CATALYST Catalyst: Complete a dihybrid cross for a Heterozygous Tall person and a Homozygous Short Person. T = Tall, t = Short Catalyst: Complete a dihybrid cross for a Heterozygous Tall person and a Homozygous Short Person. T = Tall, t = Short Mr. Gibney will start this on board promptly when bell rings Mr. Gibney will start this on board promptly when bell rings CURRENT EVENT BY FRIDAY!!!! CURRENT EVENT BY FRIDAY!!!!
HOMEWORK REVIEW CURRENT EVENTS (I will give you till Wednesday) -HELP US See Science in everyday life
“Very nice résumé. Leave a sample of your DNA with my secretary.”
Gibney Bucks Review!!! How do mitosis and meiosis differ? How are people either male or female? What is DNA? What is replication? What is transcription? What is translation? When is Reading day this week? STUDY ROCK THIS CLASS YOU CAN BRING YOUR GRADE UP IF YOU TRY!
Think for a second about the most crazy thing you have ever seen…
when something like THIS could be possible… Imagine in the future…
The future is now…
WELCOME TO GENETICS!!!
Follow Along In Book Ch 10 Fill in guided notes as we go along and if you miss something… check out the book!
WHY THIS IS IMPORTANT!!!!!!
GENETICS the study of how traits are passed from one generation to the next
TRAIT a characteristic Examples: Plant size, seed color, pod shape
TRAITS YOU MIGHT HAVE…
Can you curl your tongue? Can you wiggle your ears? Can you raise just one eyebrow? USA: 82% Yes USA: 27% Yes USA: 64% Yes
GENES Each feature of the pea plants is controlled by a gene. It may have a gene that controls its color, another for size and another for shape.
GENE the factors that control traits (found in the DNA)
Above you see chromosomes. The circled area is a gene on chromosome #22. The absence of this gene causes velo-cardio- facial syndrome (VCFS) which may cause ADD and mental illness
ALLELES Each gene comes in different forms called alleles, so the gene that controls flower color may come in two alleles: purple and white.
ALLELES different forms of a gene
PURPLE MAN EATER PLANT EXAMPLE Traits: 6ft tall, purple, eats people Genes that control these traits are on Chromosome 17 Each of the three genes has different alleles: Can be 6ft tall or 3 ft tall, purple or orange, eat people or vegetarian
GREGOR MENDEL The “father” of genetics Lived from Austrian Monk Published his work in 1866, but no one took him seriously until Studied Pea Plants!
MENDEL’S EXPERIMENTS
Mendel experimented with 7 different characteristics
Mendel Got Lucky for 2 Big Reasons 1. First, he had a lot of time…he was a monk. This let him do LOTS of experiments with the peas! 2. Each trait had 2 options. This was key because he could tell if it was one way or the other.
VOCABULARY "Think! How the hell are you gonna think and hit at the same time?"
HOMOZYGOUS organism with two identical alleles for the same trait (TT or tt)
HETEROZYGOUS organism with two different alleles for the same trait (Tt)
DOMINANT allele that is expressed when in the presence of a recessive allele (TT or Tt = tall)
RECESSIVE allele that is expressed only when homozygous (tt = short)
PHENOTYPE physical characteristics (Tall, Brown)
GENOTYPE the genetic makeup (TT, TtHh)
GENE = Height ALLELE = Tall, Short Gene is represented by the letter “t” Dominant = T Recessive = t Remember you need 2 copies of every gene!!!
How can we determine what the offspring are going to be?
PUNNETT SQUARES
Reginald C. Punnett Inventor of the Punnett Square
PUNNETT SQUARES chart showing the possible combination of alleles in a cross
Punnett Squares show the probability of getting a certain type of offspring
THE PARENTS GENOTYPES DAD = Tt (heterozygous) MOM = Tt (heterozygous) PHENOTYPES DAD = Tall MOM = Tall
PUNNETT SQUARES
THE OFFSPRING TT (homozygous dominant) Tt (heterozygous) tt (homozygous recessive) GENOTYPES 1TT:2Tt:1tt (1:2:1)
THE OFFSPRING TT (tall) Tt (tall) tt (short) PHENOTYPES 3 Tall :1 Short (3:1)
STUDENT DEMOS UP FRONT Do student demonstration with genotypes Do bag demonstration with beans tomorrow
Cross a homozygous dominant with a recessive (for height where T is dominant and tall). Find the genotype and the phenotype
Cross a heterozygote with a recessive (for height where T is dominant and tall). Find the genotype and the phenotype
Cross a heterozygote with another heterozygote (for skin color where Black is B, b = white). Find the genotype and the phenotype
Cross a heterozygote with another heterozygote (for nose size where big nose is N and small nose is n). Find the genotype and the phenotype
When you flip a quarter, what are the odds that a coin turns up heads? What about when you flip two coins at the same time, what are the odds that both turns up heads? Coin Flip Lab Coin 1 Coin 2 HeadsTailsHeadsTails % Heads% Tails% Heads% Tails
A cross between an unknown and a homozygous recessive Test Cross
Example of a Test Cross Unknown
When a combination of the dominant and recessive creates a new phenotype. RR = red, rr = white, and Rr = pink Codominance
RRRrrr
Codominance Cross
a trait that is found on either the X or Y chromosome Sex Linked Trait
Hemophilia is an example of a sex linked trait.
a disease where your blood doesn’t clot. Hemophilia
Hemophilia only occurs when all of the X chromosomes have a copy of the recessive gene.
