Communication, Homeostasis, and Energy: The Nervous and Hormonal System

These flashcards cover key concepts related to the nervous and hormonal systems as discussed in the lecture.

What are receptors in the nervous system responsible for?

Receptors detect changes in the environment known as stimuli.

What signals to the CNS when receptors detect stimuli?

They initiate an electrical impulse through a sensory neuron.

What is the role of the coordination centre in the nervous system?

It processes information received from various receptors and coordinates a response.

What types of receptors are sensitive to light?

Photoreceptors.

What triggers an action potential in a sensory neuron?

A change in potential difference across the membrane that exceeds the threshold level.

What structure do Pacinian corpuscles belong to?

Mechanoreceptors, which respond to changes in pressure.

What is a neuron?

A cell that carries information to and from the central nervous system in the form of electrical impulses.

What is resting potential in a neuron?

The charge difference across the membrane when the neuron is not firing, typically around -70 mV.

What causes depolarisation during an action potential?

Opening of sodium ion channels in the membrane.

What is saltatory conduction?

A type of nervous transmission that occurs in myelinated neurones, where action potentials jump from node to node.

What is the process by which neurotransmitters cross the synaptic cleft?

Neurotransmitters are released from the presynaptic neurone and diffuse across the synaptic cleft to bind to receptors on the postsynaptic neurone.

What is synaptic divergence?

When one neurone forms connections to multiple neurones, sending action potentials to different parts of the body.

How do hormones exert their effects on target cells?

Hormones bind to specific receptors on target cells, triggering a response inside the cell.

What is the difference in response speed between the nervous system and the endocrine system?

The endocrine system is slower to bring about an effect compared to the nervous system.

What do adrenal glands secrete during times of stress?

Catecholamines including adrenaline and noradrenaline.

What effect does cortisol have on the body?

It suppresses the immune system and increases blood pressure.

What is the role of insulin in the body?

Insulin lowers blood glucose levels.