Inter-relationships Flashcards
(24 cards)
Describe the harmful effects of the following chemicals in cigarette smoke
a) nicotine b) tar c) carbon monoxide
Nicotine is an addictive chemical and makes smoking addictive
Tar is a chemical that can lead to cancer
Carbon monoxide combines irreversibly with haemoglobin, this means red blood cells can carry less oxygen
How does a stimulant drug work. Give examples
A stimulant increased brain activity by increasing the amount of neurotransmitters at synapses
Nicotine and caffeine
State two long term affects of drinking too much alcohol
Liver failure
Brain damage
What is a pathogen
A pathogen is a harmful microorganism that cause disease
What is a vector
Vectors are animals that spread disease
Mosquitoes, house fly
State four ways that pathogens can be spread, give examples
In body fluids eg HIV
In water eg cholera
Skin contact eg athletes foot
In food eg salmonella
Name one chemical and one physical barriers against pathogens
The skin - effective Barrier
The stomach - HCl kills all pathogens
What do plants produce to defend themselves from bacteria
Produced chemical
What are antiseptics
Antiseptics are used outside the body to destroy or stop bacteria growing
Name two types of antibiotics
Antibacterials - stop bacteria
Antifungals - stop fungi
Name one type of bacteria that has developed resistance
MRSA is resistant to methicillin
Why shouldn’t your doctor give antibiotics for a mild infection
Giving antibiotics when not needed has increased the rate of developing resistance
Where does the energy in a food chain originate. What happens to the energy
The sun. The energy is lost in waste or passed on to the next organism
Why are pyramids of biomass always pyramid shaped
Because as you work up through the chain the mass goes down
What is the difference between a parasitic and mutualistic relationship
Parasitic- only one organisms benefits
Mutualistic - both organisms in the relationship benefit
Give an example of a parasitic relationship
Mistletoe
Grows on trees and uses all of the water and nutrients
Give an example of a mutualistic relationship
Cleaner fish
Eat dead skin and parasites off of larger fish
Get a food source and protection in exchange
Explain what eutrophication is
Eutrophication is when too much fertiliser is placed on a field
The fertiliser runs into lakes and rivers
This causes Algae to begin growing on the surface of the lake
Plants at the bottom of the lake can no longer get light to grow and begin to die
Microbes increase as they feed on the dead plants and use up all the oxygen
Fish die as there is no oxygen left for them
What does it mean if you find stone fly larvae in a river
The river is clean
Explain how lichen can be used as an indicator of air pollution
Lichen are sensitive to concentration of sulphur dioxide
If there are lots of lichen it means that the air is clean
Describe the carbon cycle
CO2 in the air is taken in by plants to photosynthesis, plants give carbon out by then respiring or dead plants decaying
Animals then eat these plants and so transfer some of the carbon into them, they then respire it back into the air or give it out when they decay
CO2 is released from decay
It’s also released when fossil fuels are burnt
Why is nitrogen needed by plants and animals
Nitrogen js needed for making proteins for growth
What do decomposers do
Break down dead plants and animals
Turn proteins into ammonia
Describe the nitrogen cycle
Lightning makes nitrogen react with oxygen to make nitrates
Nitrogen fixing bacteria turn N2 into nitrogen compounds
Decomposer bacteria turn proteins into ammonia
Nitrifying bacteria turn ammonia into nitrates
Denitrifying bacteria turn nitrates into nitrogen gas
Nitrates are in the soil by nitrogen fixing bacteria, plants absorb the nitrates, animals then eat the plants and get nitrates too.
Plants and animals decompose and decomposer bacteria turn nitrogen into ammonia
This ammonia is taken by nitrifying bacteria and turned back into nitrates
