Question

Which of the following cells do not divide once it is differentiated? (a) Interstitial cells (b) Nerve cells (c) Myeloid cells (d) Glial cells

Short answer

The correct answer is (b) Nerve cells.

Step-by-step solution

Understand the terms

Understand what each type of cell is and what function it serves in the organism. Interstitial cells: These cells are found in the testes, and they produce testosterone. They have the potential to divide. Nerve cells (Neurons): These are specialized cells designed to transmit information throughout the body, and cannot divide once fully differentiated. Myeloid cells: These cells are types of white blood cells, including monocytes, neutrophils, eosinophils, and basophils. They can divide. Glial cells: These cells, found in the nervous system, are responsible for providing structural support, nutrition, and other functions to neurons. They can divide.

Identify the non-dividing cell

From the above descriptions, it is clear that nerve cells or neurons do not divide once they are fully differentiated.

Key concepts

Cell Differentiation

Cell differentiation is the process by which cells become specialized to perform specific functions within an organism. This process begins during embryonic development and continues throughout an organism's life, allowing it to grow, develop, and repair. As cells differentiate, they undergo changes in size, shape, polarity, metabolic activity, and responsiveness to signals.

During differentiation, a cell expresses specific proteins that enable it to perform its specialized function. This is why a muscle cell looks and acts very differently from a nerve cell. For example, nerve cells (also known as neurons) differentiate to have long projections called axons and dendrites that allow them to send and receive electrical signals.

Understanding cell differentiation helps scientists and doctors comprehend how the human body develops and functions, and it also helps in researching disease treatment, particularly in regenerative medicine and cancer treatment, where differentiation plays a crucial role.

Non-Dividing Cells

Non-dividing cells are cells that do not undergo further division once they have fully differentiated. An example of non-dividing cells includes nerve cells or neurons. When neurons mature, they exit the cell cycle, entering a phase known as quiescence, where they no longer replicate.

This inability to divide makes neurons unique compared to other cells that continuously regenerate. Neurons maintain their function throughout an individual's life without needing replacement. This property of neurons is why nerve damage tends to be more permanent compared to other tissues, making neurodegenerative diseases particularly challenging to treat.

Because non-dividing cells are so specialized, their loss or damage can have serious implications on the overall function of the body. Research in regenerative medicine aims to find ways to regenerate or replace these cells to treat various conditions.

Neurons and Neurobiology

Neurons, often referred to as nerve cells, are the building blocks of the nervous system. They are responsible for transmitting information throughout the body via electrical signals. A neuron typically consists of three parts: the cell body, dendrites, and an axon.

1. **Cell Body (Soma):** Contains the nucleus and essential organelles, processing incoming signals.
2. **Dendrites:** Tree-like structures that receive messages from other neurons and convey them to the cell body.
3. **Axon:** A long, slender projection that transmits electrical impulses away from the cell body to other neurons or muscle cells.

Neurons communicate through synapses, where neurotransmitters are released, allowing the propagation of signals. These signals enable everything from muscle contraction to processing complex thoughts and emotions.

Neurobiology, the study of neurons and the nervous system, is crucial for understanding how our bodies function. It covers various topics, from how neurons develop and form networks to how they communicate and affect behavior. This knowledge is key for developing treatments for neurological disorders and brain injuries.