Science Unit A Exam/ 4.0 Exam Flashcards
What are the definitions and differences between the terms threatened, endangered, and special concern?
Threatened- are likely to become endangered if their current declines are not reversed
Endangered- are in immediate danger of extinction or extirpation
Special Concern- are particularly vulnerable to change in their environment (natural events, human activities), because they are so specialized
What are the definitions and differences between the terms extinction and extirpation?
Extinction- the disappearance of every individual of a species from the entire planet
Extirpation- the local extinction or disappearance of a species from a particular area.
What are the natural causes of lowering biological diversity (extinction)?
- Catastrophic events (asteroids, volcanic eruptions, earthquakes)
- Lack of food due to overpopulation
- Disease
- Overspecialization
What are the unnatural causes of lowering biological diversity?
subcategories of one
- Habitat loss (urbanization, expansion of agriculture, expansion of forestry, pollution)
- Introduction of non-native species
- Overhunting
Are most extinctions/ extirpations a fast or slow process?
Most are a slow process, but sometimes mass amounts of environmental change can make the process quick
What is overspecialization, why does it occur, with an example?
Overspecialization refers to the adaptations that some organisms have that suit them to only a narrow set of environmental conditions
It most likely is a result of an organism living in a largely unchanging environment
Ex- Pandas only eat bamboo
Why can overspecialization be dangerous with an example?
These organisms will not be able to cope with environmental change well because they are so well suited to a very small set of factors
Ex- Pandas can’t switch over to another food source if their bamboo source is taken away (logging)
How do non-native species affect the native species of Canada?
When the non-native species are introduced, they begin to compete for resources (purple loosestrife)
What is the Dodo bird an example of and why?
Dodo birds are an example of extinction due to overspecialization because they were introduced to new predators that would hunt them and Dodo birds are not used to having predators hunting them in their environment
What is the difference between Artificial and Natural Selection?
Natural selection happens when the environment chooses which species get to last long enough to reproduce
Artificial Selection is when humans breed species for desirable traits they want in a species
Ex. Modern corn is a domesticated relative of a wild species of grass call teosinte, champion horses
What is genetic engineering, what process is oftentimes used, with an example?
The intentional altering of the DNA of an organism through technology. This often involves inserting one gene from one organism into another organism
Ex. Insulin is now created by bacteria that were genetically engineered to produce insulin. This was done by inserting the human insulin creating gene into the bacteria
What is cloning with an example?
The process of creating a genetically identical organism
Ex. Dolly the sheep was a clone of her mom
What is in vitro fertilization, and why is it favorable?
Sperm from a prize bull and eggs from a prize cow are put together in a lab, creating many little embryos. These embryos are then implanted in a different cow, so all the offspring will be brothers and sisters
This method is favored because breeders can determine the sex of the offspring to ensure they are all females
What is an example of non-heritable and heritable characteristics?
Examples of heritable characteristics are Skin, Blood, eye colors, and etc…
Examples of Non-heritable characteristics are: being a pro gamer among us, playing piano, and playing being able to be pro at baseball.
What is artificial insemination? What are its benefits?
Sperm are harvested from a prize bull and inserted into many females.
This method is often favored because it is cheaper, and provides a bit more variation in the offspring
What is in vitro fertilization?
Sperm from a prize bull and eggs from a prize cow are put together in a lab, creating many little embryos. These embryos are then implanted in a different cow, so all the offspring will be brothers and sisters
This method is favored because breeders can determine the sex of the offspring to ensure they are all females