Chapter 18 of Class 11 Biology is called Neural Control and Coordination. This chapter helps us understand how our body receives signals, processes them, and responds to the surroundings. It focuses on the nervous system, which includes the brain, spinal cord, neurons, reflex actions, and sensory perception. It explains how coordination between various parts of the body happens through neural and chemical means.
I chose to write about this chapter because it is a key part of human physiology and also one of the most asked topics in competitive exams like NEET. Many students get confused with concepts like synaptic transmission, reflex arc, and different parts of the brain. So I thought of simplifying it here. Understanding how our body reacts to pain, how we balance while walking, or how thoughts form in our brain makes this chapter not only informative but also very relatable. Once you get the basic terms and structure right, this chapter becomes one of the most fascinating parts of biology.
Overview of Neural Control and Coordination
Our body needs a system to control and coordinate all activities. This is done by the nervous system and the endocrine system. This chapter mainly focuses on the nervous system and its functioning.
Types of Coordination
- Neural Coordination: Done by the nervous system through electrical impulses
- Chemical Coordination: Done by hormones (will be discussed in the next chapter)
The Nervous System
The human nervous system has two main parts:
- Central Nervous System (CNS) – brain and spinal cord
- Peripheral Nervous System (PNS) – cranial and spinal nerves
Neurons
Neurons are the functional units of the nervous system. A neuron has three parts:
- Cell body (soma)
- Dendrites – receive impulses
- Axon – sends signals away
Neurons communicate through synapses, and this transmission can be electrical or chemical.
Types of Neurons
| Type | Function |
|---|---|
| Sensory neurons | Carry messages from receptors to CNS |
| Motor neurons | Carry commands from CNS to effectors |
| Interneurons | Connect sensory and motor neurons in CNS |
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Click here to download the official NCERT PDF of Chapter 18 – Neural Control and Coordination
Download NCERT Class 11 Biology Chapter 18 PDF
