Topic 1 - Variation: classification Flashcards
How would you use a key to identify an unknown organism?
A key is a series of questions about the features of the organism. You use it to narrow down the options until you’re left with just one possible species.
What is the binomial classification system?
It’s a naming system which gives each species a two-part Latin name.
Why do ring species make classification difficult?
A species can be defined as a group of organisms that interbreed to produce fertile offspring. For a ring species, it’s hard to tell if all the populations are different species because the ones that live further apart can’t interbreed successfully, but the ones that live closer together can.
Why is it sometimes hard to put vertebrates into groups based on their features?
When the classification system was set up it was based on the animals and plants known at the time. Since then, new species have been discovered that fit into more than one group.
There are two kingdoms of unicellular living things. What are they called?
Protoctists and prokaryotes
What features do scientists use to divide vertebrates into groups?
How they absorb oxygen, how they reproduce and how they regulate their internal body temperature.
Describe the characteristics of the plant (plantae) kingdom.
Plants are multicellular, have chlorophyll, make their own food and have cell walls.
Describe the characteristics of the animal kingdom.
Animals are multicellular, don’t have chlorophyll, can’t make their own food and don’t have cell walls.
Give a difference between the protoctist kingdom and the prokaryote kingdom.
Protoctists have a nucleus and prokaryotes don’t.
What is a ring species?
It’s a group of related populations that live in neighbouring areas. The populations that live close to each other can interbreed to produce fertile offspring but the ones that live further apart can’t.
