B2.3.7 - Extinction Flashcards
What does extinct mean?
When all of the individuals in a species die out.
What are the adantages of making ‘gene banks’ of endangered organisms e.g. the black rhino?
- Tissue samples can be preserved/frozen and kept for a long time.
- One day scientists may have technology to clone them.
- Western Black Rhinoceros may have genes that are useful to human survival.
- Genes could be used for research.
- Genes could help other species of rhino to survive.
What evidence is there that specieis have gone extinct?
We find fossils of extinct species e.g. dinosaurs.
Give examples of situaitons that could lead to extinction.
Changes to an orgnaisms environment
Destruction of habitat
Outbreak of a new disease.
Introduction of new predaotrs/competition.
What is a gene bank?
A storage facility that stores genetic samples in case an organism goes extinct.
What is meant by an endangered species?
A species that only have a small population remaining.
What is a seed bank?
A gene bank that store seeds of different plants at low temperatures.
How can crop plants be preserved in a gene bank?
Pollen banks - pollen grains are stored
Cryobanks - seeds are stored at low temp. in liquid nitrogen.
Tissue banks - plant buds are stored.
Seed banks - dried seeds are stored at low temp.
What is meant by biodiversity?
The range of different organisms living in an area e.g. rainforest has high biodiversity; city has a low biodiversity.
What causes an organism to go extinct?
When they are unable to adapt to changes in their environment.
Give examples of drastic changes ot the environment that could lead to a mass extinction of many species.
Nuclear war
Meteorite impact
Supervolcano
