Transcript Patterns of Heredity

CHAPTER
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Patterns of Heredity
the BIG idea
In sexual reproduction, genes are passed from parents to offspring in
predictable patterns.
4.1 Living things inherit traits in patterns.
4.2 Patterns of heredity can be predicted.
4.3 Meiosis is a special form of cell division.
CHAPTER OUTLINE
CHAPTER RESOURCES
4.1
CHAPTER HOME
KEY CONCEPT
Living things inherit traits in patterns.
Offspring inherit alleles, which are
forms of genes, from their
parents. Alleles come on
chromosome pairs and can be
dominant or
recessive. The alleles you have
are your genotype; the observable
characteristics that come from
your genotype are your
phenotype.
a gene
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alleles VOCABULARY
sexual reproduction
gene
heredity
allele
phenotype
genotype
dominant
recessive
CHAPTER
RESOURCES
SECTION
OUTLINE
4.2
CHAPTER HOME
KEY CONCEPT
Patterns of heredity can be predicted.
Punnett squares show possible outcomes of heredity.
Ratios and percentages can be used with Punnett
squares to express the probability of particular
outcomes.
VOCABULARY
Punnett square
ratio
probability
percentage
B
b
BB
Bb
B = black fur
b = brown fur
B
SIMULATION
b
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CHAPTER
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SECTION
OUTLINE
4.3
CHAPTER HOME
KEY CONCEPT
Meiosis is a special form of cell division.
• At the beginning of meiosis I, the parent cell has two
copies of each chromosome pair.
• During meiosis I, the homologs of the chromosome
pair separate; there are two cells, each with two copies
of one homolog from each pair.
• During meiosis II, the two copies of each homolog
separate; each daughter cell has one homolog.
VOCABULARY
gamete
egg
sperm
fertilization
meiosis
Meiosis I
1n
1n
1n
1n
CHAPTER
RESOURCES
Meiosis II
SECTION
OUTLINE
4.1
KEY CONCEPT
CHAPTER HOME
Living things inherit traits in patterns.
I. Living things inherit traits in patterns.
VOCABULARY
sexual reproduction
A. Parents and offspring are similar.
gene
B. Genes are on chromosome pairs.
heredity
C. Gregor Mendel made some important
discoveries about heredity.
allele
phenotype
1. One Example
genotype
2. Mendel’s Conclusions
dominant
D. Alleles interact to produce traits.
1. Phenotype and Genotype
2. Dominant and Recessive Alleles
recessive
CHAPTER
RESOURCES
KEY CONCEPT
SUMMARY
4.2
KEY CONCEPT
CHAPTER HOME
Patterns of heredity can be predicted.
II. Patterns of heredity can be predicted.
VOCABULARY
Punnett square
A. Punnett squares show possible outcomes for
inheritance.
ratio
B. Ratios and percentages can express the
probability of outcomes.
percentage
probability
CHAPTER
RESOURCES
KEY CONCEPT
SUMMARY
4.3
KEY CONCEPT
CHAPTER HOME
Meiosis is a special form of cell division.
III. Meiosis is a special form of cell division.
A. Meiosis is necessary for sexual reproduction.
B. Cells divide twice during meiosis.
VOCABULARY
gamete
egg
sperm
1. Meiosis I
fertilization
2. Meiosis II
meiosis
C. Meiosis and mitosis differ in some important
ways.
CHAPTER
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KEY CONCEPT
SUMMARY
CHAPTER HOME
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