Variation Flashcards
What main characteristic do organisms in the Chordata phylum have in common
Have a back bone, are invertebrates
Briefly describe characteristics of organisms in the animal kingdom
Heterotrophs (can't make their own food so have to eat plants other animals etc.) Multicellular Have a nucleus Don't have cell walls Can't make chlorophyll
What do all vertebrates have in common
Have a backbone and internal skeleton
What does oviparous mean? Name a group of vertebrates that are oviparous
They lays eggs and their offspring develop within the egg
Reptiles
What is a species
A species is the classification stage that holds the most similar organisms i.e. Humans
What is the name for offspring of two different species
Hybrid
In the binomial naming system each organism is given a two part name. What does each part refer to?
The genus and the species
Other than the environment what causes variation
Genetic variation
List three features which aren’t affected by environment and three which are
Eye colour
Natural hair colour
Blood type
Weight
Language
Religion
What is continuous variation
Vary within a range with no distinct categories
What is discontinuous
Two or more distinct categories
Give an example of a feature in humans where there is a)discontinuous b) continuous
A) height
B) blood type
Explain two ways that polar bears are adapted to living in the polar regions
Thick layer of flubber to insulate
Small surface area (small ears) to reduce heat loss
Explain darwins theory of natural selection
There is always variation within a species
Some populations have to compete with each other to survive
The individuals with characteristics that help them to survive are going to survive in order to reproduce and pass on these helpful adaptations
The ones who aren’t best adapted will die before reproducing
What is speciation
Speciation is where somehow a species becomes split, natural disaster for example. The two halves of the species then live in different habitats (one hot one cold)
The species adapt to fit their new surrounds but can adapt so much dependant on how different the surroundings that they do not represent the original species that was split
This means a new species is created
