B1

HideShow resource information
What are neurones and where are they carried?
They are specially adapted cells that can carry a nerve impulse, which is electrical in nature. This is carried in the axon.
1 of 42
What are the 3 types of neurone and what do each of them do?
1)A sensory neurone-carries nerve impulses from the receptors to the CNS. 2)A relay neurone-makes connections between neurones inside the brain and spinal cord. 3)A motor neurone-carries nerve impulses from the CNS to the muscles and glands.
2 of 42
State 3 adaptations that motor neurones have.
1)They are long to allow quick transfer of impulses around the body 2)Have branched endings(dendrites) to pick up impulses and pass to other neurones 3) an insulating sheath, which speeds up the electrical impulse.
3 of 42
Explain how an electrical impulse travels from 1 neurone to the next.
An electrical impulse travels along the axon causing the vesicles to move towards the membrane. They diffuse neutrotransmitters across the synapse. The chemicals the bind with receptor molecules in the next neurone which sets off a new electrical imp
4 of 42
What is the nervous system?
It allows organisms to react to their surroundings and coordinate their behaviour. The nervous system can be divided into the central nervous system and the peripheral nervous system. CNS=Brain + spinal cord PNS=connecting nerves.
5 of 42
What are receptors?
They are specialised cells that detect the stimulus using receptors, which generate nerve impulses.
6 of 42
What is a stimulus?
A stimulus is a change in the enviroment that we detect and respond to.
7 of 42
What are Effectors?
An effector is a muscle or gland that will bring about the response to a stimulus.
8 of 42
Explain what a voluntary action is.
They are under the conscious control of the brain, i.e. the person decides how to react to a stimulus.
9 of 42
Explain what a reflex action is.
They give fast automatic responses to a stimulus, helping to protect the body from harm.
10 of 42
Explain what Monocular vision is.
This means that part of their vision is seen by only one eye so they have a wider field of vision but it is harder to judge distance. This vision is usually found in prey.
11 of 42
Explain what Binocular vision is.
This means that part of their vision is seen by both eyes and it helps judge distance but you have a restricted field of vision. This vision is found in humans and usually found in predators.
12 of 42
Why does binocular vision help us to judge distance?
It helps us to judge distance as it produces 2 images. The brain compares both images. The more similar they are, the further away the further away the object is they are looking at.
13 of 42
What is accommodation?
Its where the eye focuses light by changing the shape of the lens.
14 of 42
Describe what happens when you look at a near object.
The ciliary muscles-contract, suspensory ligaments-go slack, lens-goes rounder, fatter and shorter, Light-refracts more.
15 of 42
Describe what happens when you look at a far object.
Ciliary muscles-relax, Suspensory ligaments-tighten, Lens-becomes thinner, Light-refract less.
16 of 42
State the function of the cornea.
The first part of the eye that light travels through and it refracts the light.
17 of 42
State the function of the pupil.
A hole that allows light into the eye in order to reach the retina.
18 of 42
State the function of the Optic nerve.
A sensory neurone that carries electrical impulses from the retina to the brain.
19 of 42
State the function of the Retina.
A layer of specialised cells found at the back of the eyeball. Contains photosensitive cells that detect light and colour and convert the energy into electrical signals that are carried to the brain.
20 of 42
State the function of the iris.
Made of muscle that contracts and relaxes in order to control the size of the pupil, therefore the amount of light entering it.
21 of 42
State the function of the lens.
The part of the eye that changes shape depending on what you are focusing on in order to refract light onto the retina.
22 of 42
State the function of the cilliary muscles.
They contract and relax to change the position of the suspensory ligaments which in turn help change the shape of the lens.
23 of 42
State the function of the suspensory ligaments.
Hold the lens in place and help in changing the shape of the lens.
24 of 42
What causes red-green colour blindness?
We see in colour because specialised cells in the retina detect red, green and blue light. In people with red-green colour blindness, some of these cells are missing. This is an inherited condition.
25 of 42
What is long sight and how is it caused?
Long sightedness is when you can see distant objects clearly but not close objects. It is caused by an eyeball that is too short, or by a lens that stays long and thin.
26 of 42
How can long sightedness be corrected?
It can be corrected by a convex lens which converges the light rays from close objects so that they focus on the retina.
27 of 42
What is short sight and how is it caused?
Short sightedness is when you can see near objects clearly but not distant objects. It is caused by an eyeball that is too long, or weak suspensory ligaments which cannot pull the lens into a thin, flat shape.
28 of 42
How can short sightedness be corrected?
It can be corrected by a concave lens which diverges the light rays so that they focus on the retina.
29 of 42
What are drugs?
They are chemicals that affect the way the body works. They can affect the mind or the body(or both) and are used for medicine and pleasure(recreational drugs). Some are legal(tobacco + alcohol) whereas others are illegal(ectasy + cocaine).
30 of 42
What effect do Depressants have on the body and give examples of them.
They slow down the brain's activity and the nervous system. Examples of depressants are: alcohol, solvents, temazepam.
31 of 42
What effect do Pain killers have on the body and give examples of them.
They Block nerve impulses. Examples of pain killers are: aspirin, paracetamol.
32 of 42
What effects do stimulants have on the body and give examples of them.
The speed up the brain's activity and the nervous system. Examples of stimulants are: nicotine, ecstasy, caffeine.
33 of 42
What effects do performance enhancers have on the body and give examples of them.
They enable muscle development. Examples of these are: anabolic steroids.
34 of 42
What effect do hallucinogens have on the body and give examples of them.
They distort what is seen and heard. Examples of these are: LSD, cannabis.
35 of 42
In the UK, illegal drugs are classified into 3 main categories. Explain how they are classified.
Drugs are classified into A, B and C. Class A drugs are the most dangerous and carry the highest penalties. Class C drugs are less dangerous and have lower penalties.
36 of 42
What happens to an addict when they stop taking the drugs they have been taking?
Because they have developed a tolerance to it and have been taking high doses of the drug, they can suffer withdrawal symptoms with both psychological(cravings) and physical(sweating, shaking, nausea) problems.
37 of 42
Describe the effects of alcohol and what is contained in it.
Alcohol contains ethanol which is a depressant causing slow reactions. Alcohol causes slurred speech, blurred vision, poor balance and vasodilation. It causes liver and brain damage in the long term.
38 of 42
What can excess alcohol lead to?
Unconsciousness, a coma or death and cirrhosis of the liver.
39 of 42
How many units of alcohol are there in a pint of normal strength beer, a large glass of wine or a double measure of spirits?
2 units.
40 of 42
What does tobacco smoke contain?
Tar, carbon monoxide, particulats and nicotine which is addictive.
41 of 42
What damage does smoking cause?
It damages the cilia lining the airways, so mucus, tar and dirt cannot be removed, causing smokers cough which damages alveoli causing emphay
42 of 42

Other cards in this set

Card 2

Front

What are the 3 types of neurone and what do each of them do?

Back

1)A sensory neurone-carries nerve impulses from the receptors to the CNS. 2)A relay neurone-makes connections between neurones inside the brain and spinal cord. 3)A motor neurone-carries nerve impulses from the CNS to the muscles and glands.

Card 3

Front

State 3 adaptations that motor neurones have.

Back

Preview of the front of card 3

Card 4

Front

Explain how an electrical impulse travels from 1 neurone to the next.

Back

Preview of the front of card 4

Card 5

Front

What is the nervous system?

Back

Preview of the front of card 5
View more cards

Comments

No comments have yet been made

Similar Biology resources:

See all Biology resources »See all Nervous system, hormones and behaviour resources »