involve the brain, allowing for quick responses to stimuli.

Q8: What are nerves, and how do they transmit messages in our body?
Ans: Nerves are thread-like structures that extend from the brain and spinal cord to all body parts. They are composed of bundles of fibers (neurons) through which impulses pass between the brain or other body parts. Nerves transmit messages throughout our body.

Q9: Explain the different types of nerves and their functions.
Ans: There are three types of nerves:

• Sensory Nerves: These carry messages from sense organs to the brain or spinal cord, conveying information about temperature, smell, color, or pressure.
• Motor Nerves: These send messages from the brain or spinal cord to muscles, making muscles move.
• Mixed Nerves: These connect sensory and motor nerves, carrying messages both to and from the brain or spinal cord and various organs.

Q10: What is a reflex action, and can you provide an example of one?
Ans: A reflex action is an automatic and quick response our body makes to a stimulus, often without conscious thought. It is controlled by the spinal cord without involving the brain. For example, when we touch a sharp object, the sensory nerves in our finger send a pain message to the spinal cord, which quickly sends a command through motor nerves to move the hand away from the sharp object to avoid injury.