Selina Class 7 Biology Solutions Chapter-6 Nervous System
The study of the human body becomes more interesting with Selina Class 7 Biology Solutions Chapter-6 Nervous System. This chapter explains how the brain, spinal cord, and nerves work together to control different activities of the body. Students preparing through Selina Solutions for ICSE board can easily understand the structure and functions of the nervous system with simple explanations and textbook-based answers. The chapter is important because it introduces students to coordination in the human body, reflex actions, sense organs, and the role of nerves in carrying messages between body parts and the brain.
Find the Exercise-wise PDF of Selina Class 7 Biology Solutions chapter-6 Nervous System.
Overview of the Nervous System
The nervous system is one of the most important systems in the human body. It controls body movements, thinking, memory, emotions, and reactions to changes in the surroundings. The chapter explains that the nervous system helps different organs work in coordination.
The nervous system mainly consists of:
- Brain
- Spinal cord
- Nerves
These organs work together to receive information, process it, and produce suitable responses.
Structure and Functions of the Brain
The brain is the control center of the body. It receives messages from sense organs and sends instructions to muscles and organs. Chapter-6 explains the three major parts of the brain:
Cerebrum
The cerebrum is the largest part of the brain. It controls thinking, memory, intelligence, learning, and voluntary actions such as writing and walking.
Cerebellum
The cerebellum helps maintain body balance and coordinates muscle movements. It allows us to perform activities smoothly without losing balance.
Medulla Oblongata
This part controls involuntary actions like breathing, heartbeat, and digestion. These functions continue automatically even when we are asleep.
Students are often asked to identify these parts and explain their functions in school examinations.
Role of the Spinal Cord
The spinal cord is a long bundle of nerves protected by the vertebral column. It connects the brain to different parts of the body. Messages from body organs travel to the brain through the spinal cord.
The chapter also explains reflex actions, which are quick automatic responses to danger. For example, pulling the hand away from a hot object happens through reflex action controlled mainly by the spinal cord.
Importance of Nerves
Nerves are thin thread-like structures spread throughout the body. They carry messages between the brain, spinal cord, and body organs. The chapter explains two types of nerves:
- Sensory nerves carry messages from sense organs to the brain.
- Motor nerves carry instructions from the brain to muscles and glands.
Understanding these functions helps students learn how the body reacts quickly to different situations.
Sense Organs and Their Connection with the Nervous System
Sense organs play an important role in receiving information from the surroundings. The eyes, ears, nose, tongue, and skin are connected to the nervous system through nerves.
The chapter explains how:
- Eyes help in vision
- Ears help in hearing and balance
- Nose detects smell
- Tongue identifies taste
- Skin senses touch, heat, and pain
These concepts are important for understanding coordination between organs and the nervous system.
Why This Chapter is Important for ICSE Students
Chapter-6 Nervous System is important because it introduces students to body coordination and control mechanisms. Many concepts from this chapter are useful in higher biology classes. Students also learn scientific terms and functions that frequently appear in exams.
The exercise questions help students improve diagram labeling, definitions, and explanation-based answers. Regular revision of this chapter helps students understand the functioning of the human body in a systematic way.