B4 Natural Selection and Genetic modification

Question 1

explain natural selection - survival of the fittest.

Answer 1

1. new alleles arise through mutations in DNA.
2. competition, predation, disease act as selection pressures
3. those with better characteristics are have a better chance of survival and pass on genes.
4. some individuals are less well adapted and will die off quicker
5. over a period of time the beneficial characteristics are passed through the generation

Question 2

who came up with the idea of evolution

Answer 2

alfred russel wallace
charles darwin

Question 3

what technique can be used to estimate how old a fossil is?

Answer 3

carbon dating

Question 4

list the different type of homo species

Answer 4

homo habilis
homo erectus
homo neanderthalensis
homo sapiens

Question 5

describe how the development of stone tools helped provide evidence for human evolution

Answer 5

the structures gradually became more complex and sufficient for carrying out certain tasks.

Question 6

explain how you can date the age of a tool.

Answer 6

rock - use stratigraphy, the deeper the rock layer is the older it is as younger rock layers submerge it
tool - use carbon dating, looking at the radioactive decay of the wood or fur an tell us how long ago it was made.

Question 7

what is a pentadactyl limb?

Answer 7

a limb with 5 digits, this can be seen in a number of organisms suggesting they come from a common ancestor.

Question 8

list the five kingdoms.

Answer 8

animals
plants
fungi
prokaryotes
protists

Question 9

describe the binomial naming species

Answer 9

HOMO SAPIEN
genus= homo
species= sapien

Question 10

list the three domains

Answer 10

archaea - primitive bacteria in extreme environments
bacteria - true bacteria
eukaryota - organisms who have a nucleus enclosed in membranes - fungi, plants, animals