Coordination and Response Details Flashcards
Electrical impulses travel along…
neurons
Parts of the mammalian nervous system
-Central nervous system(CNS)
-Peripheral nervous system(PNS)
Components of the central nervous system(CNS)
-Brain
-Spinal cord
Components of the peripheral nervous system(PNS)
Nerves(outside of the brain and spinal cord)
Role of the nervous system
Coordination and regulation of body functions
Components of a simple reflex arc(in order)
Receptor → Sensory neuron → Relay neuron → Motor neuron → Effector
Function of a synapse
Ensures the single direction of the transmission of neurons
Structure of a synapse
-Presence of vesicles containing neurotransmitter molecules
-Synaptic gap
-Presence of receptor proteins
Events at the synapse
-An impulse stimulates the release of neurotransmitter molecules from vesicles into the synaptic gap
-The neurotransmitter molecules diffuse across the gap
-Neurotransmitter molecules bind with receptor proteins on the next neuron
-An impulse is then stimulated in the next neuron
Function of cornea
Refracts light
Function of iris
Controls how much light enters the pupil
Function of lens
Focuses light unto the retina
Function of retina
Contains light receptors called rods(responsible for night vision) and cones(responsible for colour vision)
Function of optic nerve
Carries impulses to the brain
Features of fovea
-Area of the retina
-Where most of the light is focused on
-Has a highest density of cones
Function of rods
Greater sensitivity to light for night vision
Function of cones
Absorbing light of different colours for colour vision
Role of the pupil reflex
Appropriately controls the level of light that enters the eye
In bright conditions, pupils become…
smaller
In dim conditions, pupils become…
larger
Nature of the movement of circular and radial muscles in the iris
Antagonistic
What happens to the pupil in bright light(regarding circular and radial muscles)
-Circular muscles contract
-Radial muscles relax
-Pupil becomes constricted(smaller)