CB4: Natural Selection and Genetic Modification

Question 1

What is evolution?

Answer 1

change over time

Question 2

Who came up with the idea of evolution by natural selection?

Answer 2

Charles Darwin

Question 3

Who was Wallace?

Answer 3

An Australian man with similar ideas to Darwin at a similar time

Question 4

What was Lamarkism?

Answer 4

the idea of evolution by acquired characteristics (animals change themselves). There’s no way to explain it.

Question 5

What is Darwinism?

Answer 5

the idea that evolution occurs by natural selection - survival of the fittest (those who suit or adapt to suit conditions will survive). Evolution is so slow you wouldn’t notice it. Thought the Earth was around 3.8bn years old - not too far off the truth.

Question 6

What is the tree of life?

Answer 6

The idea that all life comes from LUCA (last universal common ancestor)

Question 7

What is LUCA?

Answer 7

the Last Universal Common Ancestor

Question 8

What are the causes of extinction?

Answer 8

• competition
• environment
• diseases
• predators

Question 9

What did Darwin observe?

Answer 9

• living things produce more offspring than end up surviving
• population sizes are mostly constant
• variation
• characteristics are passed on

Question 10

phylogentic tree

Answer 10

“family tree” of evolution

Question 11

Extant

Answer 11

living species

Question 12

Extinct

Answer 12

dead species

Question 13

fossil evidence -> archaeology

Answer 13

very old -> old

Question 14

Closest relative to modern humans?

Answer 14

Homo Neanderthal/H. Neanderthal

Question 15

Common ancestor with H. Neanderthal?

Answer 15

H. Erectus

Question 16

What did H. Erectus evolve into in Europe, and what did they evolve into in Africa?

Answer 16

In Europe: H. Erectus -> H. Neanderthal
In Africa: H. Erectus -> H. Sapien

Question 17

Archaeology

Answer 17

Remains with bones.
Helps to work out behaviours (eg: diet from stool)

Question 18

What can teeth tell us?

Answer 18

what you ate

Question 19

What can footprints tell us?

Answer 19

Behaviour - footprints in volcanic ash

Question 20

What can brain size tell us?

Answer 20

brains were bigger, then they got smaller

Question 21

What is the study of classification?

Answer 21

Taxonomy

Question 22

Who invented classification?

Answer 22

Linnaeus

Question 23

Heirarchy

Answer 23

domain
kingdom
phylum
class
order
family
genus
species

Question 24

What are the domains?

Answer 24

archae, eukaryote, prokaryotes

Question 25

What’s the oldest domain?

Answer 25

Archae

Question 26

What are the kingdoms?

Answer 26

animals, plants, funghi, bacteria, protists

Question 27

How do we name organisms?

Answer 27

Genus species (eg: Homo erectus, H. erectus)

Question 28

What is convergent evolution?

Answer 28

When organisms evolve seperately to be similar

Question 29

How can we tell if things are the same species?

Answer 29

Can their offspring reproduce?

Question 30

What makes a plant a plant?

Answer 30

cellulose cell wall, photosynthesis

Question 31

What makes funghi funghi?

Answer 31

chitin cell wall, no photosynthesis

Question 32

What makes animals animals?

Answer 32

no cell wall, must eat

Question 33

What makes bacteria bacteria?

Answer 33

no nucleus

Question 34

artificial selection

Answer 34

selective breeding
can cause monoculture and health problems (eg: pugs’ breathing & bulldogs’ feet)

Question 35

What is monoculture and why can it be a problem?

Answer 35

When everything is the same
No variation - a disease could wipe out everything

Question 36

Genepool

Answer 36

all the alleles and genes within a breeding population

Question 37

tissue culture

Answer 37

taking plant pieces (cuttings) and growing larger versions of them (eg: lavender, roses)

This is a form of cloning

Question 38

Why can cloning plants be good?

Answer 38

• don’t need seeds or pollinators
• make whole plants from one cell
• useful for GM
• reduced chances of transmitting pests and diseases (produced in sterile containers)
• plants can grow which would struggle to reproduce naturally

Question 39

What is genetic engineering?

Answer 39

altering an organism’s genome

Question 40

Why can it be useful?

Answer 40

• protein can be produced synthetically
• insulin can be made synthetically (allows for Muslims and Jewish people to use it)

Question 41

What is a vector?

Answer 41

a plasmid carrying DNA from one cell to another

Question 42

How does genetic engineering work?

Answer 42

1. Restriction enzymes cut the DNA at specific sites
2. They leave complementary sticky ends where the bases are exposed
3. Ligase enzyme helps to stick it back together

Question 43

How is insulin made?

Answer 43

1. The gene which codes for insulin is cut from human DNA using a restriction enzyme
2. a plasmid is removed from a bacterial cell
3. the plasmic is cut with a specific and complementary enzyme (the same one which cut the human DNA). This leaves complementary sticky ends.
4. The sticky ends are joined with the enzyme ligase. A recombinant plasmid has just been made.