B1.3 Inter-relationships

Question 1

What is a drug?

Answer 1

A drug is a chemical substance, such as a narcotic that affects the CNS.

Question 2

Why can you buy some legal drugs at a pharmacy shops but need a prescription for others?

Answer 2

Many drugs can be dangerous if used incorrectly so they are restricted.

Question 3

What is an addiction?

Answer 3

When you have a physical need for something and get withdrawal symptoms if you do not get that substance.

Question 4

What is tolerance?

Answer 4

When your body gets used to a drug and you need a higher dosage to get the same effect.

Question 5

What does a depressant do and what is an example?

Answer 5

A depressant, such as alcohol, decreases the activity of the brain. It slows down responses and increases reaction times.

Question 6

What does a stimulant do and what is an example?

Answer 6

A stimulant, for example nicotine or caffeine, increases brain activity. It increases the number of neurotransmitters at synapses and does the opposite of a depressant.

Question 7

What does a painkiller do and what is an example?

Answer 7

A painkiller, for example morphine, decreases the feeling pf pain by blocking nerve impulses in the brain.

Question 8

What does a hallucinogen do and what is an example?

Answer 8

A hallucinogen, for example LSD, distorts what see and feel by altering the pathways that nerve impulses normally travel along.

Question 9

What is a reaction time?

Answer 9

The time you take to respond to a certain stimulus. It is often less than a second.

Question 10

Why is smoking tobacco harmful?

Answer 10

It contains carbon monoxide, which stops haemoglobin carrying enough oxygen
Tobacco contains carcinogens, like tar, which causes cancer
It is addictive due to the nicotine.

Question 11

What are the short term effects of drinking alcohol?

Answer 11

It slows your reactions
Blurred vision
Lowered inhibitions- which can lead to you doing dangerous things.

Question 12

What are the long term effects of drinking alcohol?

Answer 12

Cirrhosis of the liver- this is when liver cells die as a result of too much alcohol and they are replaced by scar tissue, which blocks the blood flow
Brain damage.

Question 13

What is an organ transplant?

Answer 13

When a healthy organ taken from a donor and used to replace a damage organ in a patient.

Question 14

Why are there big ethical issues surrounding organ transplants?

Answer 14

There is a shortage of donor organs - so only some people will get a transplant. This creates a dilemma of who gets a transplant and who has to die.

Question 15

What factors may influence who gets an organ transplant and who doesn’t?

Answer 15

Age
Family
If they need a transplant due to their actions, or something out of their control
Benefits of the transplant.

Question 16

What are pathogens?

Answer 16

Micro-organisms that can spread diseases.

Question 17

What are the 6 ways in which a disease can be spread?

Answer 17

Water
Food
Air
Contact
Body fluids
Animal vectors

Question 18

How are pathogens transmitted in water and what is an example of a disease?

Answer 18

Pathogens that cause cholera live in water and it is spread when drinking water is contaminated with the diarrhoea of sufferers.

Question 19

How are pathogens transmitted in food and what is an example of a disease?

Answer 19

Pathogens are picked up by eating contaminated food eg salmonella.

Question 20

How are pathogens transmitted in the air and what is an example of a disease?

Answer 20

Airborne pathogens are carried in air in droplets produced when you cough or sneeze and other people breathe them in. An example is the influenza virus.

Question 21

How are pathogens transmitted on contact and what is an example of a disease?

Answer 21

They are picked up when you touch a contaminated surface eg athletes foot.

Question 22

How are pathogens transmitted in body fluids and what is an example of a disease?

Answer 22

They are in the body fluid and spread to the next person when they come into contact with the fluid. Examples are: 
Blood
Breast milk
Semen
An example of a disease is HIV

Question 23

How are pathogens transmitted by animal vectors and what is an example of a disease?

Answer 23

The animal vector infects humans with the disease. An example is malaria, which is spread by the anopheles mosquito.

Question 24

What barriers does the body have against pathogens?

Answer 24

The skin is a physical barrier
The respiratory tract has mucus which traps pathogens and cilia which transport the mucus away
They eyes produce bacteria killing enzymes
The stomach contains hydrochloric acid which kills most pathogens.

Question 25

How do plants defend themselves against pathogens?