X H X h : female carrier X h X h : female hemophiliac X H Y: normal male X h Y: hemophiliac male
SICKLE CELL ANEMIA
Difference between normal cells & sickle cells
Sickle Cell ss = sickle cells (lethal) Ss = carrier (SC trait) SS = normal
Sickle Cells tend to get stuck easily in the circulatory system.
Why would African American’s be so much more likely to have Sickle Cell?
Regular red blood cells infected by malaria
chart that shows the relationships within a family PEDIGREE
Pedigree Basics Males are squares, females are circles, and unborn babies are triangles or octagons Shaded figures represent individuals with the trait, a carrier could be 1/2 shaded Generations are numbered with roman numerals (I, II, II, IV) from top to bottom People within generations are numbered (1,2,3) from left to right
PEDIGREE HELP!!!!
200 B.C. Humans “clone” trees by cuttings
1950 Humans clone frogs
1980’s Humans clone mice!
1997 HUMANS CLONE SHEEP!!!
1998 Humans clone 8 copies of a cow!!!
20??
moving genes from one chromosome of one organism to the chromosome of another GENETIC ENGINEERING
“Fat” Gene
making an exact copy of another cell / organism CLONING
Dolly—the first cloned sheep Ian Wilmut, the dude that did it
Check out this short movie that talks about cloning…
A dividing cell
Read NYTimes Article "Despite Warnings, 3 Vow to Go Ahead on Human Cloning" a. What did three proponents of human cloning announce on August 7, 2001? b. Where did they make this announcement? c. Why did some scientists at the symposium object to the proponents' announcement? d. Why did Dr. Alan Colman object to the research by these proponents being done in secret? e. According to the article, what was the consensus among the panel and most of those who testified before it?
Read NYTimes Article "Despite Warnings, 3 Vow to Go Ahead on Human Cloning" f. Who was "Dolly"? g. What animals have been successfully cloned? h. According to the article, what is involved in cloning a human? i. How did the three proponents say they would address the possibility of genetic abnormalities? j. How did other experts at the symposium respond to this statement? k. Why do the proponents need to conduct their research secretly?
yping/karyotyping.html y/cytogallery.html omaldisorders.html
A technique used to determine the genetic traits of a baby before it is born AMNIOCENTESIS
Klinefelter Syndrome Have male genitalia and internal ducts, but underdeveloped testes Do not produce sperm Slight enlargement of the breasts 47,XXY 1 out of every 500 male births
Turner Syndrome Has female external genitalia Underdeveloped ovaries Short (under 5 feed) Webbed Neck Broad, Shield-like chest 45,X 1 out of every 3000 female births
Cri-du-Chat Syndrome Partial monosomy (part of 1 chromosome is lost) Loss of about 1/3 of the short arm of chromosome 5 Anatomical malfomrations (gastrointestinal and cardiac complications) Mentally retarded Abnormal development of the larynx which makes the baby’s cry sound like a cat’s cry 1 in 50,000 live births
Down Syndrome BKA trisomy 21 (47, 21+); 3 copies of the 21 st chromosome Short Small round heads Protruding, furrowed tongues which cause mouth to remain partially open Retarded (IQ below 70) Shortened life expectancy (<50) Prone to reparatory disease and heart malformations Have 15x higher chance of getting leukemia Chance of having a baby with Down syndrome goes up as the mother gets older
Guided Notes Mini-Clinical: 10pts I meant to start these backup again but got caught up in the excitement of getting a room. On a clean sheet of paper answer the following… you may use your notes
1. How do the base pairs in DNA matchup? 2. What is the difference between DNA and RNA? 3. How do transcription and translation differ? 4. Name 2 scientists that we talked about who helped “discover” DNA 5. Draw the pathway from DNA to protein.
TRADE N GRADE How do the base pairs in DNA matchup? A-T, G-C
Pedigree Basics Males are squares, females are circles, and unborn babies are triangles or octagons Shaded figures represent individuals with the trait, a carrier could be 1/2 shaded Generations are numbered with roman numerals (I, II, II, IV) from top to bottom People within generations are numbered (1,2,3) from left to right