Entrance Activity: Daily Objective: Tuesday, March 17th , 2015 _______________________________________________ Entrance Activity: Daily Objective: Open your book to page 307 and read through the chapter mystery. By the end of today I should be able to… Explain the difference between a gene and a trait Do the best you can to give an answer to Susan’s questions: Identify homologous chromosomes Why aren’t any of the chicks green? What happened to the green color of the bird’s parents?

Gregor Mendel Who: An Austrian monk in the 1800s Why he’s important: He developed an explanation for the mechanism of evolution

What Mendel did… F2 Generation P Parental F1 Generation

Mendel’s Conclusions Inheritance is determined by factors that are passed from one generation to the next, genes. The principle of dominance states that some alleles are dominant and others are recessive.

REVIEW Mendel Traits Alleles Genes

Traits: A specific characteristic Mendel used the following characteristics in his pea plant studies Seed shape: round or wrinkled Seed color: yellow or green Pod shape: smooth or constricted Pod color: yellow or green Flower position: axial or terminal Plant height: tall or short

Daily Objective: BTEOTISBAT… Wednesday, March 18th, 2015 Daily Objective: BTEOTISBAT… Describe how dominant and recessive traits interact Describe the genotype and phenotype of an individual Entrance Activity: Grab a vocab flipper from the first counter fold it in half with the words on the outside. Use your book to fill in the first 3 words please…

Genes and Alleles Gene = unit of heredity (flower color) Alleles = different forms of the same gene. Example: the gene for flower color may be a red allele (R) or a white allele (r)

Genetic Traits Types of allele: Dominant = allele that hides another allele. As long as there is one dominant allele, it will be expressed (show up) in an organism. Recessive = allele that is hidden. It can be masked by a dominant allele. It will show up if no dominant allele is present

Chromosomes Humans have 23 PAIRS of chromosomes

Homologous pairs… Two chromosomes with the same genes but can have different forms… Example the first Pair has your eye color Gene on it, the left Comes from your mom The right comes from Your dad…

Now Mendel created hybrid plants who expressed the traits of only one parent. One plant’s Allele for a trait had been dominant, while the other parent plant’s had been recessive. So what happens to the recessive alleles for a trait?

How did this separation, or segregation, of alleles occur? Mendel suggested that the alleles for tallness and shortness in the F1 plants must have segregated from each other during the formation of the sex cells, or gametes.

Mendel’s Laws LAW OF SEGREGATION = one allele from each gene pair goes into each sex cell.

YOU MUST KNOW THIS PART Homozygous: the homologous pair is made of 2 of the same type of alleles Heterozygous: the homologous pair is made of 2 of different type of alleles

Phenotype = what they look like Genotype = what alleles they have Ex. Tt Phenotype = Tall Genotype = Tt *Some alleles are neither dominant nor recessive, and many traits are controlled by multiple alleles or multiple genes

GENOTYPE In Mendel’s experiments, there were two alleles for each trait, one from each parent. Height could either be short or tall Lets use “T” to represent tall alleles and “t” to represent short alleles Homozygous – an organisms has two identical alleles, like “TT.” Both parents gave a tall allele (Dominant or recessive) This can also be called a Purebred Heterozygous – an organisms has two different alleles, like “Tt.” Parents gave different forms of the height gene This can also be called a Hybrid

By the end of today I should be able to… Thursday, March 19th, 2015 ENTRANCE TASK _______________________________________________ In guinea Pigs, having a Black coat (B) is dominant to having a white coat (b) Daily Objective: By the end of today I should be able to… Use a Punnett Square to predict the outcome of a specific Genetic Cross What genotypes could a Guinea Pig with a black coat have? What genotype does a guinea pig with a white coat have?

Daily Objective: Same as yesterday ENTRANCE TASK Friday, March 20th, 2015 _______________________________________________ In purple-people-eaters, one-horn is dominant and no horns is recessive. Draw a Punnett Square showing the Daily Objective: Same as yesterday ENTRANCE TASK cross of a purple people eater that is Heterozygous for horns with a purple people eater that does not have horns. Using the back of yesterday’s sheet, complete the following genetic cross: Summarize the genotypes & phenotypes of the possible offspring

HW: Draw Figure 11-5 on page 312 in your notebook

Genetics and Probability Probability is the likelihood that something will occur. Probability is used in genetics to predict the outcome of genetic crosses Flip a coin…What is the probability that you will get heads? What is the probability that you will get heads 3 times in a row?

