Ability to detect + respond to stimuli is essential for survival as it allows execution of appropriate response E.g. when hand placed on hot surface, thermoreceptors detect stimulus (heat)+ initiate withdrawal of hand to prevent injury Environments contain different kinds of stimuli hence, many – organisms have a range of different, specialised receptor types Type of receptor Stimulus Organ Mechanoreceptor Mechanical stimuli, i.e. Sound Hair cells (ear) Gravity Skin Touch Pressure Thermoreceptors Temperature, i.e. - Skin Hot Cold Electromagnetic receptors Electromagnetic i.e. - Visible light - Eye (photoreceptors) - Ultraviolet - Infra-red - Pit organs (snakes) Chemoreceptors Chemicals Nose Tongue
Ability to detect + respond to stimuli is essential for survival as it allows execution of appropriate response E.g. when hand placed on hot surface, thermoreceptors detect stimulus (heat)+ initiate withdrawal of hand to prevent injury Environments contain different kinds of stimuli – hence, many organisms have a range of different, specialised receptor types Type of receptor Stimulus Organ Mechanoreceptor Mechanical stimuli, i.e. Sound Gravity Touch Pressure Hair cells (ear) Skin Thermoreceptors Temperature, i.e. Hot Cold - Skin Electromagnetic receptors Electromagnetic i.e. - Visible light - Eye (photoreceptors) - Ultraviolet - Infra-red - Pit organs (snakes) Chemoreceptors Chemicals Nose Tongue
communication_student_notes.docx