2. Genetics Basics (10.2) State Standard
2C. Using Mendel’s laws, explain the role of meiosis in reproductive variability.

3. Mendel followed various traits in the pea plants he bred.
Chapter 10
Sexual Reproduction and Genetics
10.2 Mendelian Genetics
How Genetics Began
The passing of traits to the next generation is called inheritance, or heredity.
Mendel performed cross-pollination in pea plants which are true breeding and easy to grow/observe
Mendel followed various traits in the pea plants he bred.

4. The parent generation is also known as the P generation.
Chapter 10
Sexual Reproduction and Genetics
10.2 Mendelian Genetics
The parent generation is also known as the P generation.

5. The second filial (F2) generation is the offspring from the F1 cross.
Chapter 10
Sexual Reproduction and Genetics
10.2 Mendelian Genetics
The offspring of this P cross are called the first filial (F1) generation.
The second filial (F2) generation is the offspring from the F1 cross.

6. Mendel studied seven different traits.
Chapter 10
Sexual Reproduction and Genetics
10.2 Mendelian Genetics
Mendel studied seven different traits.
Seed or pea color
Flower color
Seed pod color
Seed shape or texture
Seed pod shape
Stem length
Flower position

7. Dominant - easily covers recessive alleles
Chapter 10
Sexual Reproduction and Genetics
10.2 Mendelian Genetics
Genes in Pairs
Allele
An alternative form of a single gene passed from generation to generation
Dominant easily covers recessive alleles
Recessive easily masked by dominant alleles

8. Dominance – represented by a capital letter
Chapter 10
Sexual Reproduction and Genetics
10.2 Mendelian Genetics
Dominance
Dominance – represented by a capital letter
Recessive – represented by a lower case letter
An organism with two of the same alleles for a particular trait is homozygous.
An organism with two different alleles for a particular trait is heterozygous.

9. Genotype and Phenotype
Chapter 10
Sexual Reproduction and Genetics
10.2 Mendelian Genetics
Genotype and Phenotype
An organism’s allele pairs are called its genotype.
The observable characteristic or outward expression of an allele pair is called the phenotype.
An organism may have the same phenotype but either be homozygous or heterozygous.

10. Mendel’s Law of Segregation
Chapter 10
Sexual Reproduction and Genetics
10.2 Mendelian Genetics
Mendel’s Law of Segregation
Two alleles for each trait separate during meiosis.
During fertilization, two alleles for that trait unite.
Heterozygous organisms are called hybrids.

11. Chapter 10
Sexual Reproduction and Genetics
10.2 Mendelian Genetics
Monohybrid Cross
A cross that involves hybrids for a single trait is called a monohybrid cross.

12. Dihybrids are heterozygous for both traits.
Chapter 10
Sexual Reproduction and Genetics
10.2 Mendelian Genetics
Dihybrid Cross
The simultaneous inheritance of two or more traits in the same plant is a dihybrid cross.
Dihybrids are heterozygous for both traits.

13. Law of Independent Assortment
Chapter 10
Sexual Reproduction and Genetics
10.2 Mendelian Genetics
Law of Independent Assortment
Random distribution of alleles occurs during gamete formation
Genes on separate chromosomes sort independently during meiosis.
Each allele combination is equally likely to occur.

14. Predict the possible offspring of a cross between two known genotypes
Chapter 10
Sexual Reproduction and Genetics
10.2 Mendelian Genetics
Punnett Squares
Predict the possible offspring of a cross between two known genotypes
Punnett Squares

15. Punnett Square—Dihybrid Cross
Chapter 10
Sexual Reproduction and Genetics
10.2 Mendelian Genetics
Punnett Square—Dihybrid Cross
Four types of alleles from the male gametes and four types of alleles from the female gametes can be produced.
The resulting phenotypic ratio is 9:3:3:1.

16. Genetic Recombination
Chapter 10
Sexual Reproduction and Genetics
Genetic Recombination
The new combination of genes produced by crossing over and independent assortment
Combinations of genes due to independent assortment can be calculated using the formula 2n, where n is the number of chromosome pairs.

23. In humans, detached earlobes are dominant over attached earlobes.
Make a letter key for this trait (including what each letter stands for).
Create a Punnett Square to show a cross between a person who is hybrid & a person who has attached earlobes.
Show the percentages of each possible genotype
Show the percentages of each possible phenotype

24. Name the person known as the father of genetics.
Chapter 10
Sexual Reproduction and Genetics
Chapter Diagnostic Questions
Name the person known as the father of
genetics.
Felix Mendelssohn
Gregor Mendel
Dr. Reginald Punnett
Albert Einstein

25. Which term refers to the outward expression of an allele pair?
Chapter 10
Sexual Reproduction and Genetics
Chapter Diagnostic Questions
Which term refers to the outward expression
of an allele pair?
gamete
hybrid
phenotype
genotype

26. What is the name for different forms of a
Chapter 10
Sexual Reproduction and Genetics
10.2 Formative Questions
What is the name for different forms of a
single gene that are passed from generation
to generation?
alleles
genotypes
phenotypes
traits

27. Which pair of alleles is heterozygous?
Chapter 10
Sexual Reproduction and Genetics
10.2 Formative Questions
Which pair of alleles is heterozygous? RR Rr rr yR

28. In rabbits, gray fur (G) is dominant to black
Chapter 10
Sexual Reproduction and Genetics
10.2 Formative Questions
In rabbits, gray fur (G) is dominant to black
fur (g). If a heterozygous male is crossed with
a heterozygous female, what is the phenotypic
ratio of the possible offspring?
1:1
1:2:1
2:1
3:1

29. Which explains how the shuffling of genes
Chapter 10
Sexual Reproduction and Genetics
10.3 Formative Questions
Which explains how the shuffling of genes
during meiosis results in billions of possible
combinations?
crossing over
gene linkage
genetic recombination
independent segregation

30. Two genes on the same chromosome may become separated during meiosis.
Chapter 10
Sexual Reproduction and Genetics
10.3 Formative Questions
True or False
Two genes on the same chromosome may
become separated during meiosis.

31. 1/4 1/2 1 For human eye color, brown is dominant and
Chapter 10
Sexual Reproduction and Genetics
Standardized Test Practice
For human eye color, brown is dominant and
blue is recessive. If a husband is heterozygous
and his wife has blue eyes, what is the
probability that their child will have blue eyes?
1/4
1/2 1