SB4

Question 1

Who created the theory of speciation?

Answer 1

Wallace

Question 2

What is the theory of speciation?

Answer 2

1. Two populations of same species become isolated
2. Physical barriers separate populations
3. Populations adapt to new environments
4. New species is developed

Question 3

Define evolution

Answer 3

the change of inherited characteristics within a population over time

Question 4

What is Darwin’s theory of evolution

Answer 4

1. Mutations in DNA cause variation
2. Characteristics most suited to the environment survive
3. Characteristics are then carried down through generations

Question 5

How does antibiotic resistance occur - 4 steps

Answer 5

1. Random mutation occurs in bacteria
2. Creates a strain of bacteria
3. Those with antibiotic resistance survive, others don’t
4. Resisted bacteria replicate

Question 6

How does antibiotic resistance prove Darwin’s theory correct

Answer 6

Bacteria with advantgeous genes are more likely to survive and reproduceproducing more bacteria with that gene

Question 7

How can antibiotic resistance be reduced (3 points)

Answer 7

1. Completing the course of antibiotics
2. Avoid the overuse of antibiotics
3. Limit the use of antibiotics in agriculture

Question 8

Why do antibiotics not affect viruses

Answer 8

Lack of cell walls that can be attacked like bacteria does

Question 9

What do you call a bacteria resistant to most antibiotics, give an example

Answer 9

A superbug - i.e MRSA

Question 10

What is a method used to estimate when a fossil was made

Answer 10

Carbon dating

Question 11

How does Ardi provide evidence for evolution

Answer 11

She shows phenotypic traits of both humans and apes:
● Ape-like characteristics e.g. long arms, large big toes
● Human-like characteristics e.g. the structure of her bones suggests that she walked upright

Question 12

How does Lucy provide evidence for evolution

Answer 12

She shows phenotypic traits more human-like than that of ‘Ardi’:
● The structure of bones in her legs and feet are more adapted to walking upright than climbing
● However, her brain size is closer to that of an ape’s

Question 13

How does Leakey’s discovery of fossils from 1.6 million years ago provide evidence for evolution

Answer 13

Fossils of what’s now known as Homo habilis had a skeleton that of a modern human than either Ardi or Lucy

Question 14

How does the development of stone tools provide evidence for evolution

Answer 14

Homo habilis used Oldowan tools created by smashing rocks together - had simple uses like cracking nuts
Homo Neanderthals and Homo sapiens tools used pointed arrow heads and hooks allowed them to hunt

Question 15

How can we date tools using radiometric carbon dating

Answer 15

By observing the natural decay of the isotope carbon 14 estimations on half-life can provide an age

Question 16

How can we date tools by Stratifying rock layers

Answer 16

Looking at the layer of Sediment in which a rock was found and tracing that back to when it formed

Question 17

How does the pentadactyl limb provides evidence for evolution

Answer 17

seen in multiple organism it can show they all had a common ancestor and then differentiated due to selection pressures

Question 18

What are the three domain systems

Answer 18

● Bacteria
● Archaea
● Eukaryota

Question 19

How has gene analysis led to the suggestion of three domains

Answer 19

Some organisms have parts of their genes that are not used in making proteins and other organisms that use entire genes to code for proteins, with no unused portions.

Question 20

How does selective breeding work

Answer 20

1- Parents with desired characteristics are bred
2- Offspring that inherited those characteristics are then bred
3- Process is completed until desired qualities are represented

Question 21

What are desired characteristics in plants (3)

Answer 21

● Large flowers
● Disease resistance in food crops
● Crops that produce high yields

Question 22

What are the negatives of selective breeding

Answer 22

● Reduced variation can cause species to be easily wiped out
● Inbreeding since there’s a reduction in the gene pool recessive genetic defects are likely to be expressed

Question 23

What is the process of tissue culture

Answer 23

1. Take a plant with desirable characteristics collect tissue sample from the roots and shoots
2. Using aseptic technique place tissue upon growth medium
3. Tiny samples develop into tiny plantlets
4. Plantlets are planted into compost

Question 24

What are the advantages of tissue culture (3)

Answer 24

● Produces lots of offspring with desirable feature
● Increases number of crops resistant to bad weather
● Can help endangered species

Question 25

What is some disadvantage of tissue culture (2)

Answer 25

● Takes a long time to adapt to the environment
● Tend to have a low survival rate due to genetic problems
● Gene pool is reduced

Question 26

What is genetic engineering

Answer 26

Modifying the genome of an organism to introduce desirable
characteristics

Question 27

What are the stages of genetic engineering

Answer 27

1. Restriction enzymes cut out genes
2. Same restriction enzymes are used to cut out a vector where genes are placed
3. Ligase enzyme attaches sticky end of gene and vector together
4. A recombinant gene id produced
5. Product is placed in species at early development so desired cells grow

Question 28

na

Answer 28

na

Question 29

What are the advantages of GM modification in animals

Answer 29

Gene therapy can be used to cure inherited disorders

Question 30

What is the use of tissue culture in plants

Answer 30

● Produce many identical plants
● To preserve species that are rare
● To produce plants that all have desirable traits e.g. tasty fruit, pesticide resistant

Question 31

What is tissue culture used for in animals (3)

Answer 31

● To grow tissues for transplant
● For research into tumour growth
● Research into viruses

Question 32

Give 3 advantages of GM of organisms that has benefitted people

Answer 32

● Production of crops with beta carotene - golden rice - needed for vitamin A - could improve deficiencies in developing countries
● Produce crops that have bt toxin gene that produces an insecticide
● Produce bacteria that proteins that help treat diseases - e.g. insulin

Question 33

What are the disadvantages to GM modification to produce GM organisms

Answer 33

Long term effects to biodiversity unknown as science isn’t fully developed

Question 34

What are Bt crops

Answer 34

Crops which are modified with a certain bacteria to that produce toxins to kill pests

Question 35

What are the positives of fertiliser

Answer 35

Provide useful nutrients like nitrates and phosphates making increasing yield and resistivity to environmental conditions

Question 36

What are the negatives of fertiliser

Answer 36

Can run off into rivers which kills wildlife and affects biodiversity

Question 37

What is biological control

Answer 37

The use of certain species to control the population of other species

Question 38

What are the advantages to biological control

Answer 38

Kills pests that potentially could damage crops

Question 39

What are the disadvantages to biological control

Answer 39

Reduces biodiversity and affects an ecosystems

Question 40

What are the 5 animal kingdoms

Answer 40

• animals (all multicellular animals)
• plants (all green plants)
• fungi (moulds, mushrooms, yeast)
• protists (amoeba, chlorella and plasmodium)
• prokaryotes (bacteria, blue-green algae)

Question 41

What is the order of Linnaeus order of classification

Answer 41

Kids prefer candy over fresh green salad
1. Kingdom
2. Phylum
3. Class
4. Order
5. Family
6. Genus
7. Species