Coordination Flashcards
What is stimulus?
change in environment around animal
What is response?
reaction to the change in environment (stimulus)
Which detect the change in environment?
Receptors organs
What is the organ that respond to stimulus?
Effector organs
What are the effector organs in human body?
Muscle
Glands
Stimulus —-> _____ —–> response
Receptor organ ——> CNS ——-> effector organq
Which connects the receptor and effector?
Coordination system or nervous system
How the information in the nerve cells is transmitted?
The information in the nerve cells is transmitted in the form of electrical signals called nerve impulses.
What is the role of receptor?
To detect the stimulus and convert its energy into electrical signals of nerve impulses.
What are human receptors and the energy they receive?
Eyes - light
Ears - sound, mechanical
Tongue - chemical
Nose - chemical
Skin - mechanical, heat
muscle - mechanical
How the impulses travel along neurone?
Impulses travel along neurones by the movement of charged particles in and out of the neurones.
What is the speed of impulses?
10 - 100 meters/ second
Where does impulses from receptors pass through?
Sensory neurone
What is central nervous system, CNS?
Brain and spinal cord
What is transmitted along motor neurone?
Nerve impulses from CNS are transmitted across motor neurone to the effector organ.
A typical nerve contains thousands of individual neurones.
True
Where is cell body of motor neurone located?
At one end of the fiber, in the CNS.
What is dendrons in motor neurone?
Cytoplasmic extension on the cell body are dendrons
What is synapses?
Junctions with other neurones on any part of cell body
What is axon in motor neurone?
Fiber that carries impulses to the effector organ
What does myelin sheath do?
It insulate the axon, preventing short circuit with other axons, and speed up the conduction of nerve impulses.
How does the myelin sheath form?
Myelin sheath is formed by the membranes of special cells wrap up around the axon as it develops.
What does nerve ending of axon connect with?
muscle fibers
Which neurone link sensory and motor neurones?
Relay neurone
What is sclera?
Sclera is the tough outer white part of the eye which protect the eye.
What is cornea?
Cornea is the transparent window formed by sclera at the front of the eye. it lets light into the eye.
What is cornea?
Cornea is the transparent window formed by sclera at the front of the eye. it lets light into the eye.
What is the name color ring of tissue behind cornea?
iris which control the size of the pupil
What is pupil?
Pupil is the black part or hole in the eye which allows light through, and it is black because there is no light escaping from the inside of the eye.
What is underneath the sclera?
choroid
Why choroid is dark?
Because it contain many pigments cells which prevent the reflection of light inside the eye.
What is retina and what is its function?
Retina is the innermost layer of the back of the eye, where the light energy is converted into electrical energy of nerve impulses.
What does retina contain?
It contains receptor cells (rods and cones) which respond to light and produce impulse in the sensory neurones
When do rod and cone cells work?
Rods works well at dim light but it can’t distinguish colors.
Cones works well at bright light and it can distinguish colors.
What are types of cones?
There are three types of cones which respond to different color of light (red, green, blue)
What is fovea in eye?
Fovea is the area at the center of retina where cones are particular concentrated.
Cones give sharper image than rods.
True
What is needed to form an image on the retina?
Light need to be refracted at the boundary of cornea and air and then at the lens.
What is the result of refraction at the cornea and lens?
Image on the retina became inverted, and the brain interpret it right way up.
What is the role of iris?
To control the amount of the light entering the eyes by controlling the shape of pupil.
What does iris contain?
Circular muscle
Radial muscle
What happen to the eye in bright and dim light?
In bright light, the circular muscle contract and radial muscle relax causing the pupil to constrict.
In dim light, the circular muscle relaxes and radial muscle contract, causing the pupil to dilate.
What is the purpose of iris reflex?
To allow the right intensity of light to fall on the retina.
What is blind spot?
Blind spot is an area in retina where there is no cones and rods, images cannot be formed at the place.
What is accommodation?
Accommodation is the changes that happen in the eye which allow us to see things at different distances.
Why the shape of lens can be change?
Because it is made up of cells which contain elastic crystalline protein.
What controls the shape of lens in the eye?
Ciliary muscle and suspensory ligaments
What does the inside of the eye fill with?
Transparent watery fluid which pushes outward on the eye.
How does the ray of light from near object and away object enter our eyes?
Light from away object are almost parallel when they enter our eyes.
Light from near objects are diverged when they enter our eyes.
What happen to eye when focusing to distance vision and near vision?
When focusing on distant object, our ciliary muscle relaxes and suspensory ligaments stretched and pull tight, flattening the lens.
When focusing on nearby object, our ciliary muscle contract, suspensory ligaments slacks, making the lens more convex.
What is reflex action?
Reflex action is the rapid and automatic response to the stimulus which often is to protect our body.
What is reflex arc?
Reflex arc is the nerve pathway of the reflex.
Why is grey matter has grey color and white matter has white color?
Grey matter at the middle of the spinal cord has grey color because it consist mainly of nerve cell bodies.
White matter has white appearances because it contains many axons with fatty myelin sheath.
Each neurons may form synapses with thousands of other neurone.
True
It is estimated that there are —– synapses in the CNS.
between 100 to 1000 million
What exactly are the synapses?
Gaps between two neurones.
What is the gap crossed by?
Chemical
What does impulses arriving at synapse result?
Impulses arriving at the synapse result branches at the end of the axons to secrete a chemical called neurotransmitter.
What happened to neurotransmitter after it has passed on the message?
It is broken down by the enzyme from the second neurone
How chemical from first neurones attach to the second neurone?
By diffusion
Why synapses are important for integrating information in the CNS.
In the CNS, nerve cells may have thousands of synapses with other neurones which means output of one cell may depend on the input of many cells add together.
Why it is easy for other chemicals to interfere with the working of the synapse?
Because they are worked by chemicals.