PunnetT Squares Punnett squares use mathematical probability to help predict the genotype and phenotype combinations in genetic crosses… Page 316

Punnett Squares 1. Start with the parents

Punnett Squares We will cross two homozygous parents TT – homozygous dominant tt – homozygous recessive

Practice makes perfect

In Humans, tall (E) is dominant over short (e) In Humans, tall (E) is dominant over short (e). What are the genotypic and phenotypic ratios of potential offspring between 2 individuals who are homozygous dominant and heterozygous? Parent Genotypes? _________ X __________

Homologous chromosomes separate and two new cells are formed

Meiosis II Each daughter cell has ONE Allele of each gene instead of two… that is what makes them sex cells

Homework… Using your offspring’s phenotype, you will create a picture of your offspring. It needs to include all characteristics

By the end of today I should be able to… Monday, March 23rd , 2015 One cat carries heterozygous, long-haired traits (Ss), and its mate carries homozygous short-haired traits (ss). Use a Punnett square to determine the probability of one of their offspring having long hair. _______________________________________________ Daily Objective: By the end of today I should be able to… Describe the inheritance patterns that exist beyond simple dominance

Incomplete Dominance = The heterozygous phenotype is somewhere in between the two homozygous phenotypes

WW RR RW

Co-dominance = Both traits will show up Co-dominance = Both traits will show up. They are not blended together, you actually see both

Test your knowledge… With a partner, decide whether the following picture is an example of incomplete dominance or codominance… What would the genotype of this flower be?

By the end of today I should be able to… Tuesday, March 24th, 2015 ENTRANCE TASK: _______________________________________________ Is the flower in the picture showing incomplete dominance or codominance? How do you know? Daily Objective: By the end of today I should be able to… Describe the inheritance patterns that exist beyond simple dominance What would its genotype be?

Multiple Alleles Keep in mind, an individual can only have two alleles for a particular gene BUT more than two possible alleles can exist within a population Example: Blood Type Look at figure 11-12 on page 273

Polygenic traits Traits that are controlled by two or more genes are called polygenic traits Eye Color Skin Color

Independent assortment Pg. 271 Genes for different traits can segregate independently during the formation of gametes (sex cells) Example: The seed shape and seed color genes do not influence each other’s inheritance.

By the end of today I should be able to… Complete a dihybrid cross\ Thursday, March 25th, 2015 Read through page 316 _______________________________________________ Daily Objective: What is the difference between a one factor and a two factor cross? By the end of today I should be able to… Complete a dihybrid cross\ ENTRANCE TASK Have out all 4 of your homework assignments. In guinea Pigs, having a

Review of Monohybrid Crosses Remember, monohybrid crosses involve only ONE trait Practice… In fruit flies, red eyes are dominant over white eyes. Cross a white-eyed fly with a homozygous dominant red-eyed fly. Cross two heterozygous red-eyed flies. Draw a Punnett square for each cross, and determine the genotypic and phenotypic ratios.

Review of Monohybrid Crosses Can you determine the genotype of a white-eyed fly just by looking at it? Yes- it’s rr of a red-eyed fly just by looking at it? No- it could be RR or Rr How could you determine the genotype of the red-eyed fly? Perform a test cross

Dihybrid Cross: a cross that shows the possible offspring for two traits Coat Texture: R: Rough r: Smooth Fur Color: B: Black b: White In this example, we will cross a heterozygous individual with another heterozygous individual. Their genotypes will be: BbRr x BbRr

Dihybrid Cross BbRr x BbRr First, you must find ALL possible gametes that can be made from each parent. Remember, each gamete must have one B and one R.

