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0
Q

What problems are there with the basing the idea of a species on their reproduction?

A

Some different species can reproduce to make hybrids.

1
Q

What is the general definition of a species?

A

reproduce with each other to produce fertile offspring.

2
Q

What problems are there with the basing the idea of a species on their anatomy?

A

Dog breeds all look very different but are in fact the same species. Also some species have males and females that look different.

3
Q

What is the binomial classification system?

A

Using 2 Latin names - the Genus and the species.

4
Q

How can the binomial classification system help to target conservation efforts?

A

It allows accurate identification of individual species wherever they are. For example: a robin in the UK isn’t the same as a robin in America so by using the binomial name “Turdus Migratorius” (american robin) and “Erithacus Rubecula” (UK robin) there is no confusion.

5
Q

How is classification complicated by ring species?

A

Neighbouring populations of species (e.g. gulls) may have slightly different characteristics but can still interbreed as part of a chain (next to each other) but the two ends of the chain can’t interbreed.

6
Q

How are polar bears adapted to their Arctic habitat?

A

A white appearance, as camouflage from prey on snow and ice

thick layers of fat and fur for insulation from the cold

A small surface area to volume ratio, to minimise heat loss

A greasy coat, which sheds water after swimming.

7
Q

In natural selection, what does variation refer to?

A

Most populations of organisms contain individuals which vary slightly from one to another.

8
Q

In natural selection, what does overproduction refer to?

A

Most organisms produce more young than will survive to adulthood.

9
Q

In natural section, what does the struggle for existence refer to?

A

Because populations do not generally increase rapidly in size there must therefore be considerable competition for survival between the organisms.

10
Q

In natural selection, what does survival of the fittest refer to?

A

Those with advantageous characteristics (the more likely to get mates/food/escaping predictors) are the more likely to survive the struggle

11
Q

In natural selection, how are advantageous characteristics inherited?

A

Better adapted organisms are more likely to reproduce successfully passing on the advantageous genes to their offspring.

12
Q

In natural selection, what happens gradually over time?

A

The proportion of individuals with the advantageous characteristics in the population increases compared with the proportion of individuals with poorly adapted characteristics, which may eventually be lost.

13
Q

Give 2 examples of continuous variation.

A

Height, weight, foot length, (there is a range from high to low in population.

14
Q

Give 2 examples of discontinuous variation.

A

gender
blood group (A, B, AB or O)
Eye colour
(There are not in between values)

15
Q

What are the 2 causes of variation?

A

Genetic or environmental.

16
Q

What does genetic variation mean?

A

Different characteristics as a result of mutation (changes in the DNA) or sexual reproduction (Shuffling up of chromosomes)
e.g. eye colour.