OCR General Certificate of Secondary Education (GCSE) Biology Practice Exam

What are dendrites primarily involved in?

1. Connecting with muscles

2. Transmitting nerve signals quickly

3. Connecting with other neurons

4. Insulating axons

The correct answer is: Connecting with other neurons

Dendrites are primarily involved in connecting with other neurons. These structures extend from the neuron’s cell body and serve as the primary sites for receiving signals from other neurons. They play a crucial role in the transmission of information within the nervous system by collecting neurotransmitters released by neighboring neurons. This connection allows dendrites to gather and integrate multiple signals, which then contribute to the neuron's overall response or action potential. In contrast, the other options describe different roles that are not associated with dendrites. For instance, connections with muscles are facilitated by motor neurons through axon terminals rather than dendrites. The rapid transmission of nerve signals is primarily the function of the axon, as it is the long, slender part of the neuron designed for fast signal conduction. Insulation of axons is performed by myelin sheaths, which speed up signal transmission, but this is unrelated to the function of dendrites. Therefore, the role of dendrites in connecting with other neurons is fundamental to the communication processes in the nervous system.