Vassell_Genetics Practice (Slides +Questions))

Gene = Eye Color

​

Allele = Blue Eyes

​

Allele = Brown Eyes​

​

​Allele = a variant form of a gene

​

​We use letters to show if the allele is dominant or recessive.

​

Dominant alleles only need one to show: AA or Aa

Recessive alleles need two to show: aa​

​Used to predict all possible allele combinations and their frequencies in offspring.

​

​Punnett Squares

​

​These examples we have just looked at traits that are controlled by only two alleles

• Long tail or short tail

• Tall plant or short plant

• Green or yellow peas in plants

• Red or white flowers

  ​

​Mendelian pattern of inheritance = traits only have two possible alleles with one dominant and one recessive AKA complete dominance

​

Non-mendelian inheritance is controlled by multiple alleles​

​

​

​

Neither allele is dominant.

​

The heterozygous genotype will show a third phenotype = blend of the other two​

​

​Incomplete Dominance

​

Occurs when both alleles are expressed equally

​

​

​

​Codominance

​

​Roaning occurs when the coat of the animal has white hairs and the hairs of any other colored mixed in together.

​

Codominance can also create spots/stripes​

Traits that are determined by multiple genes

​

Hundreds of genes acan be involved

​

​Polygenic Traits

​

A single gene affects multiple phenotypes

​

Marfan syndrome: genetic disease that affects the development of connective tissue during fetal development, so it has a wide range of effects throughout the body​

​

​Elongated arms, legs fingers; joints could be extra flexible; affects eyesight; increases likelihood of cardiovascular issues

​Pleiotropy

​

Multiple Choice

G = green, g = yellow
The genotype for a yellow plant is...

• GG

• Gg

• gg

• all of the choices result in yellow

Multiple Choice

T = tall an t = short
TT and Tt would result in  the following phenotype

• short
• tall
• both tall and short
• neither tall or short

Multiple Choice

B = brown fur  b = white fur
In the punnett square, what is the probability for white fur? 

• 0%
• 25%
• 50%
• 75%

Multiple Choice

Purebred is another word for __________, while hybrid is another word for __________.

• dominant; recessive
• recessive; dominant
• homozygous; heterozygous
• heterozygous; homozygous

Multiple Choice

Aa is

• homozygous (purebred)
• heterozygous (hybrid)

Multiple Choice

Which of the following is a phenotype?

• Aa
• red hair
• heterozygous
• DNA

Multiple Choice

Squidward has light blue skin, and his genotype for this trait is Bb. Would Squidward be considered a purebred or hybrid for light blue skin?

• Purebred
• Hybrid

Multiple Choice

An offspring will receive how many alleles from each parent to determine a specific trait?

• one
• two
• three
• five

Multiple Choice

Magda is a tall, 11 year old drummer. She has a scar on her right cheek. She is good at swimming. Which of her traits did Magda most likely inherit?

• height
• the scar
• ability to swim
• ability to play drums

Multiple Choice

Two brown eyed parents (Bb) have a baby. What is the chance the baby is blue eyed?

• 0 %
• 25%
• 50%
• 75%

Multiple Choice

How many children did individuals I-1 and I-2 have?

• 2

• 4

• 6

• 8

Multiple Choice

How many girls did II-1 and II-2 have?

• 1

• 2

• 3

• 4

Multiple Choice

A calico cat shows both the traits for orange fur and black fur. What kind of allele expression is this?

• Incomplete Dominance

• Co dominance

• Independent assortment

• Recessive inheritance

Multiple Choice

This type of inheritance pattern is a MIXTURE of both traits.

• incomplete dominance
• co-dominance
• complete dominance
• recessive pattern

Multiple Choice

What you see, or the physical appearance.

• Genotype
• Phenotype
• Homozygous
• Heterozygous