3.4.5-3.4.7 Species Taxonomy And Biodiversity Flashcards
(43 cards)
What is a species?
A group of similar organisms that are able to reproduce to produce fertile offspring.
What is courtship behaviour?
Behaviours shown within species to ensure that a mate of the same species is attracted, and fertile offspring is produced.
Why is reproduction important?
Organisms must reproduce and pass on advantageous alleles to ensure the survival of their species.
Why is courtship behaviour important?
It synchronises mating behaviours (mating occurs when eggs are mature).
It encourages reproduction which is important to organisms as it allows a species to survive over time.
Each individual is able to ensure that their DNA is passed onto the next generation.
Females of most species only produce eggs at certain times (fertile) so need to alert males that they are ready to mate at these times.
It ensures mating is successful so offspring have maximum chance of survival by recognising their own species (species recognition).
What is a courtship ritual?
A sequence of actions which is unique to each species, which enables animals to identify members of their own species to reproduce with.
They are often performed by males, and females will observe the courtship ritual and decide if they want to mate with the male.
What is species recognition and why is it important?
Courtship behaviour that helps animals recognise their own species to ensure they mate with the same species.
This is important as it means they can produce fertile offspring.
What is mating compatibility?
Both partners need to be sexually mature, fertile and receptive.
Courtship behaviour can be used to identify when this is the case and so increase the success of mating.
What is pair-bond formation?
When the male and female stay together after mating to raise the offspring.
It increases the chances of the offspring’s survival by having two parents present.
What is synchronised mating?
Courtship behaviour that is shown or accepted when the eggs are mature, so there is maximum possibility of the sperm and egg meeting.
This increases the success of reproduction.
What is a stimulus response chain?
A sequence of courtship behaviours.
The stimulus is the courtship action from the male which acts as a stimulus for the female.
The response is when the female responds with a specific action that stimulates the male to carry out further action.
The ritual generates a chain of stimuli and responses, and the longer the chain is, the greater the chance of mating.
How do chains differ for different species?
Stimulus-response chains are the same for members of the same species but different for members of different species.
This means both individuals can identify that they are the same species and ready to mate.
Why is studying courtship sequences important?
The more similar a courtship sequence is between different species, the more closely related the two species are.
What is classification?
The grouping of organisms
What is the binomial system?
A way of naming species.
It is universal so means all scientists name species in exactly the same way.
Who created the binomial system?
Carl Linnaeus
How does the binomial system work?
The organisms first name is their genus and their second name is their species.
The names are printed in italics or underlined.
The first letter of the genus is uppercase but species is lowercase.
What is a genus?
A group of similar or closely related species.
Therefore if two species have the same genus, it shows they are closely related.
Why might different species look similar?
Due to natural selection and evolution.
If they live in a similar environment, they will have similar selection pressures.
This means similar alleles will have the same selective advantage.
This means similar/same proteins are produced and so the two different species have similar characteristics.
What do classification systems use?
A hierarchy
What is a hierarchy?
Smaller groups are placed within larger groups
There are no overlaps between groups
What are the taxa names in order?
Domain
Kingdom
Phylum
Class
Order
Family
Genus
Species
What are the 3 categories of domain?
Archaea
Prokaryotes
Eukaryotes
Why do we use classification systems?
So we can understand relationships between organisms and keep track of changes eg. Evolution
So the system is universal to globally keep track of organisms
How were organisms originally classified, and why is this not used now?
Based on visible similarities eg. Appearance
However, organisms from the same species may look different, or organisms from different species may look the same, meaning this method is not accurate.
