Heredity and Genetics

  1. Heredity is the passing of characteristics from ______to ______.
  1. Genetics is the branch of biology that…
  1. ______is the father of genetics.
  1. Why were garden peas good subjects for the study of genetics?

- have traits that are inherited by ______

- have male and female ______parts enclosed in the same structure

Mating could be done with the bristles of a brush!

- are ______, grow easily, mature quickly, and produce ______

  1. For each inherited characteristic, an individual has ______copies. (One copy is inherited from ______and one copy is inherited from ______.)
  1. Alleles are the ______of a gene. (For example, the two versions of the gene for pea seed color are ______and ______.)
  1. The expressed form of a trait is called ______. Ex: ______
  1. The trait that is not expressed if the dominant allele is present is called ______.

Ex: ______

9. What process is used to make gametes? ______

During fertilization each gamete ______, each gamete contributes one ______to the offspring.

So you get ½ of your genes from your mom and ½ of your genes from your dad!!

  1. Genotype is the…

Example:

  1. Phenotype is the …

Example:

  1. Homozygous- the two alleles present for a character are ______. Ex: ______
  2. Heterozygous- the two alleles present for a character are ______. Ex: ____

14. Labeling the Generations:

____ generation – ______generation

______Generation – first filial, offspring of the ______generation

______generation – second filial, offspring of the _____ generation

Probability

  1. ______is the likelihood that a specific event will occur.

3 Laws of Probability

First Law: Each trial of a chance event is ______of all other trials of the same

change event.

Application: What is the chance that you will roll a 1 the first time you roll a dice? ______

Problem: What is the chance that you will roll a 1 the second time you roll a dice? ______

Second Law (also called Law of Muliplication): The chance of independent events occurring together is the product of the chances for each independent event occurring separately.

Application: Two people have a coin. They are tossing the coins at the same time. What is the chance that both will come up heads?

Problem: What is the chance that both will come up tails? ______

Problem: What is the probability that a couple will have four boys in a row? ______

Problem: If one out of two students is female and one out of eight students is left handed and one out of 12 is red haired, what is the probability that the next person you will see will be left-handed, red-haired girl?

______

Third Law (also called Law of Addition): The probability of an event that can occur in two or more different ways is the sum of the separate possibilities of those ways.

Application: Two people have a coin. They are tossing the coins at the same time.

Problem: What is chance that one will come up heads and the other come up tails? ______

Now, let’s see if this works in the real world…

Each student will flip a penny 10 times and record the results. Based on probability, how many heads should there be? Tails?

Your results: Heads______Tails ______

Class results: Heads ______Tails ______

Which results are closest to your prediction based on probability? ______

Each student needs a penny and a partner!

Each student with their partner each flip their penny. Record the results whether it be 2 heads, 2 tails or 1 heads and 1 tails. Do this 20 times.

What is the predicted result based on probability? ______

Your results: HH_____ HT _____ TT_____

Class results: HH _____ HT _____ TT______

Which are closer to the predicted results?

Application Questions (Show your work)

a.Miguel has just received an IPOD as a gift. He has downloaded 3 country music songs,

1 rhythm and blues song, 5 rap songs, and 1 song that is the theme song to his favorite

movie. If the IPOD is set on playing these songs at random, what is the probability that

he will hear a country music song?

b.Sherri has a pocket full of colored candy jelly beans. She has 6 pink jelly beans, 3 yellow

jelly beans, 10 green jelly beans, and 1 orange jelly bean. What is the probability that

Sherri will select a green jelly bean and then, without replacing it, randomly select an

orange jelly bean from her pocket?

  1. What is a monohybrid cross?
  1. Monohybrid cross practice using Punnett Squares:
  1. Cross two heterozygous individuals. ______x ______

Gametes: ______

Genotypic ratio: ______

Phenotypic ratio: ______

  1. Cross a homozygous dominant with a homozygous recessive using the same trait.

______x ______

Gametes: ______

Genotypic ratio: ______

Phenotypic ratio: ______

  1. Cross a homozygous dominant with a heterozygous using the same trait.

______x ______

Gametes: ______

Genotypic ratio: ______

Phenotypic ratio: ______

18. What is a test cross?

What is a test cross used to determine?

Problem: Consider that tallness in pea plants is dominant to dwarfism. A horticulturalist has a tall plant, however is unaware of its genotype. She has a contract to produce all tall plants. Show the test cross she will have to make in order to be sure that the tall plant she uses to make offspring is a purebreeding tall plant. What are the possibilities with a tall plant?

Possible genotypes of her plant?Genotypes of the plant she will

cross with her plant? ______

______or ______