Genetics Flashcards
Mono hybrid
Follow inheritance of one characteristic
Inheritance
Passing on characteristics from parents to children
Phenotype
Characteristics that result from genes and environment
Genotype
Genetic makeup of organism
Alleles
Different form of a gene
Diploid
2 sets of chromosomes
Gamete
Haploid, sex cell
Homozygous
Both alleles are the same
Heterozygous
Both alleles are different
Punnet square
Predict outcomes in a cross between two individuals
F1 gen
Children of parents
Dominant
Expressed in phenotype if present in genotype
Recessive
Only expressed in phenotype if dominant alleles not present
Test crosses
Suggest breeding experiment to find genotype
Use homozygous recessive, test cross
Codominance
Both alleles are expressed
Variation
Differences caused by genetics, environment or both
Evolution impact
Increase range in gene pool, increased chance of survival
Mutations
Random change in base sequence or chromosomal arrangement
Gamete mutations, passed on
Somatic mutation, not passed on
Not all harmful, some have no effect, amino acids have different sequences
Causes of mutation
Mutagens
Bacteria, viruses reproduce rapidly
Effects of mutation on population
Variation
Harmful, organism dies with mutation
Neutral or good, organism lives, passes it on
Natural selection
Organism competes for food Best suited survive Reproduce Pass on genes Repeat
Antibiotic resistance
Wrong reasons
Antibiotics kill good bacteria population
Resistant bacteria have less competition, reproduce
Antibiotic resistance
Not completing the full course
Kill bacteria causing illness
You feel better
Immune system wiped out bad bacteria
Less competition, resistant, reproduce
MRSA
Staph aureus resistant to methicillin
Reproduce
Pass on alleles
Become dominant
Selective breeding
Artificial selection of animals, plants Desired characteristics identified Bred Offspring with desired characteristics bred Repeated over many gens
Problems with selective breeding
Benefits humans, not animal
Reduce genetic diversity
Vector
Something which transfers gene, disease from 1 source to another
Plasmid
Plasmid
Small, circular piece of DNA in bacteria
Gene
Section of chromosome, creates a protein
Restriction endonuclease
Enzymes used to cut DNA in specific place
Ligase
Enzymes used to attach 2 pieces of DNA together
Recombinant organism
Genetically modified organism
Clone
Genetically identical cell, organism
Recombinant DNA
Altered DNA with more DNA added
Transgenic
Transfer of genetic material from 1 species to another
Genetic engineering of insulin
Insulin gene cut with restriction enzyme
Plasmid cut open with restriction enzyme
Insulin gene inserted into plasmid with ligase
Plasmid replaced in bacterium with ligase
Bacterium multiplies
Insulin gene switched on, insulin recovered from culture medium
Uses of GM bacteria
Human insulin Enzymes in biological washing powders Enzymes in food Human growth hormone Bovine somatotropin Human vaccines
Uses of GM plants
Resistant to herbicides
Tolerant to heat and drought and salt
Pesticide in plant leaves
Produce antibodies against illnesses
Uses of GM animals
Produce antibodies
Low cholesterol milk
Human antigens, transplant organs
Positives of GM foods
Feed world while keeping environmental destruction to minimum
Negatives of GM foods
Will not solve poverty, war
Enough food in the world, not distributed properly
Poor farmers use saved seeds, cannot afford gm seeds
GM seeds are sterile, need to be bought every year
Danger that genes are passed onto weedy relatives, super weeds
GM foods safe to eat?
Genes inserted are only DNA like genes, already there
New proteins introduced, never part of human diet, allergic reaction?
Cutting
Leaf, stem given right environment, genetically identical plant develops
Roots develop with hormone rooting powder
Quick, cheap
Lower transpiration, give roots time to form
Tissue culture
Exoplanets trimmed to size, transferred to plates with sterile nutrient agar jelly
Callouses
Different growth hormone, stimulate root, stem growth
Plantlets transferred to warm humid potting trays
Positives of tissue culture
Many plants in short amount of time Species that are hard to grow can be cultivated Produced at any time at year Large numbers can be stored easily Desirable characteristics
Disadvantages of tissue culture
Reduce gene pool
Reduced genetic variation
No chance of beneficial characteristics arising by chance
Cloning animals
Adult udder cell enucleated
Mature ovum from another organism enucleated
Nucleus and ovum body fuse with elec shock
Mitosis forming embryo
Cloned embryo implanted into uterus of 3rd organism
Lamb of sheep one, clone
