Processes

Question 1

Adult cell cloning

Answer 1

A nucleus is removed from an unfertilised egg cell
Nucleus from adult body cell inserted into egg cell
Small electric shock stimulates division to form embryo
Embryo contains same genetic info as adult
When embryo develops into a ball of cells, it is inserted into the uterus

Question 2

Selective breeding

Answer 2

Parents with specific desired traits are selected and bred together
Offspring with desired traits selected and bred
Desired alleles are passed down to offspring
Repeats over many generations until the whole population will have the characteristic selected for

Question 3

Different species

Answer 3

Populations of species are separated
Environmental conditions differ
Genetic variation in population caused by mutations
Natural selection means best adapted individuals will survive and reproduce
Pass alleles on
Over many generations, populations become so different that they will not be able to interbreed and form fertile offspring

Question 4

DNA structure

Answer 4

Genetic material in nucleus composed of chemical DNA
DNA is a polymer made up of 2 strands forming a double helix
DNA contained in chromosomes
Gene is a small section of DNA on a chromosome.
Gene codes for a specific sequence of amino acids to make a specific protein
Genome is the entire genetic material of an organism

Question 5

Protein synthesis

Answer 5

In the nucleus, a gene is copied onto a template molecule
Template moves into cytoplasm and attatches to ribosome
Messenger molecules bring amino acids to the growing protein chain in the correct order
When protein chain is complete, it folds to form a unique shape

Question 6

Fossils

Answer 6

Fossils are the remains of organisms millions of years ago
Formed because the conditions for decay are absent or when the hard parts (bones) are replaced by minerals when they decay
Can also be traces of organisms such as footprints, burrows and rootlet traces
Very few traces of soft-bodied organisms as they usually fully decay
Volcanic activity can also destroy fossils

Question 7

Human insulin from bacteria

Answer 7

Gene coding for human insulin taken from nucleus and cut using enzymes.
Plasmid taken from bacteria and cut with same enzymes
Plasmid placed back into bacteria cell
Bacteria cell divides rapidly by binary fission
Insulin harvested and purified

Question 8

How are gametes formed

Answer 8

Meiosis
DNA replicated
Cell divides twice, forming 4 cells which are all genetically different
Each cell has one set of chromosomes

Question 9

Tissue culture

Answer 9

Plant stem cut into many little bits
Placed in agar jelly
Agar contains glucose, auxin, nitrates, magnesium to stimulate support and growth
Plantlets develop, grow and are planted
Plant grows

Question 10

Evolution to become camoflauged

Answer 10

Variation in population due to mutations
Most camoflauged is most likely to survive
More likely to reproduce
More likely to pass on successful alleles
After many generations, camoflauged traits become more common

Question 11

Surrogate mother cows

Answer 11

Best mother and father cow sex cells are taken
Artificially fertilised
Forms an embryo
Embryo separated before differentiation
Many embryos placed into surrogate mothers to divide

Question 12

How could mutation cause enzyme to not work

Answer 12

Mutation changes bases in DNA
Active site is a different shape
No longer complimentary to substrate
Substrate can no longer bind to the enzyme
Enzyme does not function