genetics Flashcards
mendels law of segregation
•inherited characteristics are controlled by pairs of alleles that separate at gamete formation, with only one member of the pair of alleles being found in each gamete
mendels law of independent assortment
•when gametes are formed either of a pair of alleles is equally likely to combine with either of another pair of alleles
gene
•a piece of DNA that codes for a protein
recessive
•the allele is masked by the dominant allele
cause of gene mutations
•chemicals
•radiation
type of mutation and condition cause (other than gene)
•chromosome
•downs syndrome
what term is used to describe an allele present on the X chromosome
•sex linked
what does it mean that the genes aren’t linked
•the genes are present on different chromosomes
if genes were linked, in contrast to if they weren’t, what would happen
•less variation in offspring as linked genes tend to stay together during gamete formation
characteristics of mutant alleles in a population
•random occurrence
•low frequency
•disadvantageous
isolation
•removing a piece of dna from a cell
cutting
•dna is cut using restriction enzymes
gene expression
•production of protein
allele
•a version of a gene
incomplete dominance
•when both alleles are expressed
phenotype
•the physical expression of a gene
process of genetic engineering up to the point of expression
•isolation on DNA from cells
•cutting of gene from chromosome using restriction enzymes
•ligation of gene with vector or host DNA
•transformation of host cell, uptakes DNA
•cloning- production of identical copies of the bacterium containing target gene
•expression- formation of product
ligation
•the joining of two sections of DNA to form a single strand
transformation
•the uptake of DNA into the cell
cloning
•the production of identical copies of the bacterium containing the target gene
applications of genetic engineering in plants
•weed killer resistant crops
•many crops plants have bacterial genes added to them and are resistant to particular weed killers
•when herbicide is sprayed on the crop it’ll kill the weeds but not the transgenic plants
applications of genetic engineering in animals
•sheep produce a protein to treat emphysema
•some ppl have faulty gene so they can’t produce a protective protein in their lungs, leads to collapse of alveoli
•a working human gene for this protein has been inserted into sheep DNA and sheep can produce the protein in their milk
applications of genetic engineering in micro organisms
•bacteria make insulin
•involves inserting gene for human insulin into a bacterium then it produces large quantities of insulin
•means that ppl with diabetics could inject themselves with human insulin
species
•interbreeding/producing fertile offspring
role of RNA polymerase
•joins nucleotides together to make RNA
heterozygous
•the two alleles are different
genotype
•the genetic makeup of an organism
sex linked
•gene located on the x or y chromosome
