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Brain Cell

Transcript: Hey Brainiacs! Have you ever stopped to wonder how you can instantly feel a cold breeze, remember your best friend’s name,move our hands or just... think? All this happens because of one special cell in our body – the Neuron! These incredible cells are the fundamental building blocks—the electrical wiring—that let your body communicate with lightning speed. They are the reason you can react, learn, and experience the world. A typical neuron has: dendrites : Short, branch-like structures. Receive signals from other neurons or sensory receptors. “Input area” of the neuron. cell body , soma : Contains nucleus and organelles. Controls metabolism and protein synthesis. Integrates (collects and processes) information. Axon Hillock (Trigger Zone): Cone-shaped region between soma and axon. Decision-making point — if the signal is strong enough, an action potential is generated here. Acts as the "gateway" for nerve impulses. axon: Long, thin fiber. Carries signals away from the cell body. Can be myelinated (covered with myelin sheath) for faster signal conduction. Gaps in myelin = Nodes of Ranvier → help signals jump (saltatory conduction). axon terminal or synaptic knob: Release neurotransmitters Communicate with next neuron, muscle, or gland. Types of Neurons (Based on Structure): 1. Unipolar Only one process. Rare in humans (mainly in embryos). 🔹 2. Pseudounipolar One process that divides into two branches. Found in dorsal root ganglia. Mainly sensory neurons. 🔹 3. Bipolar One dendrite + one axon. Found in retina, inner ear, olfactory epithelium. Involved in special senses. 🔹 4. Multipolar (most common) Many dendrites + one axon. Found in brain and spinal cord. Examples: Motor neurons, interneurons Types of Neurons (Based on Function): ✅ A. Sensory (Afferent) Neurons Carry signals from receptors to CNS. Example: Touch, pain, temperature. ✅ B. Interneurons (Association neurons) Located inside CNS. Connect sensory and motor neurons. Responsible for processing, thinking, memory. Most abundant type. ✅ C. Motor (Efferent) Neurons Carry signals from CNS to muscles or glands. Cause movement or secretion. Example: Moving your hand, contracting heart, blinking eyes. Quick Recap (30 sec) ✔ Neuron = functional unit of nervous system ✔ Structure = dendrites, cell body, axon ✔ Structural types = unipolar, pseudounipolar, bipolar, multipolar ✔ Functional types = sensory, interneuron, motor