Question 1

What is the role of the nervous system in humans according to the Edexcel GCSE Biology curriculum?

Accepted Answer

In the Edexcel GCSE Biology curriculum, the nervous system is described as a complex network responsible for coordinating the body's response to internal and external stimuli. It consists of the central nervous system (CNS) and the peripheral nervous system (PNS), which work together to process information and control bodily functions.

Question 2

How do neurons transmit signals in the human nervous system?

Accepted Answer

Neurons transmit signals through electrical impulses known as action potentials. These impulses travel along the axon of a neuron and are transmitted to the next neuron via synapses. At the synapse, neurotransmitters are released, which cross the synaptic gap and bind to receptors on the next neuron, continuing the signal transmission.

Question 3

What is the difference between sensory and motor neurons in the context of nervous control?

Accepted Answer

Sensory neurons are responsible for carrying signals from sensory receptors to the central nervous system, allowing the body to perceive stimuli. Motor neurons, on the other hand, transmit signals from the central nervous system to effectors such as muscles and glands, enabling a response or action.

Question 4

How does the reflex arc function as part of the nervous system?

Accepted Answer

The reflex arc is a neural pathway that controls reflex actions. It involves sensory neurons that detect a stimulus and send signals to the spinal cord, where interneurons process the information and immediately relay signals to motor neurons. This results in a quick, involuntary response, bypassing the brain for faster reaction times.

Question 5

Why is the myelin sheath important for nerve impulse transmission?

Accepted Answer

The myelin sheath is a fatty layer that surrounds the axons of many neurons. It acts as an insulator, increasing the speed of nerve impulse transmission by allowing the impulse to jump between gaps in the sheath called nodes of Ranvier. This process, known as saltatory conduction, ensures efficient and rapid communication within the nervous system.

Nervous Control in Humans

Short Notes - Nervous Control in Humans

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Nervous Control in Humans — frequently asked questions