Sensitivity and coordinationPresentation Transcript
SENSITIVITY AND COORDINATION BY Seila matellan, Mario martin , Mario prieto and Celia martin
Stimuli and responses
A stimulus is anything that affects any of the body`s acivities.There are two types of stimuli: -Internal, they come from inside our bodies,like the feelings of hunger or thirst. External, these come from outside the body like the smell of a cake or the texture of a cloth
A responses is the body´s answer to a stimulus
Iternal receptors: They receive the internal stimuli our bodies produce.
External receptors: They receive external stimuli.They are in the sensory organs.
Muscular responses.These are movements the muscles make in response to a stimulus.
Glandular responses.These are when galnds produce various substances in response to a stimulus, like when you sweat.
The senses -Sight
The eye is the body´s organ for the sense of sight.The eye is made up of the eyeball and protected by the eyebrows, eyelids and eyelashes: When light reaches the eyeball, it goes through the cornea.Then it goes through the pupil then passes through the lens which focuses the image on the retina .
The ear is the body´s organ for the sense of hearing.The ear has three parts: -The outer ear. It is made up of the ear and outer auditory canal. -The middle ear it is made up of the eardrum and a chain of samll bones . -The inner ear. It is made up of the cochlea and the auditory nerve.
The body´s organ for the sense of touch is the skin. The skin is made up of three layers: -Epidermis It is the outer layer -Dermis It is under the epidermis -Hypodermis It is under the dermis
The senses-Smell and taste
The organ for the sense of smell is the nose. Receptors of smell are in the pituitary
The organ for the sense of taste is the tongue. Repetors for different flavours are in the taste buds.
The central nervous system
It has two parts -Brain it is inside the skull. It has three main parts: the cerebrum the cerebellum and the brain stem -Spinal cord it is a thick cord made up of many neurons that goes through the inside of the spine. It is protected by vertebrae.
The peripheral nervous system
It is made up of nerves -Sensory nerves -Motor nerves
Neurons are cells that belong to the nervous system.They are made up of three parts: a cell body, dendrites and axons
Voluntary and involuntary movements
Nerves carry sensory information to the brain which produces a response that moves through the motor nerves that transmit them to the muscles
The spinal cord controls the body´s reflexes which are involuntary.