Bellwork: Create a 18 word sentence explaining how MEIOSIS relates to HEREDITY.

Build/Draw your Reebop Colored toothpick marker toothpick

 HAPPY TUESDAY  Bellwork: Set up page 42 in your notes for “Genetics”. EQ: How can I describe genetic traits?

Science Fact of the Day: Sheep, goats, and the octopus have almost rectangular-oval pupils in their eyes.

A trait is a specific characteristic that varies from one individual to another. Example…

Biological inheritance is determined by factors that are passed from one generation to the next. The chemical factors that determine traits are called genes. The different forms of a gene are called alleles.

T = Dominant t = Recessive The principle of dominance states that some alleles are dominant while others are recessive. The dominant allele will always be expressed. A capital letter is used to represent a dominant allele. T = Dominant t = Recessive

T = Dominant t = Recessive The recessive allele will only be expressed when the dominant allele for the trait is not present. A lower case letter is used to represent a recessive allele. T = Dominant t = Recessive

BB Bb bb Brown Eyes vs Blue eyes A phenotype is an organism’s physical characteristics. A genotype is an organism’s genetic makeup. Two organisms can have the same phenotype but different genotypes. Brown Eyes vs Blue eyes BB Bb bb

Organisms that have two of the same alleles for a trait are homozygous Organisms that have two different alleles for a trait are heterozygous. Homozygous organisms are true-breeding/purebred for a trait. Heterozygous organisms are hybrid for a trait. BB Bb bb BB Bb bb

The way in which alleles separate during meiosis is completely random The way in which alleles separate during meiosis is completely random. This is also known as the principle of independent assortment.

Happy Wednesday 11/18/15 Bellwork: Scientists have discovered a new creature! Seen to the right… REEBOP CREATURE! EE = Two Eyes, Ee = Two Eyes, ee = one eye AA = Two horns, Aa = Two horns, aa = one horn What are the possible genotypes for this creature? What are some creature phenotypes that can be observed from the picture?

Standard: B6F - Predict possible outcomes of genetic combinations such as monohybrid crosses. Essential Question: How can I predict genetic outcomes?

Can you identify your own genotypes and phenotypes? Hairline: Widow’s peak is dominant to straight hairline Eye Shape: Almond eyes is dominant to round eyes

Eyelash Length: Long eyelashes is dominant to short eyelashes Tongue Rolling: CAN roll the tongue is dominant to cannot

Hitchhiker’s Thumb: Hitchhiker’s thumb is dominant to straight thumb Lip Thickness: Thick lips are dominant to thin lips

The results of genetic crosses can be explained by probability The results of genetic crosses can be explained by probability. Probability is the likelihood that a particular event will occur.

The gene combinations that might result from a genetic cross can be determined by drawing a diagram known as a Punnett square.

The letters in the Punnett square represent alleles The letters in the Punnett square represent alleles. Punnett squares are used to predict and compare the genetic variations that will result from a cross.

1st Step = Identify what letter is being used Punnett Square Steps 1st Step = Identify what letter is being used What would be the possible outcomes for the offspring of a cross between pink flower (PP) and a white flower (pp)? “P” and “p”

2nd Step = Assign the trait for each letter. Punnett Square Steps 2nd Step = Assign the trait for each letter. What would be the possible outcomes for the offspring of a cross between pink flower (PP) and a white flower (pp)? P= PINK p = WHITE

3RD Step = Match what letters are being used for each parent/gender. Punnett Square Steps 3RD Step = Match what letters are being used for each parent/gender. What would be the possible outcomes for the offspring of a cross between pink flower (PP) and a white flower (pp)? = PP = pp DAD MOM

Let’s sum it up….. 1st = Identify what letters are being used. 2nd = Assign the trait for each letter. 3rd = Match what letters are being used for each parent/gender. 4th = Now fill in your Punnett Square.

P P P = Pink p = White DAD = PP MOM = pp Pp p Pp p Pp Pp Punnett Square practice… 1. What would be the possible outcomes for the offspring of a cross between pink flower (PP) and a white flower (pp)? P P P = Pink p = White DAD = PP MOM = pp Pp p Pp p Pp Pp **When using the letters like “P and p” OR “C and c”, draw the lowercase letter in cursive or just make sure you make them look different. Otherwise, you might confuse the dominant for the recessive **

F = Long f = Short DAD = Ff MOM = ff F f Ff ff f f Ff ff 2. Long fingers are dominant (F) to short fingers (f). Complete the Punnett square for a homozygous recessive mom and a heterozygous dominant dad. F = Long f = Short DAD = Ff MOM = ff F f Ff ff f f Ff ff

L L L = Long l = Short DAD = LL MOM = ll l Ll Ll l Ll Ll 3. In a plant, long stems are dominant (L) to short stems (l). If a homozygous dominant flower and a homozygous recessive plant are crossed, what would be the phenotypic ratio of their offspring? L L L = Long l = Short DAD = LL MOM = ll l Ll Ll l Ll Ll

C c C = Straight c = Curly DAD = Cc MOM = Cc C CC Cc c Cc cc 4. Straight hair (C) is dominant to curly hair (c). What would be the probability that a child would have curly hair if both parents are heterozygous dominant? C c C = Straight c = Curly DAD = Cc MOM = Cc C CC Cc c Cc cc

T t T = Hitchhiker t = Straight DAD = Tt MOM = tt Tt tt t t Tt tt 5. Having a hitchhiker's thumb is a dominant trait (T). If a woman with a straight thumb has a child with a man who is heterozygous for the trait, what are the chances their child will have a hitchhiker's thumb? T t T = Hitchhiker t = Straight DAD = Tt MOM = tt Tt tt t t Tt tt

P = Purple p = White DAD = Pp MOM = Pp P p P PP Pp Pp pp p 6. What would the phenotypic and genotypic ratios be for two purple (Pp) flowers that were bred together? P = Purple p = White DAD = Pp MOM = Pp P p P PP Pp Pp pp p

Punnet Square Alien Worksheet