1. Genetic Changes
Life Science
Chapter 8

2. Mutations Mutation – any change in an organism’s genetic material
Almost always harmful.
Usually occurs randomly.
Single base pair exchange for another
Can involve a whole chromosome, or set of chromosomes.
Lethal mutation – a mutation that causes death

3. Gene Mutation
Gene Mutation – a change in the sequence of bases in a gene; directly affects the protein formation
Some mutations have more of an effect than others
Eye-color gene mutates in a finger cell, probably no affect.
Skin cell affecting color – might produce spot in skin
Skin cell with lethal gene mutation

4. Gene Mutations
Somatic mutations – occur in cells that do not make gametes (body cells)
Not passed on to future generations
Germ mutations – occur in gametes or cells that form gametes
May not affect organism but can be passed on to the offspring and affect them
Mostly recessive

5. Chromosomal Mutations
Chromosomal Mutation – involves the number of chromosomes or the number of genes or location of genes on a chromosome
Does not directly affect the protein formation
May cause an organism to have some different traits
Down’s syndrome – three 21st chromosomes

6. Human Mutation Disorders
Hemophilia
Known as “bleeders disease”
Sex-linked, more prominent in males, females can be carriers
Missing blood clotting chemical

7. Human Mutation Disorders
Duchenne Muscular Dystrophy
Sex-linked
Muscle deterioration
Muscles enlarge and swell, then shrink and waste away

8. Human Mutation Disorders
Cystic Fibrosis
Recessive trait disorder
Thick mucous that blocks glands and pores; causes thick, sticky mucus.
Severely affects the lungs, usually cause of death

9. Human Mutation Disorders
Tay-Sachs
Lack enzyme that breaks down fatty substances.
Fatty substances build up in nervous system and cause death of neurons; blindness, seizures, paralysis, finally death usually by age 5.

10. Human Mutation Disorders
Malignant Hyperthermia
Dominant gene mutation
Mostly discovered when someone has general anesthesia (are put to sleep for surgery)
Triggers sudden high blood pressure and extremely high body temperature

11. Human Mutation Disorders
Achondroplasia
Dominant gene mutation
Causes long bones in arms and legs to stop growing prematurely
Normal size head and body with short arms and legs
Most dwarfs have this.

12. Applied Genetics
Selective Breeding – man chooses organisms with desirable traits and breeds them with the hope that the offspring will carry the desired traits
Inbreeding – mating of an organism with it’s close relative
Ex. Pink roses, short-legged sheep, Labradoodles

13. Applied Genetics
Crossbreeding (hybridization) – breeding individual traits from different varieties to produce offspring that have the traits of both parents
Ex. Breeding wheat that resists certain fungal diseases, with a wheat that survives cold temperature. Offspring, called Marquis wheat, has both traits.
Genetic Engineering – the use special techniques to control the genetic makeup of an organism

14. Clones
Clone- group of genetically identical organisms that were produced by sexual reproduction.
Cloning- ethical dilemmas

15. Twins Identical – result of a single sperm and ovum uniting.
Technically clones
Fraternal- result of two sperm and two ovum uniting separately.
Not the same genetic makeup.

16. Human Genetic Engineering
Man is made in God’s image
We have the God-given ability to learn, gain knowledge, and direct our lives.
We must use knowledge wisely.