Ch 10Neural Control and Coordination — Class 11 Zoology, concept-first.

Our body performs an enormous range of everyday functions without us consciously directing them: the eyes see, the ears hear, the heart beats on its own steady rhythm, air moves in and out of the lung…

Every living cell in the body needs to know what is happening around it and respond in a coordinated way, and that job belongs to the neural system.

In humans, the neural system is organised into two connected divisions: the central neural system (CNS), made up of the brain and spinal cord, and the peripheral neural system (PNS), made up of all th…

A neuron is a microscopic cell built of three main parts: the cell body (soma), the dendrites, and the axon.

Before an impulse can travel, the axon has to be electrically 'primed' by an uneven distribution of ions across its membrane.

The transmission of a nerve impulse unfolds in two connected phases: the resting membrane potential, which is the baseline state of a neuron that is not currently signalling, and the action membrane p…

The point where one neuron hands its signal to the next is called a synapse. The neuron delivering the signal is the presynaptic neuron, and the one receiving it is the postsynaptic neuron; between th…

The central neural system (CNS) is made up of the brain and the spinal cord, and both structures get real physical protection: they sit inside bone (the skull for the brain, the vertebral column for t…

The brain is the body's command and control centre and its main site of information processing, sitting in the cranial cavity and wrapped in three protective layers — the tough outer duramater, a thin…

The spinal cord is a long, slender, cylindrical extension of nervous tissue that continues on from the brain stem, running down inside the bony vertebral canal and, like the brain, wrapped by the same…

A reflex action is the body's way of handling situations where a response has to be immediate — faster than waiting for the brain to consciously decide would allow.

The peripheral neural system (PNS) covers every bit of nervous tissue that lies outside the CNS — this includes nerves (cord-like bundles enclosing many neurons), ganglia (small clusters of neuron cel…

The peripheral neural system's outgoing (motor) pathways split into two systems with very different jobs.

Our senses are how the body notices change, both in the world around it and within itself. Two related but distinct processes are involved: sensation, simply becoming aware that a stimulus has occurre…

The eye is the organ of vision, sitting in the bony orbit of the skull and held there by six extrinsic muscles — the superior, inferior, lateral and medial rectus muscles plus the superior and inferio…

The ear does double duty as the organ of both hearing and equilibrium, and is divided anatomically into three regions: the external ear, the middle ear and the internal (inner) ear.

Balance is a sense in its own right, part of what is called proprioception — the ability to sense the body's own position, movement and orientation.

Smell and taste are both carried by chemoreceptors — receptors that respond to dissolved or airborne chemical molecules rather than to physical stimuli like light, sound or pressure.

Taste is often described as the most pleasurable of the senses, and it is detected by structures called taste buds, most of which sit on the tongue's papillae — small projections that also give the to…

Skin is not only the body's largest organ but also its organ of touch, carrying millions of microscopic sensory receptors spread across its surface.

This Evaluation set draws on every part of the chapter — the structure and firing of a neuron, the organisation of the CNS and PNS, reflex action, and each of the five sense organs — through a mix of…

Sample papers and previous-year board questions for this subject.