AQA GCSE BIOLOGY NERVOUS SYSTEM

AQA GCSE BIOLOGY NERVOUS SYSTEM Stimulus ️A change in the environment of an organism Receptor ️Specialised cell that detects stimuli Sense organ ️Specialised part of the body containing groups of receptors Neurone ️Specialised cell that carries electrical impulses. Nerve ️A bundle/group of neurons Central nervous system (CNS) ️The brain and the spinal cord. Coordinates impluses Impulse ️Electrical signal that travels along a neurone Sensory neurone ️A neuron that carries an impulse from a receptor to a part of the CNS Motor neurone ️A neurone that carries an impulse form a part of the CNS to a effector Effector organ ️A muscle or gland that responds to an impulse form a motor neurone. How do muscles respond to impulses? ️Muscles respond by contracting. How do glands respond to impulses? ️Glands respond by secreting chemicals. Relay neurone ️This connects sensory and motor neurones Synapse ️This is a very narrow gap between one neurone and the next Reflex action ️This is a rapid automatic response to a stimulus that does not involve conscious thought. Reflex arc ️The pathway for a reflex action Give examples of receptors found in the body including the stimuli they detect ️Receptors in the eyes, sensitive to light. Receptors in the ears, sensitive to sound and changes in position. Receptors in the tongue, sensitive to chemicals which enable us to taste and smell. Receptors in skin, sensitive to touch, pain, pressure and temperature change