PUNNETT SQUARES AND MORE Chapter 9 Review

Define genotype. The genetic makeup of an organism

Define allele. An alternate form of a gene.

Define recessive. An allele that is hidden unless there are two of them

Define dominant. An allele that is fully expressed, it determines the phenotype of an organism.

What word refers to the physical appearance of an organism? Phenotype

When doing a test cross, an organism with unknown genotype is mated with one… That is homozygous recessive for a trait

What is a carrier? Someone heterozygous for a disease that shows no symptoms but CAN pass it on to offpsring.

John is blind, which is recessive. His parents are NOT blind. What are their genotypes? John’s? Parents: Heterozygous (for example: Bb) John: homozygous recessive (bb)

Name some recessive disorders. Deafness Albinism Cystic Fibrosis PKU Sickle Cell Tay Sachs

Name some dominant disorders. Dwarfism Althzimers Huntington’s disease High (hyper) cholesterol

Name some sex linked disorders. Color blindness Baldness Hemophilia Muscular dystrophy

If both alleles are expressed when someone is heterozygous, we call this ______. Codominance

What are the sex chromosomes of a man? XY

Is blood type codominance or incomplete? Codominance

How many sex chromosomes are in a sperm? One, either X or Y

Genes located on sex chromosomes are called Sex linked genes

Why do men get sex linked genes more often than women? Men only need to have one recessive allele (on their one X gene) in order to get the condition. Women have to inherit 2, one on each X.

What’s the name of the monk and what did he study? Gregor Mendel peas

What is heterozygous? Two different alleles for the same trait, one dominant and one recessive, written Bb.

What are the 3 types of fetal screening? Which is the LEAST invasive? Ultrasound, CVS, amniocentesis Ultrasound

Skin color, due to many genes, is caused by Polygenic inheritance

Brown eyes (B) are dominant to blue (b). What is the genotype of a heterozygous person. Bb

Brown eyes are dominant (B) to blue (b). White hair (W) is dominant to gray (w). What’s the genotype of blue eyes and grey hair? bbww

Brown eyes are dominant (B) to blue (b). White hair (W) is dominant to gray (w). genotype. Bbww = Brown eyes, gray hair

Purple flowers are dominant to white. Cross 2 heterozygous flowers. What’s the probability of a white flower? 1/4

Purple flowers are dominant to white. Cross a heterozygous with a white. What’s the probability of a white flower? 1/2

Purple flowers are dominant to white. Cross two homozygous purple flowers. What’s the probability of a white flower? 0

Brown eyes are dominant. A blue eyed child has brown eyed parents. What are their genotypes? Bb and Bb

Brown eyes are dominant to blue. Two heterozygous parents have a child. What is the probability that the child will have brown eyes? 3/4

Tall plants are dominant to short. A homozygous tall and short plant are crossed. What is the expected phenotypic ratio 4/4 tall

Purple flowers are dominant to white. Cross a heterozygous with a white. If there are 400 babies, how many will be white? 200

Incomplete dominance: Red (RR), Pink (Rr), white (rr). Cross a red and white and show your phenotypic ratio. 4/4 pink

Incomplete dominance: Red (RR), Pink (Rr), white (rr). Cross two pinks. How many offspring will be red? ¼ red

Incomplete dominance: Red (RR), Pink (Rr), white (rr). Cross 2 pinks and show the phenotypic ratio 1 red: 2 pink: 1 white

Incomplete dominance: Red (RR), Pink (Rr), white (rr). Cross 2 pinks and show the genotypic ratio 1 RR: 2 Rr: 1 rr

A man has heterozygous B blood, a woman has heterozygous A blood. What can their children have? A, B, AB, or O

Mom has type A blood. Baby has type O. Dad 1 has type AB and Dad 2 has type A. Who is the baby daddy? Dad 2

A person with type AB can receive what blood types? Any, AB is the universal receiver O is the universal donor.

Color blindness is sex-linked. Cross a normal man with a carrier woman. What are the chances a son will be blind? 1/2

Color blindness is sex-linked. Cross a normal man with a carrier woman. What are the chances a daughter will be blind? 0

Color blindness is sex-linked. Cross a blind man and a carrier. What are the chances a daughter will be a carrier? 1/2

Color blindness is sex-linked. Cross a blind man and a blind woman. What are the chances a daughter will be blind? 100%

Long (L) is dom to short (l) and yellow (Y) is dom to green (y). Cross a homozygous long heterozygous yellow with a short ?heterozygous yellow bird. How many are LlYy? 8/16

Using the same results, what proportion of offspring will have long yellow feathers? 12/16

Dark (D) is dom to light and Brown (B) is dom to blue. Cross two people heterozygous for BOTH traits. What is the prob of a light brown eyed child? 3/16

Dark (D) is dom to light and Brown (B) is dom to blue. Cross a heterozygous dark heterozygous brown with a light heterozygous brown. Show phenotypic ratios. 6/16 dark brown, 6/16 light brown, 2/16 dark blue, 2/16 light blue

In pedigrees, circles represent women

A filled in circle or square means Someone has the condition or disease Genotype is homozygous recessive (aa)

Horizontal lines between people indicate They are married or have offspring together