Genetics And Genetic Engineering Flashcards
Genetics
A branch of biology that studies heredity and variation in organisms
Heredity
Passing on of traits/ characteristics from one generation to the next
Gene
A section of DNA (series of nucleotides/ bases) that controls a hereditary characteristic (trait), I.e. It is the basic unit of heredity in living organisms
Gene pool
All genes, or genetic information, in a population of sexually reproducing organisms
Hox genes
Master control genes that determine the way in which the body develops from a single zygote
Epigenetics
The control of genes
Genotype
Made up of all the genes an organism carries on its chromosomes which it has inherited from its parents
Phenotype
The physical appearance of an organism
Housekeeping genes
Genes active in many cell types which make proteins needed for basic functions
Homozygous
Pair of alleles at the locus are the same for a particular trait
Heterozygous (hybrid)
Pair of alleles a locus are different for particular trait
Monohybrid cross
Cross between parents with different alleles for a single gene
Generations
P1- parent generation
F1- first filial generation of offspring
F2- second filial generation of offspring
Pure breeding plants
Plants that always give rise to offspring that are similar to themselves
Complete dominance
A characteristic that is fully expressed in the phenotype of a heterozygous organism is the dominant allele
Mendel’s law of segregation
During meiosis, allele pairs separate (segregate) so that gametes have a single allele for each characteristic
Mendel’s law of dominance
In a cross of parents that are pure for contrasting traits, only the dominant trait will appear in the phenotype.
Recessive alleles will always be masked by dominant alleles
Mendel’s law of independent assortment
The alleles of different genes segregate randomly and independently of one another during gamete formation
Haemophilia
Rare, genetically determined condition of frequent, excessive bleeding as the blood clots very slowly
Polygenic inheritance
More than one pair of alleles responsible for a single trait
Continuous variation
Graduations of a characteristic in a phenotype (e.g. height in humans)
Mutation
Sudden change in the genetic make-up (DNA) of an organism
Mutagen
Factors that increase the rate of mutations, e.g. environmental factors such as ionizing radiation (UV/ X-Ray), mutagenic chemicals (benzene and carbon tetrachloride), viruses and micro-organisms
Neutral mutations
Do not affect life of the organism
Autosomal
Related to chromosomes that are not sec chromosomes
Albinism
Rare group of inherited genetic disorders that cause the skin, hair or iris of eyes to have little or no colour due to partial or complete absence of the pigment, melanin
Carrier
Has a recessive allele and a dominant alleles in each cell, therefore has a normal phenotype
SNP
(Single nucleotide polymorphism)
-biological markers
Genetic variations in a DNA sequence that occur when a single nucleotide is substituted for another nucleotide
Genome
Complete set of genetic instructions (genes) necessary to create an organism
HGP
-human genome project
International scientific research project set up in 1990
Genetic counseling
Health professionals with specialized graduate degrees and experience in the areas of medical genetics and counseling
Genetic engineering
Any direct manipulation of an organism’s genes
Biotechnology
Using scientific procedures to influence specific processes in living organisms which will benefit humans or improve the environment
Recombinant DNA
A form of DNA that does not exist naturally but is created by combining DNA sequences that would not normally occur together
GMO
Genetically modified organism
An organism with introduced foreign DNA that results in new and useful traits
Vectors
A virus (bacteriophage) or plasmid that transfers foreign genetic material into another cell
Plasmid
A circular, double stranded DNA molecule found in bacterial cells that are not part of the bacterial chromosome
Insulin
A hormone which lowers the glucose sugar levels in the blood
Restriction enzyme
Enzymes which cut DNA strands (which code for insulin) at specific sites to isolate the gene that codes for insulin
Ligase enzyme
Occurs naturally in the nuclei of cells and acts as ‘genetic glue’, joining together the ends of two single strands of DNA
Cloning
The process of artificially reproducing a gene, set of genes or a whole organism
Gene therapy
An experimental genetic engineering technique that replaces a faulty gene or adds a new gene in an attempt to cure disease or improve the body’s ability to fight disease
Transformation
The change in a cell or organism brought about by the uptake of introduced, foreign DNA
Transgenic organism
An organism that develops from a cell with recombinant DNA
Micropropagation
Method of producing plant clones by using plant tissue culture
Speciation
Hybridization between two species resulting in a new species
Cloning
The process used to create an exact genetic copy of another gene, cell, tissue or organism
Clone
Copied material which has the same genetic markup as the original
