Genetics Flashcards
what is a genome?
the entire genetic material of an organism, all the dna in an individual
what is a gene?
a gene is a short length of dna which codes for a particular characteristic or protein
what are chromosomes?
lengths of dna that occur as functional pairs in the nucleus
what is a nucleotide?
the building blocks of our dna, Each one is made up of a phosphate group, a pentose sugar and a base
describe the structure of dna
dna is made up of two nucleotide strands with a sigar and a phosphate backbone and interlinking bases to form a double helix
what shape is dna?
double helix
what are the base pairing rules?
adenine pairs with thymine (A-T)
guanine pairs with cytosine (G-C)
they are complementary to each other
what is it that makes us all unique?
the sequence of the bases along each chromosome is unique
what is a mutation?
a random change in the structure of dna, gene or chromosome
how does dna code for chromosomes?
along the dna, each sequence of 3 bases, called a base triplet, codes for one amino acid in the production of a protein
what is mitosis?
a type of cell division that produces daughter cells genetically identical to the parent cell and each other
what are clones of cells?
cells that are genetically identical to eachother
where does mitosis take place?
throughout the body
what is the purpose of mitosis? x3
- growth
- replacing worn out cells
- repair of damaged tissue
What is an allele
Different forms of the same gene
What is a genotype
Paired symbols showing the allele arrangement in an individual
Phenotype definition
The outward appearance of an individual
What is sex linkage
A gene that is carried on the sex chromosome
What is a test cross
A test crosses is used to determine the genotype of an organisms with the dominant phenotype
What is a genetic condition
A disorder caused by a fault within the genes or chromosomes
What is Huntington’s disease
Progressive brain deterioration, it is a dominant condition and becomes apparent in middle age. There is no cure
What is cystic fibrosis
It is when an individual has excess mucus production causing lung infections. It is recessive
What is haemophilia
People with it have a problem with blood clotting mechanisms. Caused by sex linked recessive allele in X chromosome
What is a plasmid
An extra loop of dna found in bacteria
Why are bacteria used in genetic engineering
Easily manipulated
Reproduce rapidly
Reproduce to produce identical offspring
Why is the same restriction enzyme used to cut out the gene and the plasmid
So that the sticky ends of the plasmid and gene have based on the sticky ends that complementary base pair with each other
What are the processes involved in downstreaming
Extraction
Purification
Packaging
Why are men most likely to inherit haemophilia
They only have to inherit one recessive allele, females have to inherit 2.
They only have one X chromosome and therefore doesn’t have a Y chromosome to mask the effect
What is an allele
Different forms of the same gene
What is a genotype
Paired symbols showing the allele arrangement in an individual
Phenotype definition
The outward appearance of an individual
What is sex linkage
A gene that is carried on the sex chromosome
What is a test cross
A test crosses is used to determine the genotype of an organisms with the dominant phenotype
What is a genetic condition
A disorder caused by a fault within the genes or chromosomes
What is Huntington’s disease
Progressive brain deterioration, it is a dominant condition and becomes apparent in middle age. There is no cure
What is cystic fibrosis
It is when an individual has excess mucus production causing lung infections. It is recessive
What is haemophilia
People with it have a problem with blood clotting mechanisms. Caused by sex linked recessive allele in X chromosome
What is a plasmid
An extra loop of dna found in bacteria
Why are bacteria used in genetic engineering
Easily manipulated
Reproduce rapidly
Reproduce to produce identical offspring
Why is the same restriction enzyme used to cut out the gene and the plasmid
So that the sticky ends of the plasmid and gene have based on the sticky ends that complementary base pair with each other
What are the processes involved in downstreaming
Extraction
Purification
Packaging
Why are men most likely to inherit haemophilia
They only have to inherit one recessive allele, females have to inherit 2.
They only have one X chromosome and therefore doesn’t have a Y chromosome to mask the effect
