GCSE Biology, 4.7- Variation and Evolution.

Rabbit X has thin fur.

Rabbit Y have thick fur.

Describe the process of natural selection if the environment is colder. [4 marks]

• Rabbit Y more likely to survive.

• They are more likely to reproduce.

• Their offspring could inherit the alleles for thicker fur.

• Their offspring is more likely to survive and reproduce.

Describe the process of selective breeding.

[4 marks]

• Select 2 parents that have desire characteristic.

• They reproduced sexually.

• Select the offspring that have desire characteristic.

• Breed offspring over many generation.

State 2 advantage of gentic engineering. [2 marks]

• Greater yield.

• Produce bigger or better fruits.

Describe the process of genetic engineering.

[4 marks]

• Use enzymes to isolate the require gene.

• Gene is inserted into a vector.

• Vector is used to insert the gene into the required cell.

• Genes is transferred into the cells of the targeted organism at an early stage.

Describe the process of taking cutting. [2 marks]

• Remove a small piece of plant you want to clone.

• Place cutting in rooting powder.

Describe the process of tissue culture. [2 marks]

• Divided the plant into group of cells.

• Cells are treated with hormone to help them grow.

Describe the process of embryo transplant. [4 marks]

• Collect sperm cell and egg cells from the animals with desired characteristics.

• Fertilisation and let fertilised egg to develop into an early stage embryo.

• Use glass rod to split embryo apart.

• Put embryos into the host mothers.

Sheep X and Sheep Y are different variation of sheep.

Sheep X is male.

Sheep Y is female.

Describe how can we clone sheep X by using adult cell cloning method. [5 marks]

• Collect the nucleus from an adult body cell of sheep X.

• Remove the nucleus from an unfertilised egg of sheep Y.

• Inserted the nucleus into an unfertilised egg.

• Give electric shock to the egg cell to form embryo.

• When embryo develop, then inserted into womb.

In 1859, a lot of people do not trust Charles Darwin’s theory of natural selection.

Suggest three reason why Charles Darwin’s theory is not accepted. [3 marks]

• Not enough proof.

• Its challenge the idea of god.

• Lack of understand of inheritance.

Describe the stage of speciation. [4 marks]

• Populations are separated.

• No longer can interbreeding between populations in different two place .

• Natural selection will happen on two different place.

• Over time, two different population are very different in their phenotype.

Describe how the work of Gregor Mendel led to our understanding of gene. [3 marks]

• He carried out breeding experiment on pea plants.

• Discover Inheritance of each characteristic is determined by units.

• It can passed to next generation which will be same unit.

Suggest why Mendel’s work may not recognised.

[1 mark]

Scientist don’t understand Mendel works.

What is meant by ‘fossil’. [2 marks]

Remains of organism from millions of years ago which found in rock.

Explain 3 ways that fossil can formed. [3 marks]

• Part of organism that not decay.

• Part of organism replace by minerals as they decay.

• Trace of organism.

Describe how could mutation of bacteria led to become antibiotic resistant. [4 marks]

• Mutation of pathogens produce new strains.

• There are chance of bacteria has antibiotic resistant during mutation.

• They survive and reproduce.

• Population of the resistant strain rises.

Suggest 3 ways that can reduce the rate of development of resistant bacteria. [3 marks]

• Patients should complete the full course of antibiotics.

• Restrict use of antibodies in farming.

• Do not give antibodies for virus infection.

This is half of the classification.

Fill the gap. [3 marks]

K________ → __________ → _________ etc

Put the answer like this:

X, Y, Z.

Kingdom, Phylum, Class.

This is the half of the classification.

Fill the gap. [4 marks]

Class → _____ → _____ → _____ → _____

Put the answer like this:

A, B, C, D.

Order, Family, Genus, Species.

Determine their binomial name. [2 marks]

Equus quagga.

What are the three domain system. [3 marks]

Archaea, bacteria, eukaryota.

What is meant by the following words in three domain system:

[3 marks]

a) Archaea.

b) Bacteria.

c) Eukaryota.

a) Primitive bacteria that live in extreme environment.

b) True bacteria.

c) Include protist, fungi, plants and animals.