Answer 25

They produce chemicals which can have an antibiotic like effect on the pathogen. An example is the tea tree in Australia, which produces and oil which is now used in products like facial cleansers.

Question 26

What is an antiseptic?

Answer 26

Chemical substances that stop pathogens getting into the body?

Question 27

What are antibiotics?

Answer 27

Chemical substances that kill or prevent the growth of bacteria or fungi.

Question 28

How do bacteria become resistant to antibiotics?

Answer 28

One has a mutation making it resistant. All the others die out and that one survives and reproduces. Then all of the bacteria are resistant.

Question 29

Why do bacteria develop resistance?

Answer 29

From overuse of antibiotics.

Question 30

What is a food web?

Answer 30

The interdependence of animals in a habitat for survival.

Question 31

What do the arrows in a food web show?

Answer 31

The direction that the energy travels in.

Question 32

How is energy released in an animal?

Answer 32

Remains as biomass in faeces Transferred as heat to the surroundings Stored as biomass

Question 33

How is energy lost in a plant?

Answer 33

Lost as heat Reflected back to the surroundings Stored as biomass

Question 34

What is the pyramid of biomass?

Answer 34

A pyramid that shows the biomass of organisms in a area.

Question 35

What is a parasitic relationship?

Answer 35

Where a parasite feeds of its hosts.

Question 36

What are some examples of parasites?

Answer 36

Fleas Head Lice Tapeworms

Question 37

What is a mutualistic relationship?

Answer 37

When two organisms, mutualists, benefit each other.

Question 38

What is an example of a mutualistic relationship?

Answer 38

Oxpeckers and large herbivores. The oxpeckers eat parasites off of the herbivore, so they get food, and the herbivore gets rid of parasites.

Question 39

What are nitrogen fixing bacteria?

Answer 39

Bacteria that live in the roots of legumes and turn nitrogen into nitrogen compounds. The bacteria are protected and the plants gain food.

Question 40

What are the potential problems of a greater population of humans?

Answer 40

Raw materials are being used up More waste is produced More pollutants are being produced

Question 41

What is eutrophication?

Answer 41

When nitrates and phosphates from fertilisers wash into rivers and lakes and kill the life there.

Question 42

What is the process of eutrophication?

Answer 42

1. Excess nitrates wash into river causing rapid growth of algae 2. Some plants start dying due to competition for light 3. Microbe numbers increase as they feed off the dead material 4. Fish and aquatic animals suffocate as the microbes use up all the oxygen.

Question 43

What are the benefits of recycling?

Answer 43

We use less raw materials It uses less energy Produces less waste

Question 44

What are some of the disadvantages of recycling?

Answer 44

It still uses energy Waste can be difficult and time consuming to sort through The equipment needed can be expensive The recycled product isn't as good quality Some materials can only be recycled a certain number of times.

Question 45

What are indicator species?

Answer 45

Species that cannot live in clean or polluted air or water. They are used to see pollution levels.

Question 46

What are some indicator species that indicate clean water?

Answer 46

Stonefly larvae | Freshwater shrimps

Question 47

What are some indicator species that indicate polluted water?

Answer 47

Bloodworms | Sludgeworms

Question 48

What indicator species indicate clean air?

Answer 48

Blackspot fungus

Question 49

What does the absence of an indicator species indicate?

Answer 49

The opposite to what the species indicates.

Question 50

In the carbon cycle, what is the only way that carbon dioxide is removed from the atmosphere?

Answer 50

Photosynthesis.

Question 51

What are the possible stages for a carbon atom in the cycle?

Answer 51

``` Fossil fuel Carbon dioxide Carbon compound in a plant Carbon compound in an animal Carbon compound in soil Carbon dioxide ```

Question 52

In the nitrogen cycle, how is nitrogen taken out of the atmosphere?

Answer 52

Lightning Nitrogen fixing bacteria in the soil Nitrogen fixing bacteria in roots.

Question 53

How are nitrates taken out of the soil?

Answer 53

Absorbed by roots | Denitrifying bacteria.

Question 54

What are the possible stages of a nitrogen atom in the cycle?

Answer 54

``` Nitrogen Nitrate in the soil Plant protein Animal protein Ammonia in urea Nitrate in the soil ```