Genetics And Inheritance Flashcards
What is Heredity ?
Refers to the transmission of characteristics from parents to offspring.
What is Inheritance?
Refers to the set of characteristics that have been passed from parents to offspring.
What are Genetics?
Refers to the study of heredity and the variations that occur in the transmission of hereditary characteristics.
What is a Gene?
° A small part of DNA coding for a particular characteristic.
What is a Genome?
The Complete set of All the Genes in All the Chromosomes of a Particular Species.
What is a Phenotype?
The external appearance of an organism.
What is a Genotype?
The Genetic Composition of an Individual. (The genotype determines the phenotype)
What is Homozygous?
When an individual has two or more copies of the same allele for a particular characteristic.
What is Heterozygous?
When an individual has two contrasting or different alleles for a characteristic.
What does Monohybrid mean?
The reproduction between two individuals where we are concerned with the inheritance of only one characteristic or trait.
What does Dihybrid mean?
The reproduction between two individuals where we are concerned with the inheritance of two characteristics or traits.
What is Cross Fertilisation?
The Fusion of Male and Female Gametes.
What are the 3 Types of Dominace?
• Complete Dominace
• Incomplete Dominace
• Co-Dominace
What is Complete Dominace?
A Condition in which one allele of a gene is dominant over the other (recessive) such that only the dominant allele influences the phenotype in the heterozygous condition.
What is Incomplete Dominace?
No one allele of a gene is dominant over the other, a genotype consisting of these 2 alleles (heterogeneous) will therefore produce an intermediate phenotype that is different from the 2 homozygous conditions.
What is Co-Dominace?
A Condition in which two alleles of a gene have equal expression in the phenotype of an organism.
What is an Allele?
Two or More Alternative Forms of a Gene that arise by Mutation and are Found at the Same Place on a Chromosome.
What is a Locus?
The physical site or location of a specific gene on a chromosome.(plural: Loci)
Who is the ‘Father’ of Genetics?
° Mendel
What is a Mutation?
° A Mutation is any unexpected change in the genetic structure of a cell.
What is a Gene Mutation?
° Mutations that affect a single or a few base pairs in just a single gene.
Eg: Haemophilia, Colour Blindness and Albinism.
What is a Chromosomal Aberration?
° Changes in the normal structure or number of chromosomes.
Eg: Down Syndrome
What is Genetic Engineering?
° The Process whereby the genes on the DNA are changed, transferred or manipulated to produce a different organism.
What is Biotechnology?
° The use of Living things like cells, genes and biological systems, to create new products, technologies and medical treatments.
In what ways is Genetic Engineering an aspect of Biotech?
° Stem cell research
° Genetically modified organisms
° Clonning
What methods are used for Paternity Testing?
° Blood Grouping
° DNA Profiles
How are Genetic Links found?
° Mutations in Mitochondrial DNA used in tracing female ancestry.
Examples of Gene Mutations?
° Haemophilia
° Colour Blindness
Example of Chromosomal Mutation?
° Down Syndrome
Haemophilia
Absence of Blood-clotting factors
Colour Blindness
Due to absence of proteins that comprise either the red or green cones/ photoreceptors in the eye.
Down Syndrome
Due to an extra copy of chromosome 21 as a result of non-disjunction during meiosis.
True Breeing
Homozygous (The same, eg: TT and tt)
What is the position of a Gene on a chromosome?
° Locus
