How do we get blended traits Incomplete dominance

How do we get blended traits? Incomplete ____________dominance The dominant allele will not fully cover up a recessive allele and the trait will be a result of the two blending or mixing together.

How do we get blended traits? In carnations, incomplete dominance can be seen in flower color: � red 1. Cross two pink carnations ______x______ Rr Rr R R r (RR) pink (Rr) white (rr) r RR Rr Rr rr A. Possible genotypes of offspring: RR= ¼ Rr= 2/4 Rr=1/4 B. Possible Red= ¼phenotypes of offspring: Pink= 2/4 White= ¼

How do we get blended traits? 2. Cross a red and a pink carnation: RR Rr _______x_______ A. Possible genotypes of offspring: RR: 2/4 Rr: 2/4 R R RR RR r Rr Rr R B. Possible phenotypes of offspring: Red: 2/4 Pink: 2/4

Practice Problems: Incomplete Dominance- pg. 4 In humans, hair texture is due to an incompletely dominant trait. Straight hair (H) is incompletely dominant to curly hair (h). When crossed, they produce a heterozygous individual with wavy hair (Hh). phenotypes and the corresponding List all possible genotype for hair texture. Straight (HH), Wavy (Hh), and Curly (hh) ____________________

Practice Problems: Incomplete Dominance- pg. 4 Using a Punnett square, cross a curlyhaired person with a wavy-haired person. Hh hh h Hh hh HH: 0/4 Hh: 2/4 hh: 2/4 Straight: 0/4 Wavy: 2/4 Curly: 2/4 0: 2: 2 What is the genotypic ratio of the offspring? ____________ What is the phenotypic ratio of the offspring? 0: 2: 2 ____________

Practice Problems: Incomplete Dominance pg. 4 In guinea pigs, white fur (F) is incompletely dominant over yellow fur (f). When crossed they produce heterozygous offspring with creamcolored fur (Ff). List all possible phenotypes and the corresponding genotype for fur. Ffcolor. White: FF Cream: yellow: ff ________________

Practice Problems: Incomplete Dominance pg. 4 • Using a Punnet Square, cross two guinea pigs with cream-colored hair. ________ X _________ Ff Show your lists of genotypes & phenotypes here! F f F FF Ff ff Genotypes: FF: ¼ Ff: 2/4 ff: ¼ Phenotypes: White: ¼ Cream: 2/4 Yellow: ¼ What is the genotypic ratio of the offspring? 1: 2: 1 ____________ What is the phenotypic ratio of the offspring? ____________

Can we express 2 traits at once? Pg. 5 Codominance - When two different alleles are expressed equally _____ , at the same time (neither one is

Can we express 2 traits at once? Pg. 5 Codominant alleles are written as capital letters with superscripts or subscripts (HR or B 1). Since the trait is inherited from both parents, it is important to still use two ‘sets of letters’ as seen below: The allele for red hair (HR) is codominant with the allele for white hair (HW) in cattle. Cattle that have the genotypes HRHW are called roan because their hair is a mixture of red and white hairs.

Can we express 2 traits at once? HRHR = Red HRHW = roan HWHW = White Cross a red cow and a white bull: HR HW HRHW HW HRH W 1. Possible genotypes of offspring: HRHR : 0/4 HRHW: 4/4 HWHW: Genotypic Ratio: 0/4 0: 4: 0 2. Possible phenotypes of offspring: Red: 0 Roan: 4 White: 0 Phenotypic Ratio: 0: 4: 0

Can we express 2 traits at once? HRHR = Red HRHW = roan HWHW = White Cross a roan cow and a roan bull: HR HR H RH W HW HW HW A. Possible genotypes of offspring: HRHR: 1/4 Genotypic HRHW: 2/4 Ratio: HWHW: 1/4 1: 2: 1 B. Possible phenotypes of Red: 1/4 Roan: 2/4 White 1/4 offspring: : Phenotypic Ratio: 1: 2: 1

What are some examples of Codominance in humans? In humans, red blood cells contain a protein called hemoglobin. It is the hemoglobin that gives the red blood cell its color and ability to pick up oxygen and carry to other cells.

What is Sickle Cell Anemia? https: //www. youtube. com/watch? v=Qd 0 Hr. Y 2 N lw. Y

How is sickle cell anemia inherited? Sickle cellsufferer _____ are homozygous (HSHS) s � Because all of their blood cells are affected by the sickle cell gene, these people are severely afflicted by the disease. Their red blood cells can becomes sickle shaped, rigid and live about 20 days. They also tend to get stuck in narrow blood vessels, which may cause complications.

How is sickle cell anemia inherited? Sickle cell carrier ______ are AH S ) heterozygous (H s � These carriers produce normal blood cells and sickle cell blood cells. Usually these people do not experience severe affects of this disease. Sickle cell anemia is more common in some parts of the world because being a carrier causes Malaria resistant. In places where Malaria is a problem, having 1 copy of the sickle cell gene is beneficial.

How is sickle cell anemia inherited? Cells with normal _____ hemoglobin (no sickle cell anemia) are homozygous (HAHA) � Their red blood cells are disk shaped, soft/flexible and live for about 120 days.

How is sickle cell anemia inherited? HA Complete a punnett square to determine the chances of two sickle cell carriers having a homozygous normal child? A HS H H Genotype of parents: ____ x ______ HA HS HA HA HA HS HS H S HAHA ¼ Normal : HAHS: 2/4 Carriers HSHS: ¼ Sufferer 25%

Practice Problems: Codominance pg. 7 In horses, pale cream color (C) is codominant to chestnut color (C ). When crossed, they produce a heterozygous individual called a palomino (C C ) which has a cream & chestnut coat. List all possible phenotypes and the corresponding Pale (CC) Palomino genotype for coat color. (CC’) Chesnut ___________________ (C’C’) _____

Practice Problems: Codominance pg. 7 Using a Punnett square, cross a palomino horse with another palomino horse. C C’ C CC CC’ C’C’ C’ CC’ ______x______ Show your lists of genotypes & phenotypes _ here! CC= ¼ Pale CC’= 2/4 Palomino C’C’= ¼ Chesnut 1: 2: 1 What is the genotypic ratio of the offspring? _______ 1: 2: What is the phenotypic ratio of the offspring? ______ 1

Practice Problems: Codominance pg. 7 In chickens, black feather color (FB) is codominant to white feather color (FW). The heterozygous individual is a combination of black and white feathers that results in a checkered pattern (FBFW). List all possible phenotypes and the corresponding B ), Checkered genotype color. Black (FBfor. Ffeather (FBFW) White WF W ) (F___________________

Practice Problems: Codominance pg. 7 Using a Punnett square, cross a checkered chicken with a black chicken. FB FBF FB _____x_____ W Show your lists of genotypes & phenotypes B F here! B B : 2/4 Black FBF F F W FBFW: 2/4 Checkered WFW: 0/4 White FBF F W FW FB FB FB B F 2: 2: 0 What is the genotypic ratio of the offspring? _____ 2: 2: 0 What is the phenotypic ratio of the offspring? _____