Dihybrid Cross BbRr x BbRr Possible gametes: BR Br bR br Next, arrange all possible gametes for one parent along the top of your Punnett Square, and all possible gametes for the other parent down the side of your Punnett Square…

Dihybrid Crosses: a cross that shows the possible offspring for two traits BbRr x BbRr BR bR br Br Fur Color: B: Black b: White Coat Texture: R: Rough r: Smooth Then, find the possible genotypes of the offspring

Dihybrid Crosses: a cross that shows the possible offspring for two traits BBRR BbRR BbRr BBRr BBrr Bbrr bbRR bbRr bbrr BbRr x BbRr Fur Color: B: Black b: White Coat Texture: R: Rough r: Smooth

How many of the offspring would have a black, rough coat? How many of the offspring would have a black, smooth coat? How many of the offspring would have a white, rough coat? How many of the offspring would have a white, smooth coat? BR bR br Br BBRR BbRR BbRr BBRr BBrr Bbrr bbRR bbRr bbrr Fur Color: B: Black b: White Coat Texture: R: Rough r: Smooth

How many of the offspring would have black, rough coat? How many of the offspring would have a black, smooth coat? How many of the offspring would have a white, rough coat? How many of the offspring would have a white, smooth coat? BR bR br Br BBRR BbRR BbRr BBRr BBrr Bbrr bbRR bbRr bbrr Phenotypic Ratio 9:3:3:1 Fur Color: B: Black b: White Coat Texture: R: Rough r: Smooth

More Practice… On the back of your notes… In pea plants, yellow seeds (Y) are dominant over green seeds (y), and rounded peas (R) are dominant over wrinkled peas (r). Cross a plant that is heterozygous for both traits with a plant that is homozygous recessive for both traits. Draw a Punnett square to show all possible offspring, and determine the genotypic and phenotypic ratios.

YyRr X yyrr YR yR yr Yr YyRr yyRr yyrr Yyrr

Genotypes: RRyy Gametes: RrYY

Karyotype

What type of cells does meiosis create? Monday, March 17th, 2014 Entrance task: _______________________________________________ For the 100th time… Daily Objective: What type of cells does meiosis create? By the end of today I should be able to… Describe the process of meiosis How are these cells different from normal cells? What is the process that makes normal cells?

Meiosis Think back to mitosis… What is the purpose of mitosis? Look through figure 11-15 on page 324 and 325. Look through page 326. In your notebook, answer the following questions: How does meiosis differ from mitosis? What are some similarities?

Mitosis Meiosis # Divisions: # Daughter Cells Produced: # Chromosome Sets: Location: Importance: Type of Reproduction: # Divisions: 1 # Daughter Cells Produced: 2 (identical) # Chromosome Sets: 2 (2N) – 1 from mom, 1 from dad Location: Body Cells (liver, muscle…) Importance: Produces identical cells for growth and repair Type of Reproduction: Asexual

Meiosis I: DNA replicates and Homologous chromosomes group to form tetrads. F f Meiosis h h Tetrad F f h h

f F But Ms. McClellan… Why should I care about crossing over? Crossing over: As homologous chromosomes pair up and form tetrads, they can exchange portions of their chromatids . f F But Ms. McClellan… Why should I care about crossing over? Because crossing over creates new allele combinations and allows for different types of offspring to be created

Homologous chromosomes separate and two new cells are formed

Meiosis II Meiosis Each daughter cell has ONE Allele of each gene instead of two… that is what makes them sex cells

Genetic Diversity Crossing over

Independent Assortment

Schedule HW: Finish genetics packet Tuesday: Study Guide over Transcription/translation/genetics/meiosis Wednesday: Review time Thursday: Test on Transcription/translation/genetics/meiosis Friday: Start Project

By the end of today I should be able to… Tuesday, March 18th, 2014 Entrance task: _______________________________________________ Without using your notes, Describe and draw a picture of crossing over. Daily Objective: By the end of today I should be able to… Explain the processes of crossing over and meiosis HAVE OUT YOUR SOAP OPERA GENETICS PLEASE

Please sit with your partner and have out your brochure. Wednesday, March 26th, 2014 Entrance task: ____________________________________________Daily Objective: Please sit with your partner and have out your brochure. By the end of today I should be able to… In your presentation, you will explain your disorder, what it causes, how it is transmitted, and any developments in treatments Describe what happens when chromosomes do not behave in a normal manner.