B1.3 Flashcards
What is a drug
Any chemical substance that changes how our body works
What are the 5 main types of drugs and what do they do
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
What is a carcinogen
Something that causes cancer
Why is carbon monoxide dangerous
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
Why is smoking so dangerous
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
What causes cigarettes to be addictive
The nicotine in the tobacco and it can cause addiction which last years after just 4 cigarettes
What are the short term effects of alcohol
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
Long term effects of alcohol
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
What is the main criteria for organ transplant
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
What other think affects organ donation
If it is ethically right, e.g. Giving a new liver to an alcoholic who may just destroy it again
What ar the h four types of pathogens and examples
Bacteria: food poisoning
Viruses: measles, aids
Fungi: athletes foot
Protoctists: malaria
How are pathogens spread and examples
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
What is the difference between antiseptics and antibiotics
Antiseptics kill microorganisms outside the body, antibiotics destroy only bacteria and some fungi in the body
What are the barriers humans have against pathogens
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
What are producers
Organisms such as plants that produce there own food
What are primary consumers
Organisms that eat producers such as cows
What are secondary consumers
Organisms that eat primary consumers, lions
What are trophies levels
Levels of a food chain
How is energy lost in food chains
Through living and respiration, heat
How is energy transferred in food chains
The energy stored as biomass is the only energy that gets passed in
Why doesn’t anything eat lions
There aren’t enough lions to support an animal that ate them so that organism would have to travel loads for each meal
What is a pyramid of biomass
A pyramid showing the biomass per meter squared of each organism in a biomass pyramid
What is parasitism
A relationship between two organisms where the parasite feeds and the host is its food
Give examples of parasite
Head lice, fleas, tapeworms
What is mutualism
A relationship between two organisms and they both benefit from it
Give two examples of mutualistic relationships
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
What do nitrogen fixing do
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
What are chemosynthetic bacteria and what kind of relationship do they have with tubeworms
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
What do fertilisers contain and why
Nitrates and phosphates as plants need them to grow well
Why was there rapid population growth in the nineteenth and twentieth century’s
Because increases in food production, medication and better living conditions meant more people survived chiledhood and had children of there own who also survived
Why is sulphur dioxide so dangerous
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
What are indicator species and name 3 of them
Species that can be used to show us the presence of pollution, blackspit fungus in roses, bloodworms and lichens
How can we use black spot fungus as an indicator
In polluted air with lots of sulphur dioxide, blackspot fungus dies
How can lichens be used as an indicator
Some species of lichen live better than others depending on the air condition. E.g. Some live well with sulphur dioxide and others die
How can we detect pollution in waters
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
How do plants remove carbon from the air
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
What is the carbon cycle, starting from co2 in the air
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
Why do plants need nitrogen and how do they get it
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
Why do animals need nitrogen and how do they get it
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.
What role do decomposers have in the nitrogen cycle
They break down plants, animals and animal waste into ammonia and release it into the soil which plants can use
Why are nitrogen fixing bacteria so important
They convert nitrogen in the air to ammonia for plants to use
How is the relationship between plants and nitrogen fixing bacteria mutualistic
Plants provide shelter and protection for the bacteria in root nodules and the bacteria provide the plants with ammonia
What do nitrifying bacteria do
Turn ammonia into nitrates which plants grow better with
What do de nitrifying bacteria do
Convert nitrates in the soil into oxygen and nitrogen when there isn’t enough oxygen in the soil such as when its waterlogged
