1	Genetics & Heredity An overview of the history & principles of genetics
2	What is genetics? Genetics is the study of how organisms pass on information to their offspring It also explains characteristics & certain diseases.
3	What is a trait? A trait is a characteristic that is passed on from parent to offspring. Traits include eye color, hair color, metabolism, left or right hand. Acquired characteristics like strength & education are not passed on directly as traits.
4	Who discovered genetics? Gregor Mendel was a monk from Austria that is called the “Father of genetics”. He worked with pea plants. He studied several traits in the peas. He was able to predict outcomes & noticed patterns.
5	Mendel’s Findings He noticed that there were 2 versions of many traits. He noticed that in certain crosses 1 of the traits showed up more than the other. He called the trait that showed up more a dominant trait. The more hidden trait he called a recessive trait.
6	More of Mendel’s findings There are three possible gene combinations. 1. Homozygous (pure) dominant – 2 copies of the dominant gene. 2. Homozygous recessive – 2 copies of the recessive gene. 3. Heterozygous – 1 copy of the dominant gene & 1 copy of the recessive gene.
7	Punnett squares A Punnett square is a method used to predict possible gene combinations. Dominant genes are given capital letters. Recessive genes are given lower case letters. Ex Tall (T) is dominant over short (t) Possible combinations TT,Tt,tt.
8	How are traits passed on? Traits are passed from parents to offspring. They are passed by objects known as chromosomes. Genes are specific locations on chromosomes. Organisms receive 1 copy of each gene for a trait from each parent.
9	What is a pedigree? A pedigree is a diagram that shows the history of a trait in a family. They are good indicators that certain traits or diseases are possible. Males are squares. Females are circles. They are usually in order from youngest to oldest from left to right. Colored parts show the trait being looked at.
10	What is DNA? DNA stands for Deoxyribonucleic Acid It is a long thread – like material located in the nucleus of cells. It has a twisted ladder shape called a double helix. The shape was discovered by James Watson & Francis Crick.
11	The Genetic Code DNA is made of 4 nitrogen containing base. They are adenine,guanine,cytosine,& thiamine. The sequence of these bases in triplet pairs determine an individuals genetic code. Example: TAG could make left handed, TTG could make right handed.
12	Mutations Mutations are changes in the genetic structure. They can be DNA mutations or chromosome mutations. Mutations may be harmful, helpful or neither.
13	Gene Mutations
14	Chromosome Mutations
15	Genetic diseases SICKLE CELL ANEMIA TAY SACHS DISEASE CYSTIC FIBROSIS THALASSEMIA DUCHENNE MUSCULAR DYSTROPHY. PHENYLKETONURIA (PKU) MARFAN SYNDROME PROGERIA TRISOMY 21 OR DOWN SYNDROME SPINA BIFIDA ACHONDROPLASIA(DWARFISM) HUNTINGTON'S DISEASE FRAGILE X SYNDROME HEMOPHILIA KLINEFELTER SYNDROME TURNER SYNDROME TRISOMY 18 OR EDWARD SYNDROME CRI DU CHAT CLEFT LIP/CLEFT PALATE TRISOMY 13 OR PATAU SYNDROME Blue Rubber Bleb Nevus Syndrome Prader-Willi Syndrome Waardenburg Syndrome Retinoblastoma
16	Human Genetics Humans have 46 chromosomes (23 pairs) 1 pair is the sex chromosomes. Females have XX Males have XY
17	Genetic Counseling If couples have a history of genetic diseases they may wish to see a genetic counselor. They are specialized doctors who use pedigrees, Punnett squares & genetic screenings to determine probabilities of disorders. They then advise the couple of their findings & their options.
18	Genetic Engineering Genetic Engineering involves mapping the genes of organisms & manipulating them. Many of the ideas of genetic engineering are controversial because they involve controlling traits. Cloning, gene splicing, & gene therapy are part of genetic engineering.
19	Gene Splicing Gene splicing involves “cutting” an undesirable gene out of one organism & replacing it with a desirable gene from another. The organisms must be compatible. Examples: Frost & insect resistant plants & Beefalos. A Beefalo is an angus cow that has the size gene of the American Bison (Buffalo)
20	Cloning Cloning is the process of using DNA to produce a genetic duplicate of an organism. Not even identical twins are genetic duplicates. Sheep & cows have been cloned. Human cloning is illegal in the US.