B2.4 Applied Genetics Flashcards
Where is genetic info stored?
Chromosones in the nucleus
Chromosones appear in pairs in most cells, list the 2 that they don’t appear in cells.
Gametes and bacterial cells
What repeating unit is DNA made from?
A repeating unit called a nucleotide
What is the shape that makes up DNA called?
Double Helix
What does A join?
T
What does C join?
G
What is the name given to the code that is a sequence of 3 bases which make up an amino acid?
The triplet code
List 3 things cell division allows organisms to do
Grow
Repair
Replace worn out cells
What process is it when a parent diploid cell produces two identical daughter cells?
Mitosis
What is the process called when two haploid daughter cells divide to produce 4 other cells?
Meiosis
Explain the independent assortment of chromosomes.
The way chromosones arrange themselves before the cell produces genetic variation in gametes
What can genetic screening predict before pregnancy?
The likely hood of a child having a genetic condition
What can genetic screening determine during pregnancy?
If a child has a genetic condition
List 4 groups of people who should be offered genetic screening
Older mothers
People who have a family history of genetic conditions
Mothers who have a genetic abnormality in previous pregnancies
Those identified as at risk from previous scans
What is genetic engineering?
The process that modifies a genome to introduce a desirable trait
Define genetic engineering
The process of modifying genomes in an organism to introduce a desired trait
Explain how human insulin is produced
Insulin gene cut from human chromosome with a restrictive enzyme - leaves ‘sticky ends’
Plasmid removed from bacterial cell using same enzyme leaving sticky ends
Gene is fitted into plasmid and returned to bacterial cell
Bacteria multiply (mitosis) to produce insulin
List 4 advantages of production of human insulin
Unlimited supply
More ethical
More efficient (using actual human insulin)
No risk of transmission of infection
What do genes control? What do genes code for?
Controls characteristics
Codes for a protein
What is an allele a different form of?
Different forms of the same gene
What are weaker alleles known as being?
Recessive
What are stronger alleles known as being?
Dominant
What does the term heterozygous mean?
When two alleles are different
What does the term heterozygous mean?
When two alleles are different
What does a phenotype show?
The outcome of the genotype
How do you identify the unknown genotype of a parent?
Cross it with a homozygous recessive partner
What two chromosomes do females have ?
Two X chromosones
What two chromosomes do males have?
One X and one Y
What type of condition is Haemophila?
A sex linked condition
What is haemophila caused by?
A reccessive allele in males - females can be carriers but not have the condition
What is cystic fibrosis caused by?
Recessive allele
What is Huntingtons caused by?
A dominant allele
What is down syndrome caused by?
An extra copy of chromosome 21
What test is carried out to determine if a child will have down syndrome?
Amniocentesis
What is a risk associated with an amniocentesis test?
Chance of miscarriage
How many chromosomes total would a person with down syndrome have?
47
What is an allele that will only show in the phenotype if both of that allele are present?
A recessive allele
Name one cell where mitosis occurs
Lungs
Name one cell where meiosis occurs
Testicles
What does the term haploid mean?
When a cell or organism has half the number of chromosomes
What does the term diploid mean?
When a cell or organism has it’s full number of chromosomes
How many cell divisions does Mitosis have?
1
How many cells does mitosis produce?
2
List, in order, the 3 stages of the downstreaming process in the production of human insulin.
Extraction
Purification
Packaging
In the structure of DNA, what compound is in the shape of a pentagon?
Sugar
In the structure of DNA, what compound is in the shape of a circle?
Phosphate
In the structure of DNA, what compound is attached to the pentagon which is not a circle?
Base
What is each base triplet a code for?
Amino Acid
What is information contained in the gene known as?
The genotype
How is a person’s genotype represented?
Two letters
