Genetics-DNA and RNA Flashcards
Variation def. and causes
Differences in members of the same species
Causes: Sexual Reproduction and Mutations
Mutations def. and causes
Def: Change in the structure or amount of DNA.
Causes: Mutagens
Mutagen def. and examples
Def: An agent that causes mutations
Eg. Radiation (x-ray, UV rays) and chemicals (tobacco, many drugs)
Types of mutations
Gene
Chromosome
Gene mutation What Name Causes Symptoms Treatment
What: 1 gene change
Name: Sickle cell anaemia
Causes: RBCs are curved/sickle shape, insoluble haemoglobin, RBCs clump.
Symptoms: Paleness, Weak, Organ failure/damage
Treatment: Blood transfusions
Chromosome mutations What Name Causes Symptoms
What: Large change to several chromosomes
Name: Down Syndrome
Causes: 3 of pair 21 chromome
Symptoms: Physical and mental features
Evolution def.
Results in
Proven by
The way in which living things change genetically to produce different types of living things.
Results in New species being formed.
Proved by Charles Darwin
Work of Darwin
Developed the theory of natural selection and proved evolutuion
Outline of Natural Selection
- Organisms reproduce in large numbers
- Population of organisms will increase until environment can’t support it and they start to struggle to survive.
- Organisms show inherited variations to adapt and survive the environment. Therefore survival of the fittest.
Natural selection def.
The process by which organisms who have genetically controlled characteristics adapt to their environment for survival and reproduce to pass on these characteristics to next generation for survival.
Evidence of evolution
What
How it shows evolution
Fossils-remains of something that lived years ago. Shells, bones, teeth
They show the changes to modern organisms. Therefore they must have adapted genetically to produce varied organisms to survive and adapt to their environment.
Genetic Engineering
What
Artificial manipulation of Genes.
Involves removing a target gene (eg. gene for insulin production) from one organism and inserting it into another organism.
The other organism is then used to produce loads of target genes.
Steps of Genetic Engineering
- Isolate (target gene)
- Cut (gene at specific site)
- Insert (into the other organism)
- Transform (new organism)
- Express
Genetic Engineering
Isolate
DNA containing target gene is removed. Plasmid DNA from bacteria cell is removed with a genetic probe.
Genetic Engineering
Cut
DNA and Plasmid are cut at specific sites wth restrictive enzymes
Genetic Engineering
Insert
Target gene is inserted into plasmid. Called Ligation
Genetic Engineering
Transform
Plasmid (now transformed) is placed back into bacteria cell.
Genetic Engineering
Express
Bacteria cell is used to produce copies of target gene.
Applications of Genetic Engineering
- Micro-organisms, eg. bacteria used to make insulin to treat diabetes. (human gene inserted into bacteria)
- Gene for making of protective protein for human lungs-emphysema. (sheep)
- To make weed killer resistant plants-transgenic plants.
- Gene for blood clotting for haemophiliac sufferers. (sheep)
what is needed for genetic engineering
- Source of DNA
- Cloning vector (DNA to accept target DNA, eg. bacteria plasmid)
- Restriction enzymes to cut at restriction sites.
- DNA ligase: To glue or insert the target DNA into the cloning vector
Ethics of Genetic Engineering
Making genetically modified organisms (GMOs) can cause environmental damage, animals suffer, food sources being produced could be a concern
Other names for Genetic Engineering
Genetic alteration
Genetic Manipulation
Genetic Modification
Genetic Cloning