B1.3

Question 1

What is a drug

Answer 1

Any chemical substance that changes how our body works

Question 2

What are the 5 main types of drugs and what do they do

Answer 2

Narcotics, make you sleepy
Painkillers block pain nerve impulses so no pain
Hallucinogens distort our senses and cause hallucinations
Stimulants reduce reaction time and increase time of neurotransmission across synapses
Depressants slow down activity of neurones making you more relaxed and increasing reaction time

Question 3

What is a carcinogen

Answer 3

Something that causes cancer

Question 4

Why is carbon monoxide dangerous

Answer 4

Reduces the capacity of red blood cells so less oxygen gets through the body. Also reduce size of blood vessels so even less blood and may cause tissue to die

Question 5

Why is smoking so dangerous

Answer 5

The smoke contains carbon monoxide and the tar has lots of carcinogens, and the tobacco smoke has lots of harmful chemicals that damage living tissue

Question 6

What causes cigarettes to be addictive

Answer 6

The nicotine in the tobacco and it can cause addiction which last years after just 4 cigarettes

Question 7

What are the short term effects of alcohol

Answer 7

Alcohol slows nerve impulses causing dizziness, slow reactions, blurred vision and worse coordination. Lots of it can cause unconsciousness and possible death from choking on vomira

Question 8

Long term effects of alcohol

Answer 8

Cirrhosis of the liver meaning liver doesn’t work properly and alcohol isn’t filtered out. Also cause brain damage affecting learning, memory and can cause blood clots. Also become addicted, alcoholics

Question 9

What is the main criteria for organ transplant

Answer 9

How well the tissues match
How similar age they are
How close together they are geographically
How I’ll and likely the patient is to survive the operation

Question 10

What other think affects organ donation

Answer 10

If it is ethically right, e.g. Giving a new liver to an alcoholic who may just destroy it again

Question 11

What ar the h four types of pathogens and examples

Answer 11

Bacteria: food poisoning
Viruses: measles, aids
Fungi: athletes foot
Protoctists: malaria

Question 12

How are pathogens spread and examples

Answer 12

Water, may contain bacteria
Vectors such as mosquitoes and houseflies
Food may contain dangerous bacteria
Contact, fungi spread by contact of skin
Airborne, viruses such as from sneezes
Body fluid, pathogens like hiv

Question 13

What is the difference between antiseptics and antibiotics

Answer 13

Antiseptics kill microorganisms outside the body, antibiotics destroy only bacteria and some fungi in the body

Question 14

What are the barriers humans have against pathogens

Answer 14

Tear glans make lysozyme that kill micro organisms
Nose hairs filter out dust
Mucus traps microorganisms and is swept out by cilia in the wind pipe
Skin forms scabs when there are cuts

Question 15

What are producers

Answer 15

Organisms such as plants that produce there own food

Question 16

What are primary consumers

Answer 16

Organisms that eat producers such as cows

Question 17

What are secondary consumers

Answer 17

Organisms that eat primary consumers, lions

Question 18

What are trophies levels

Answer 18

Levels of a food chain

Question 19

How is energy lost in food chains

Answer 19

Through living and respiration, heat

Question 20

How is energy transferred in food chains

Answer 20

The energy stored as biomass is the only energy that gets passed in

Question 21

Why doesn’t anything eat lions

Answer 21

There aren’t enough lions to support an animal that ate them so that organism would have to travel loads for each meal

Question 22

What is a pyramid of biomass

Answer 22

A pyramid showing the biomass per meter squared of each organism in a biomass pyramid

Question 23

What is parasitism

Answer 23

A relationship between two organisms where the parasite feeds and the host is its food

Question 24

Give examples of parasite

Answer 24

Head lice, fleas, tapeworms

Question 25

What is mutualism

Answer 25

A relationship between two organisms and they both benefit from it

Question 26

Give two examples of mutualistic relationships

Answer 26

Oxpeckers and ox, ox gets parasite removed and oxpecker gets food Cleaner fish and sharks, sharks get dead skin and parasites removed, cleaner fish get food

Question 27

What do nitrogen fixing do

Answer 27

They live in plant legumes and get protection, in turn they turn nitrogen into the air into nitrates which the plants need to produce proteins and grow

Question 28

What are chemosynthetic bacteria and what kind of relationship do they have with tubeworms

Answer 28

They are producers but rather than get energy from sunlight, they get it from chemical substances. Some of these bacteria live in giant tubeworms, the tubeworms gather the chemicals for the bacteria and feed from the products the bacteria make

Question 29

What do fertilisers contain and why

Answer 29

Nitrates and phosphates as plants need them to grow well

Question 30

Why was there rapid population growth in the nineteenth and twentieth century's

Answer 30

Because increases in food production, medication and better living conditions meant more people survived chiledhood and had children of there own who also survived

Question 31

Why is sulphur dioxide so dangerous

Answer 31

If it gets into the air, it will condense with water vapour and form sulphuric acid. This will rain and erode limestone paths, kill trees and acidity lakes so plant and animals can't liv in them

Question 32

What are indicator species and name 3 of them

Answer 32

Species that can be used to show us the presence of pollution, blackspit fungus in roses, bloodworms and lichens

Question 33

How can we use black spot fungus as an indicator

Answer 33

In polluted air with lots of sulphur dioxide, blackspot fungus dies

Question 34

How can lichens be used as an indicator

Answer 34

Some species of lichen live better than others depending on the air condition. E.g. Some live well with sulphur dioxide and others die

Question 35

How can we detect pollution in waters

Answer 35

Stonefly larvae and freshwater shrimps live in clean water with lots of oxygen, bloodworms and sludgeworms live well in polluted water as they're adapted to live in water with low oxygen levels

Question 36

How do plants remove carbon from the air

Answer 36

Take it in a co2 during photosynthesis, then the carbon atom becomes part of another molecule, glucose and the o2 is released. This glucose is either turned back into co2 during respiration or it will become other carbon molecules and become plant biomass

Question 37

What is the carbon cycle, starting from co2 in the air

Answer 37

Co2 in air is taken in by plants, these release some co2 in respiration. The rest of the carbon becomes biomass and is either eaten by other animals or it dies and is eaten by decomposers or becomes fossil fuel. If it becomes fossil fuel, eventually the co2 will be released in combustion back into the air. If decomposed, decomposers will release the co2 through respiration. If eaten, the animal will release it as co2 in respiration. Animal either becomes fossil fuel or is decomposed

Question 38

Why do plants need nitrogen and how do they get it

Answer 38

They need it to make proteins and grow, they can't use nitrogen in the air so need nitrogen compounds. Roots absorb nitrates in the ground

Question 39

Why do animals need nitrogen and how do they get it

Answer 39

They also need it to make proteins and also cant get it from the air. They need to get it from eating plants however some of the nitrates are lost in waste such as urea in urine.

Question 40

What role do decomposers have in the nitrogen cycle

Answer 40

They break down plants, animals and animal waste into ammonia and release it into the soil which plants can use

Question 41

Why are nitrogen fixing bacteria so important

Answer 41

They convert nitrogen in the air to ammonia for plants to use

Question 42

How is the relationship between plants and nitrogen fixing bacteria mutualistic

Answer 42

Plants provide shelter and protection for the bacteria in root nodules and the bacteria provide the plants with ammonia

Question 43

What do nitrifying bacteria do

Answer 43

Turn ammonia into nitrates which plants grow better with

Question 44

What do de nitrifying bacteria do

Answer 44

Convert nitrates in the soil into oxygen and nitrogen when there isn't enough oxygen in the soil such as when its waterlogged