Inheritance Flashcards
Genome
The entirety of an organism’s DNA
Genome’s function
Each gene within the genome codes for a particular sequence of amino acids. These sequences of amino acids form different types of proteins (enzymes, hormones, structural proteins like collagen)
How are chromosomes formed?
DNA double helix supercoils to form chromosomes
DNA Structure
double helix shape, complementary bases (Adenine pairs with Thymine and Guanine pairs with Cytosine), and sugar-phosphate backbone
RNA structure
- Uracil replaces Thymine
- Single strand
Protein synthesis
Process of turning a gene into a specific sequence of amino acids (that in turn makes up a specific protein)
Transcription
DNA is transcribed and an mRNA molecule is produced
Translation
mRNA is translated and an amino acid sequence is produced
Transcription role
Its role is to produce a copy of a section of DNA in the form of a strand of mRNA:
1. DNA double helix unwinds and unzips (hydrogen bonds break)
2. One strand acts as a template to make mRNA according to the complementary bases rule. e.g A-U, T-A, C-G, G-C
Translation role
Occurs in the cytoplasm and produces a chain of amino acids to form a protein:
1. mRNA molecule attaches to a ribosome
Alleles
Variations of the same gene
Phenotype
Observable characteristics such as eye colour and blood type
Genotype
The combination of alleles that control each characteristic
Dominant and recessive alleles
Dominant allele: Only needs to be inherited from on parent for the characteristic to show up on the phenotype
Recessive allele: Needs to be inherited from both parents for the characteristic to show up on the phenotype
Family Pedigrees
It helps work out the probability that someone in the family inherits a genetic disorder