Topic 4 - Natural Selection And Genetic Modification - Definitios And Concepts

Question 1

Who is Alfred Russel Wallace?

Answer 1

A scientist that came up with the idea of natural selection, independently of Darwin

Wallace’s observations provided further evidence to support the theory of evolution, despite his proposed mechanism differing from Darwin’s.

Question 2

What are antibiotic-resistant bacteria?

Answer 2

Bacteria that mutate to become resistant to an antibiotic, survive and reproduce very rapidly

This rapid reproduction allows them to pass on their antibiotic resistance.

Question 3

What is Archaea?

Answer 3

One of the three domains consisting of primitive bacteria existing in extreme environments.

Question 4

What is Ardi?

Answer 4

A 4.4-million-year-old female hominid fossil showing phenotypic traits of both humans and apes.

Question 5

What is Bacillus thuringiensis (Bt)?

Answer 5

A soil-borne bacterium that secretes a toxin that kills insect larvae

The gene for toxin production in Bt can be introduced into the DNA of crop plants to provide insect resistance.

Question 6

What is Bacteria?

Answer 6

One of the three domains that consists of true bacteria.

Question 7

What is biological control?

Answer 7

The introduction of a new organism (often a predator) into an ecosystem to control a pest or pathogen.

Question 8

What is carbon-14 dating?

Answer 8

Estimating the age of carbon-containing material found in or alongside archeological remains.

Question 9

Who developed the theory of evolution by natural selection?

Answer 9

Charles Darwin.

Question 10

What is classification in biology?

Answer 10

The organisation of organisms into groups based on their characteristics and structure.

Question 11

What is competition in an ecosystem?

Answer 11

When different organisms compete for the same resources (e.g. light, water, mates, territory)

This limits population size and stimulates evolutionary change.

Question 12

What is Eukarya?

Answer 12

One of the three domains that consists of all eukaryotic organisms.

Question 13

What is evolution?

Answer 13

The gradual change in the inherited traits within a population over time due to natural selection.

Question 14

What are fertilisers?

Answer 14

Natural or artificial materials added to soils to provide essential nutrients and improve plant growth.

Question 15

What is the five kingdom classification system?

Answer 15

The classification of organisms into five major kingdoms: Animalia, Fungi, Plantae, Prokaryotae, and Protoctista.

Question 16

What are fossils?

Answer 16

The remains of dead organisms found in rocks which are millions of years old.

Question 17

What is a genetically modified (GM) organism?

Answer 17

An organism that has had its genome altered.

Question 18

What is genetic engineering?

Answer 18

The modification of the genome of an organism by the insertion of a desired gene from another organism.

Question 19

What is a genome?

Answer 19

The complete genetic material of an organism.

Question 20

What is ligase?

Answer 20

An enzyme that joins the sticky ends of the DNA and vector DNA forming recombinant DNA.

Question 21

Who is Lucy?

Answer 21

A 3.2 million year old female hominid fossil exhibiting more human-like phenotypic traits than ‘Ardi’.

Question 22

What is a mutation?

Answer 22

A random change in the base sequence of DNA which may result in genetic variants.

Question 23

What is natural selection?

Answer 23

The process by which the frequency of advantageous traits passed on in genes gradually increases in a population over time.

Question 24

What is a pentadactyl limb?

Answer 24

A limb with five digits present in animals, birds, reptiles, and amphibians.

Question 25

What is recombinant DNA?

Answer 25

A combination of DNA from two different organisms.

Question 26

What are restriction enzymes?

Answer 26

Enzymes that cut DNA molecules at specific sequences, creating sticky ends.

Question 27

Who is Richard Leakey?

Answer 27

A scientist that discovered many hominid fossils, including 'Turkana Boy'.

Question 28

What are selection pressures?

Answer 28

Environmental factors that drive evolution by natural selection and limit population size.

Question 29

What is selective breeding?

Answer 29

The process by which humans artificially select organisms with desirable characteristics.

Question 30

Fill in the blank: A limb with five digits present in animals is called a _______.

Answer 30

pentadactyl limb

Question 31

True or False: Natural selection leads to the gradual increase in frequency of advantageous traits.

Answer 31

True

Question 32

What are sticky ends?

Answer 32

The staggered cut formed by restriction enzymes in double-stranded DNA. ## Footnote Sticky ends facilitate the joining of DNA fragments during cloning procedures.

Question 33

What is stratigraphy?

Answer 33

Using the age of the layers of sediment surrounding archeological remains to estimate the age of the remains. ## Footnote This method is crucial in paleontology and archaeology for dating artifacts.

Question 34

Define taxonomy.

Answer 34

The classification of organisms into taxa: kingdom, phylum, class, order, family, genus, species. ## Footnote Taxonomy helps in understanding the relationships and characteristics of different organisms.

Question 35

What is the three-domain system?

Answer 35

A method of classification in which organisms are categorised into three groups: Archaea, Bacteria, and Eukarya. Developed by Carl Woese. ## Footnote This system reflects the evolutionary relationships among these groups.

Question 36

What is tissue culture?

Answer 36

A method of growing living tissue or cells in a suitable medium to produce clone plants. ## Footnote Tissue culture is widely used in plant breeding and genetic engineering.

Question 37

What is a vector in genetic engineering?

Answer 37

A carrier used to transfer a gene from one organism to another. ## Footnote Vectors can be plasmids, viruses, or artificial chromosomes.