1. Sensory Reception Sensory Receptors Sensory Receptors Photoreception Mechanoreception

2. Sensory Receptors Sensory reception is the conversion of environmental stimuli to nerve impulsesSensory reception is the conversion of environmental stimuli to nerve impulsesSensory reception Sensory reception Sensory reception is performed by sensory receptorsSensory reception is performed by sensory receptors sensory receptors sensory receptors Sensory receptors are nerve endings and cells that detect sensory stimuliSensory receptors are nerve endings and cells that detect sensory stimuli Sensation is the arrival of sensory impulses at the cerebral cortexSensation is the arrival of sensory impulses at the cerebral cortex

3. Sensory Reception There are several types of sensory receptorsThere are several types of sensory receptorssensory receptorssensory receptors Sensory adaptation occurs when a receptor becomes accustomed to a stimulusSensory adaptation occurs when a receptor becomes accustomed to a stimulus Interpretation of stimuli is coordinated by the central nervous systemInterpretation of stimuli is coordinated by the central nervous system The sensitivity to stimuli is determined by the receptor and the portion of the brain devoted to interpreting the impulsesThe sensitivity to stimuli is determined by the receptor and the portion of the brain devoted to interpreting the impulsesbrain

4. Photoreception The eye is a sensory organ that interprets light stimuliThe eye is a sensory organ that interprets light stimulieye The parts of the eye help to collect light, focus light and convert light energy into nerve impulsesThe parts of the eye help to collect light, focus light and convert light energy into nerve impulsesparts of the eyeparts of the eye The ability of the eye to focus on near and then distant objects is called accommodationThe ability of the eye to focus on near and then distant objects is called accommodationfocus accommodationfocus accommodation

5. Photoreception The sensory reception takes place on the rods and conesThe sensory reception takes place on the rods and conesrods and conesrods and cones Rods send impulses when rhodopsin is converted to opsin and retinene using light energyRods send impulses when rhodopsin is converted to opsin and retinene using light energy Cones are sensitive to red, green or blue light and send impulses alone or together to sense infinite coloursCones are sensitive to red, green or blue light and send impulses alone or together to sense infinite coloursCones

6. Photoreception Interpretation of vision is coordinated by the occipital lobe of the cerebral cortexInterpretation of vision is coordinated by the occipital lobe of the cerebral cortexInterpretation The blind spot is the portion of the retina that contains no rods or conesThe blind spot is the portion of the retina that contains no rods or cones

7. The Eye Disorders of the eye include:Disorders of the eye include: 1.Nearsightedness (myopia) myopia 2.Farsightedness (hyperopia) hyperopia 3.Astigmatism Astigmatism 4.Cataracts Cataracts 5.Colour blindness Colour blindnessColour blindness 6.Glaucoma Glaucoma

8. Mechanoreception and Chemoreception Mechanoreception is the ability to sense and interpret mechanical stimuli such as pressure, sound waves and gravityMechanoreception is the ability to sense and interpret mechanical stimuli such as pressure, sound waves and gravitysound Chemoreception is the ability to sense and interpret chemical stimuli including taste, smell and chemical concentrationsChemoreception is the ability to sense and interpret chemical stimuli including taste, smell and chemical concentrations

9. Mechanoreception and Chemoreception The ear is a sensory organ that interprets auditory stimuliThe ear is a sensory organ that interprets auditory stimuli The parts of the ear help to collect sound, amplify sound and convert sound energy into nerve impulsesThe parts of the ear help to collect sound, amplify sound and convert sound energy into nerve impulsesparts of the earparts of the ear Hearing involves the conversion of mechanical energy into electrochemical impulsesHearing involves the conversion of mechanical energy into electrochemical impulsesHearing

10. Mechanoreception and Chemoreception Hearing loss can be due to:Hearing loss can be due to: 1.Birth defects 2.Ear infections Ear infectionsEar infections 3.Loud noises 4.Aging Aging

11. Mechanoreception and Chemoreception The inner ear is responsible the sense of balance and coordinationThe inner ear is responsible the sense of balance and coordination The semicircular canals detect head and body rotation (rotational equilibrium)The semicircular canals detect head and body rotation (rotational equilibrium)semicircular canalssemicircular canals The utricle and saccule detect movement of the head forwards and backwards (gravitational equilibrium)The utricle and saccule detect movement of the head forwards and backwards (gravitational equilibrium)

12. Mechanoreception and Chemoreception Proprioceptors are found in muscles and tendons and sense body positionProprioceptors are found in muscles and tendons and sense body position Taste is due to concentrated chemoreceptors in taste buds on the tongueTaste is due to concentrated chemoreceptors in taste buds on the tongue chemoreceptors Smell is due to concentrated chemoreceptors in olfactory bulbs in the nasal cavitySmell is due to concentrated chemoreceptors in olfactory bulbs in the nasal cavityolfactory bulbsolfactory bulbs

13. Mechanoreception and Chemoreception Touch is due to mechanoreceptors (touch, pressure, pain, temperature change) in the skinTouch is due to mechanoreceptors (touch, pressure, pain, temperature change) in the skinmechanoreceptors