B2 Flashcards
What is the order of the groups of classification?
1) Kingdom
2) Phylum
3) Class
4) Order
5) Family
6) Genus
7) Species
What happens to the number of organisms in each group as you go down the list? (Towards Species)
As you move down the groups the number of organisms in each group will get smaller?
What are the two systems of classification?
1) Natural Classification.
2) Artificial Classification.
How does the artificial system of classification work?
It is a way of grouping organisms based on their physical traits.
How does the natural system of classification work?
The natural system is based on evolutionary relationships, animals which are closely related are in the same group.
How can scientists tell how closely together organisms are related?
Scientists can compare the DNA of organisms, to see how similar they are.
What is a species?
A species is a group of organisms which can interbreed to produce fertile offspring.
What is the current classification system called?
The current classification system is called the binomial system.
How does the binomial system work?
The binomial system splits the into two parts, the genus, and the species. The first name is the genus and the second is the species.
What is the main difficulty with classifying organisms?
Some organisms can be put into multiple groups along with the discovery of new organisms.
What is the main issue with classifying organisms by species?
Bacteria produce asexually so they can not be classified as a species.
What is a Hybrid organism?
A Hybrid organism is one which is produced through interbreeding of two different species. They can not produce fertile offspring.
What is an example of a Hybrid organism?
A Donkey is a common example of a Hybrid.
What do organisms in the same group normally have in common?
They normally share a common ancestor.
What are the two type of pyramids used to represent biological environment?
1) Pyramid of number.
2) Pyramid of biomass.
What is shown in a pyramid of biomass?
A pyramid of biomass represents the dry mass of living material at each stage in a food chain.
What is shown in a pyramid of number?
The number of organisms at each level in a food chain.
What two factors may cause a pyramid of biomass to look different to a pyramid of number?
1) If a producer has a very large mass.
2) If a small parasite lives on a large animal.
Why are Pyramids of biomass difficult to construct? (Two Reasons)
1) Some organisms feed on organisms from different trophic levels.
2) Dry mass involves killing the organism.
What three things can energy be wasted on when transferring energy between trophic levels?
1) Respiration.
2) Egestion.
3) Excretion.
What happens to the wasted energy between trophic levels?
It can be used by decomposers to start a new food chain.
What is the average percentage of lost energy between trophic levels?
90% is the amount lost normally between each level in a food chain.
What is the equation for efficiency between animals in a food chain?
energy useful / total energy * 100
What are the basic steps involved in the Carbon Cycle?
1) Carbon dioxide is removed from the air by plants.
2) Burning fuels and respiration releases carbon dioxide into the air.
3) Carbon dioxide is absorbed from the air by oceans
What are the basic steps of the Nitrogen Cycle?
- Nitrogen in the air coneverted into nitrates in the soil.
- Decomposers break down proteins in rotting plants and animals, into ammonia.
- Nitrifying bacteria turn ammonia in decaying matter into nitrates.
- Nitrogen-fixing bacteria turn atmospheric N2 into nitrogen compounds plants can use.
- Denitrifying bacteria turn nitrates back into N2 gas.
What is the role of Decomposers in the Nitrogen cycle?
To convert proteins into ammonia.
What is the role of Nitrifying Bacteria in the Nitrogen cycle?
Nitrifying Bacteria convert ammonia into nitrates.
What is the role of Denitrifying Bacteria in the Nitrogen cycle?
Denitrifying Bacteria converts nitrates into nitrogen gas.
What two conditions do decomposers need to keep working?
1) Oxygen
2) A suitable PH
When does competition occur between organisms?
Competition occurs between similar species in the same habitat.