Chapter B10- The Human Nervous System Flashcards
What does Homeostasis maintain?
What three functions does this include maintaining?
What two responses may these automatic control systems involve?
What are receptors?
What are stimuli?
What are coordination centres and what do they do?
Give all three examples of coordination centres?
What do effectors, muscles or glands do?
What three things do all control systems include?
What does the human nervous system enable humans to do?
Where does the information from receptors pass along to (in detail)?
What are the two central nervous systems in the body?
What does the central nervous system (CNS) do?
What are the two forms of these?
Optimal conditions for enzyme action and all cell functions
- Blood glucose concentration
- Body temperature
- Water levels
Nervous or chemical responses
Cells which detect stimuli
Changes in the environment
They receive and process information from receptors
Such as the brain, spinal cord and pancreas
They bring about responses which restore optimum levels
Receptors; coordination centres; effectors, muscles or glands
Enable humans to react to their surroundings and to coordinate their behaviour
Passes along cells (neurones) as electrical impulses to the central nervous system (CNS)
The brain and the spinal cord
Coordinates the response of effectors
These effectors may be in the form of muscles contracting or glands secreting hormones.
What two things are reflex actions?
What part of the brain do they not involve?
What type of cell is a receptor?
What happens if a receptor detects a stimulus?
Where is this created?
What type of cell is this?
Where does this cell carry the impulse to and why?
In what order does this process of detecting a stimuli happen?
Automatic and rapid
The conscious part of the brain
Specialised cell
It will create an electrical impulse
In an attached nerve cell (neurone)
A neurone which is also specialised
To the co-ordinator (CNS) for a response
Stimulus—Receptor—Coordinator—Effector (muscle or gland)—Response.
What are sensory neurones?
What are motor neurones?
What are inter/relay neurons?
Where are hearing/balance receptors found?
Where are chemical receptors found?
Where are sensory receptors found?
What type of neurone are all receptors attached to?
What are the four type of receptor cells found in the skin?
What are the three main parts of a neurons structure?
Attached to your senses
Attached to your muscles
Connect the sensory to motor neurons
In the ears
In the nose
In the skin
A sensory neurone
Pain, pressure, temperature and touch receptors
Cell body, nucleus and axon.
What is a synapse (in detail)?
What are/do neurotransmitters do?
How do they do this?
What types of energy does this process change from?
What happens once the neurotransmitters are received by the neurone?
What is the reflex arc?
What is a reflex action (in detail)?
What are all sensory neurones connected to and how?
The gap (fluid filled) between two neurones
Allow the electrical impulse to cross the synapse (they are chemicals)
By crossing the gap from one neurone to another
Electrical energy—Chemical energy
The electrical impulse is recreated and passed on
The nerve pathway which makes a fast, automatic response possible
Signals that are passed directly from a sensory neurone, via a relay neurone, to a motor neurone for instant unthinking action
To all sense organs via receptor cells.
What happens in an emergency if a receptor cell detects a change in the environment?
What are these three neurones?
What is accommodation?
What three things occur to the ciliary muscles, suspensory ligaments and the lens to focus on a near object?
What is short sightedness and describe it?
What three things occur to the ciliary muscles, suspensory ligaments and the lens to focus on a distant object?
What is long sightedness and describe it?
What happens in these two common defects of the eyes?
The brain is missed out as a coordinator and the impulse travels along three neurones only
Sensory, relay (intermediary) and motor neurones
The process of changing the shape of the lens to focus on near or distant objects
The ciliary muscles contract; the suspensory ligaments loosen; the lens is then thicker and refracts light rays strongly
Myopia (unable to focus on distant objects)
The ciliary muscles relax; the suspensory ligaments are pulled tight; the lens is then pulled thin and only slightly refracts light rays
Hyperopia (unable to focus on near objects)
The rays of light do not focus on the retina.
In what way can short and long sightedness be treated and how does it do this?
What are three new technologies that help fix long and short sightedness?
