Genetics Flashcards
(14 cards)
What is the structure of DNA?
Double helix, like a twisted ladder, the rungs are made up of hydrogen bonds and bases, the uprights are made up of alternating sugar and phosphate units.
What is genetic manipulation?
Also called genetic modification, is manipulating cells using biotechnology to change the genetic makeup.
- genetic info is changed by inserting new genes, which are then copied to daughter cells when parent cell divides (meiosis)
e.g. glow in the dark cat. Ethical issues could arise, health risks.
What is gene splicing?
Using enzymes scientists can cut bacterias enzymes open and splice (insert) desirable genes into the plasmid.
- The technology of combining DNA with different genes.
- Used to create insulin.
What is the process of gene splicing?
- Plasmid removed from bacteria.
- Plasmid is cut using enzyme.
- DNA is removed from human cell (donor DNA).
- DNA is cut using an enzyme to isolate a gene.
- Human gene is places into the plasmid to form recombinant DNA.
- The recombinant DNA is put back into bacterium.
- Bacteria cells grow and divide to produce any copies of the introduced gene.
What was Mendals experiment?
Carried out experiments on pea plants. in one experiment, he pure bred white flowers and red flowers which all produced the same genetic information. When he cross pollinated them together, the next generation was red. Mental called this the dominant characteristic., the other he called recessive.
Recall the number of chromosomes in a cell after meiosis compared to the original cell.
parent cell= 8 -> daughter cell= 4.
Therefore it has half the number of chromosomes.
Deduce when the sex of an individual is determined?
When the egg is fertilised by the sperm.
Meiosis is referred to as ‘reduction division’ because it produces daughter cells containing the haploid number of cells. Where would meiosis occur?
Production of gametes.
Where are chromosomes found?
In the nucleus of most cells in your body.
Most cells in your body contain 2 of each type of chromosome, recall the exception to this.
Gametes, as they have half the number of cells as the parent cell.
Compare and X and Y chromosome.
A Y chromosome is only carried by a male and is quite small, where as an x chromosome is much bigger and is carried y a female and a male.
Compare meiosis and mitosis.
Mitosis is the cell division that is responsible for growth and repair and contains the diploid number, Where as mitosis is the division that produce gametes which only contain the haploid number of chromosomes.
Compare genotype and phenotype.
The genotype is the genetic info that in unobservable where as the phenotype is the observable characteristic.
Compare heterozygous and homozygous.
Heterozygous is when there are two alleles on a homologous pair are different. A homozygous pair is when there are two are identical.
