a. Describe the composition and function of the cell body.
b. How are axons and dendrites alike? In what ways (structurally and functionally) do they differ?

Verified step by step guidance

1. For part (a), start by defining the cell body (also called the soma) of a neuron. Explain that it contains the nucleus and most of the organelles, such as mitochondria, ribosomes, and endoplasmic reticulum, which are essential for the neuron's metabolic activities and protein synthesis.
2. Next, describe the function of the cell body, emphasizing that it integrates incoming signals from the dendrites and generates outgoing signals to the axon. It also maintains the neuron's health and supports its overall function.
3. For part (b), begin by identifying the similarities between axons and dendrites: both are extensions of the neuron that conduct electrical signals and are covered by the plasma membrane with cytoplasm inside.
4. Then, explain the structural differences: dendrites are typically short, branched, and numerous, while axons are usually long, singular, and may have branches called axon collaterals. Also, dendrites have a rough surface due to synaptic inputs, whereas axons have a smooth surface.
5. Finally, discuss the functional differences: dendrites receive incoming signals from other neurons and transmit them toward the cell body, whereas axons carry outgoing signals away from the cell body to other neurons, muscles, or glands.

Key Concepts

Cell Body (Soma) Composition and Function

The cell body, or soma, contains the nucleus and cytoplasm with organelles like mitochondria and ribosomes. It integrates incoming signals and maintains cell health by producing proteins and energy necessary for neuron function.

Structure and Function of Axons

Axons are long, slender projections that transmit electrical impulses away from the cell body to other neurons or muscles. They often have myelin sheaths to speed signal conduction and end in terminal branches for communication.

Structure and Function of Dendrites

Dendrites are branched extensions from the cell body that receive incoming signals from other neurons. They have numerous receptors and increase the surface area for synaptic input, playing a key role in signal integration.