Body Co-ordination Flashcards
Optic Nerve
Carries the electrical signals from the retina to the brain
Lens
Enables light to be focused on the Retina
Cornea
Bends light into lens, in front of the iris
Iris
The coloured part of the eye, contains the dilator and sphincter muscles. The muscle contracts and opens to control the amount of light let in.
Pupil
An opening in the iris that determines the amount of light that enters.
Retina
Absorbs light rays and turns them into electrical signals
Chemoreceptors
Sensitive to chemicals (tongue) e.g food
Thermoreceptors
Sensitive to temperature (fingers) e.g Summer (hot) and winter (cold)
Photoreceptors
Sensitive to light (eyes)
Mechanoreceptors
Sensitive to touch (fingers) e.g rough, smooth
What happens in an involuntary response?
- Stimulus- whatever happens to the body to start the reaction
- Stretch Receptors - the receptors in the effected area send off a signal
- Sensory Neurones carry the signal from the Receptors
- Connector Neurones connect to Motor Neurones in spinal cord
- Motor Neurones - carry the message to the EFFECTOR
- Response/Reaction
Central Nervous System
Brain and Spinal Cord, receives messages from all over the body. Examines these messages and tells the body what to do.
Peripheral Nervous System
Made up of sensory receptors and nerves. Made up of two different systems. Somatic Nervous System and Autonomic Nervous System
Somatic Nervous System
Collects information through sensory organs, coordinates movement of the body, made up of sensory neurones and motor neurones
Autonomic Nervous System
Made up of two systems - Sympathetic Nervous System, speeds up functions
Parasympathetic Nervous System, slows everything down, the system in control when you are sleeping
Motor Neurones
Send information away from CNS to effector organs/muscles
Sensory Neurones
Send information to the CNS from effector organs/muscles
Reflex
An involuntary or automatic action that your body does in response to something
Hormone
Act as messengers in the body, co-ordinate our organs, made by endocrine glands, released into blood stream, stabalise our bodies internal environment
Endocrine system
All the glands throughout our body. Coordinated by the pituitary gland which responds to orders from the hypothalmus
Hypothalmus
Located in lower central part of brain, tell the pituitary gland whether to create or stop creating hormones
Pituitary Gland
Located in base of brain. Considered the most important part of the endocrine system. It makes the hormones that control other glands
Thyroid
Located near voice box, produces thyroxine which regulates the bodies overall metabolism
Parathyroid
Attached to thyroid, produces parathyroid hormones which regulate the level of calcium in the body