What is the tough white outer layer of the eye called?
What and where is the cornea and what does it do?
What is the iris?
What is the centre of the eye called?
What does the iris contain and what does this allow for it to control?
With spectacle lenses which refract the light rays so that they do focus on the retina
Hard and soft contact lenses; laser surgery to change the shape of the cornea and a replacement lens in the eye
Sclera
The transparent outer layer found at the front of the eye. It refracts (bends) light into the eye
The coloured part of the eye
Pupil
Muscles that allow it to control the diameter of the pupil and therefore how much light enters the eye.
What does the lens do?
What are the two types of cells in the retina?
Which one of these cells detect black and white?
Which one detects colour?
What do both of these cells do?
What is the blind spot?
Why is this?
What does the optic nerve do?
What is the aqueous humour?
It focuses light onto the retina
Rods and cones
Rods
Cones
They turn the picture created into an electrical message for the brain
This is a bit of the retina which is not sensitive to light
Because there are no rods or cones there
Sends/carries electrical impulses from the receptors on the retina (cones and rods) to the brain
The watery stuff that fills the front of the eyeball.
What is the vitreous humour?
Why is this liquid clear?
What are the ciliary muscles?
What do they do?
What type of lens cure myopia and describe the shape?
What type of lens cure hyperopia and describe the shape?
What do myopia lenses do?
What do hyperopia lenses do?
What happens when a muscle contracts?
What three things occur in myopia?
What three things occur in hyperopia?
Where are the images of distant objects brought into focus in myopia?
Where are the images of near objects brought into focus in hyperopia?
The thicker jelly like liquid which fills the larger part of the eyeball and keeps it in shape
So that light can pass through it
These are a circle of tiny muscles around the lens
They change the shape of the lens by squeezing and relaxing
Concave lens (lens which curve inwards)
Convex lens (lens which curve outwards)
Pushes the light rays apart
Pushes the light rays together
It gets shorter and thicker
In myopia, the lens is in the wrong shape and refracts the light too much or the eyeball is too long
In hyperopia, the lens is in the wrong shape and doesn’t refract (bend) the light enough or the eyeball is too short
In myopia, the images of distant objects are brought into focus in front of the retina
In hyperopia, the images of near objects are brought into focus behind the retina.
What is the cerebral cortex?
What five functions does the cerebral cortex control?
Where is the cerebellum located in the brain?
What three functions does the cerebellum control?
What does the brain stem refer to?
What is another name for the brain stem?
What are the three functions that the brain stem controls?
What/where is the hypothalamus located?
What are the four functions that the hypothalamus controls?
How does the hypothalamus control the first function?
What is the hippocampus?
What are the two functions that the hippocampus controls?
A sheet of tissue that makes up the outer layer of the brain
Thought; voluntary movement; language; reasoning and perception
It is located behind the brain stem
Movement; posture and balance
The area of the brain between the thalamus and spinal cord
The medulla
Breathing; heart rate and blood pressure
Composed of several different areas and is located at the base of the brain
Body temperature; emotions; hunger and thirst
The hypothalamus detects changes in body temperature and sends commands to adjust the temperature
One part of the limbic system
Learning and memory.
In what two ways can the brain be investigated by and why?
Why is surgery on the brain difficult?
What can this easily cause?
What are sensory neurones?
What are the type of receptors found in the nose and tongue?
How is a nerve signal (electrical impulse) transferred across a synapse?
What is the eye and what does it contain (definition in detail)?
- By electrically stimulating parts of the brain to see what effect this has
- By using a Magnetic Resonance Imaging (MRI) scan to see which part of the brain has been affected after an accident
It is not fully understood what each area of the brain actually does
Unintended damage
Cells that carry impulses from the sense organs to the central nervous system (CNS)
Chemoreceptors
The nerve signal is transferred by chemicals which diffuse (move) across the gap
A sense organ containing receptors sensitive to light intensity and colour
