Correct Option: B. Dendrite Explanation of the Correct Answer Neurons are specialized cells in the nervous system that transmit information through electrical and chemical signals. Each neuron has several key components, including the dendrites, soma (cell body), axon, and myelin sheath. Among these, the dendrites play a crucial role in receiving signals from other neurons.

1. Function of Dendrites:
2. Dendrites are tree-like structures that extend from the soma of the neuron. Their primary function is to receive incoming signals from other neurons. They contain numerous receptors that bind to neurotransmitters (chemical messengers) released by neighboring neurons. When these neurotransmitters bind to the receptors on the dendrites, they can generate small electrical changes in the neuron, known as postsynaptic potentials.
3. Signal Integration:
4. The signals received by the dendrites are integrated in the soma. If the cumulative effect of these signals is strong enough to reach a certain threshold, an action potential (a rapid electrical signal) is generated and travels down the axon to communicate with other neurons or muscles.
5. Structure and Surface Area:
6. Dendrites have a large surface area due to their branching structure, which allows them to receive signals from many other neurons simultaneously. This is essential for the complex communication that occurs in the nervous system.

Why the Other Options are Incorrect A. Axon: - The axon is responsible for transmitting electrical impulses away from the soma to other neurons or target tissues. It does not receive signals; rather, it conducts action potentials that have been generated in the soma. Therefore, the axon is not involved in the initial reception of signals. C. Soma: - The soma, or cell body, contains the nucleus and organelles of the neuron. While it plays a role in processing the signals received from the dendrites, it is not primarily responsible for receiving signals. Its main function is to maintain the cell's health and integrate incoming signals. D. Myelin Sheath: - The myelin sheath is a fatty layer that surrounds the axon of some neurons, providing insulation and increasing the speed of electrical signal transmission. It does not play a role in receiving signals; instead, it facilitates the efficient conduction of action potentials along the axon. Summary of Key Points

• Dendrites are the primary structures responsible for receiving signals from other neurons.
• They contain receptors for neurotransmitters and have a large surface area for signal reception.
• The soma integrates these signals, while the axon transmits them away from the neuron.
• The myelin sheath insulates the axon and speeds up signal transmission but does not receive signals.

Revision Summary

• Dendrites receive signals from other neurons through neurotransmitter binding.
• The soma processes and integrates these signals.
• The axon transmits action potentials away from the neuron.
• The myelin sheath insulates the axon, enhancing signal speed but does not participate in signal reception.