B3.1 - New Technology Flashcards
How many genes are there for one characteristic?
There are two genes for the same characteristic, one inherited from the mother and one from the father.
What is meant by an allele?
An allele is a different form of the same pair of genes.
What is the difference between the dominant and recessive alleles?
Dominant alleles are always expressed in the organism while recessive alleles are only expressed when two copies are present.
This means that only one copy of the dominant allele needs to be present for the characteristic to be shown in the organism. Two recessive alleles are needed for the characteristic to be shown in the organism.
What is a Punnett square?
A Punnett square is a table which shows what happens to alleles in a genetic cross.
img: https://useruploads.socratic.org/V0oiMzSfRaCrAfg9V5wN_punnett.jpg
If the fathers alleles are ‘Bb’ and the mothers alleles are ‘bb’, what is the chance (%) that the offspring inherits the recessive characteristic?
B b
b Bb bb
b Bb bb
The chance that the offspring inherits the recessive characteristic is 50%.
This is because the recessive allele is always shown as the uncapitalized letter and that there has to be 2 copies present (‘bb’) of the recessive allele to be expressed.
What are genetic disorders?
Genetic disorders are anomalies in genes.
what is meant by a carrier of a genetic disorder?
A carrier means the person has one allele of the disorder but does not have the disorder.
If a genetic disorder is caused by a recessive allele ‘c’ then a carrier can have one recessive allele and one dominant allele but still not have the disorder. This person is a carrier.
What is meant by selective breeding?
Selective breeding, or artificial selection, is breeding specific organisms to gain specific characteristics.
What is an advantage of selective breeding?
Certain desirable characteristics can be gained in an offspring that could help a farmer.
What is a disadvantage of selective breeding?
Selective breeding can cause loss of variation within a species because every generation organisms will have more and more similar genes.
What is genetic engineering?
Genetic engineering is altering an organism’s genes to produce an organism with desirable characteristics.
Name an advantage of genetic engineering?
It is a very quick way to produce an organism with desirable characteristics compared to selective breeding.
Name a disadvantage of genetic engineering?
The release of genetically modified organisms into nature can cause spread of diseases and decrease animal welfare.
How does one organism gain a desirable characteristic through genetic engineering?
Genes from another organism (foreign genes) are taken that show the desirable characteristic and are placed into the organism that scientists want genetically modified.
What are two useful chemicals that can be produced by genetically modifying bacteria?
Vaccines and antibodies.
What is the name for the genetic disorder where a person is born with an extra finger/toe?
Polydactyly
Is polydactyly caused by the dominant or recessive allele?
Dominant
What is cystic fibrosis (CF)?
It is a genetic condition that causes sticky mucus to build up in the lungs and the pancreas.
Is cystic fibrosis caused by the dominant or recessive allele?
Recessive
What is homozygous?
Homozygous - having two identical alleles
What is heterozygous?
Heterozygous - having two opposite alleles
What is respiration?
Respiration is a transfer of energy.
What is the word equation for aerobic respiration?
oxygen + glucose → carbon dioxide + water
What is the word equation for anaerobic respiration?
glucose → lactic acid
Name two examples where yeast is used.
production of bread and alcohol
Fermentation is a type of anaerobic respiration, what is the word equation for it?
glucose → carbon dioxide + ethanol
Fermentation is used by the microorganism yeast.
What does pasteurised mean?
Pasteurised - heated to high temperatures to kill harmful bacteria
It is used in making yoghurt
What is cloning?
Cloning is producing an identical copy of an organism. This means it has the exact same genetic code like the parent.
Name one medicine that is produced by bacteria cloning.
Insulin
What is asexual reproduction
Asexual reproduction is reproduction but without a partner.
What is biotechnology?
Biotechnology is the use of biological processes to create useful products.
When making bread, fermentation is used by yeast. Why is there no ethanol in the dough after it it is baked?
The ethanol evaporates in the oven.
What is the product when lactose is fermented?
Lactic acid
What is ‘live’ yoghurt?
Live yoghurt is yoghurt that is not pasteurised after it has been made.
What are enzymes?
they are catalysts - they speed up reactions without being used up
What is a denatured enzyme?
Denatured means an enzyme that can no longer catalyse a reaction. This is caused when an enzyme is in a temperature that is too high for it. When an enzyme is denatured it loses its shape.
What does insulin do?
Insulin helps regulate (control) your sugar levels by breaking down glucose.
What disease do you get if you don’t produce enough insulin
Diabetes
