Patterns of Heredity 4.1 Living things inherit traits in patterns. 4.2 CHAPTER NEW CHAPTER 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 DNA is divided during meiosis. 4.4 Cells use DNA and RNA to make proteins. CHAPTER OUTLINE CHAPTER RESOURCES

4.1 CALIFORNIA Content Standards Living things inherit traits in patterns. CALIFORNIA Content Standards 7.2.c Students know an inherited trait can be determined by one or more genes. 7.2.d Students know plant and animal cells contain many thousands of different genes and typically have two copies of every gene. The two copies (or alleles) of the gene may or may not be identical, and one may be dominant in determining the phenotype while the other is recessive. sexual reproduction gene heredity allele phenotype genotype dominant recessive CHAPTER RESOURCES SECTION OUTLINE

4.1 Living things inherit traits in patterns. alleles a gene Offspring inherit alleles, which are forms of genes, from their parents. Alleles can be dominant or recessive. sexual reproduction gene The alleles you have are your genotype; the observable characteristics that come from your genotype are your phenotype. heredity allele phenotype genotype dominant recessive SIMULATION Try a virtual version of Mendel’s experiment. CLASSZONE.COM CHAPTER RESOURCES SECTION OUTLINE

Patterns of heredity can be predicted. 4.2 Patterns of heredity can be predicted. CALIFORNIA Content Standards 7.2.b Students know sexual reproduction produces offspring that inherit half their genes from each parent. 7.2.c Students know an inherited trait can be determined by one or more genes. 7.2.d Students know plant and animal cells contain many thousands of different genes and typically have two copies of every gene. The two copies (or alleles) of the gene may or may not be identical, and one may be dominant in determining the phenotype while the other is recessive. Punnett square probability CHAPTER RESOURCES SECTION OUTLINE

Patterns of heredity can be predicted. 4.2 Patterns of heredity can be predicted. Punnett squares show possible outcomes of heredity. Punnett square Percentages can be used with Punnett squares to express the probability of each possible outcomes. probability B b B = black fur b = brown fur BB Bb bb SIMULATION Predict offspring traits with virtual Punnett squares. CLASSZONE.COM CHAPTER RESOURCES SECTION OUTLINE

DNA is divided during meiosis. 4.3 DNA is divided during meiosis. CALIFORNIA Content Standards 7.2.a Students know the differences between the life cycles and reproduction methods of sexual and asexual organisms. 7.2.b Students know sexual reproduction produces offspring that inherit half their genes from each parent. gamete egg sperm fertilization meiosis CHAPTER RESOURCES SECTION OUTLINE

DNA is divided during meiosis. 4.3 DNA is divided during meiosis. Meiosis is a type of cell division needed for sexual reproduction. gamete During meiosis, cells divide twice to produce gametes. egg Male and female gametes join when fertilization occurs. sperm fertilization meiosis Meiosis I 1n CHAPTER RESOURCES Meiosis II SECTION OUTLINE

Cells use DNA and RNA to make proteins. 4.4 Cells use DNA and RNA to make proteins. CALIFORNIA Content Standards 7.2.e Students know DNA (deoxyribonucleic acid) is the genetic material of living organisms and is located in the chromosomes of each cell. replication RNA CHAPTER RESOURCES SECTION OUTLINE

Cells use DNA and RNA to make proteins. 4.4 Cells use DNA and RNA to make proteins. DNA contains a code that enables a cell to make RNA and proteins. replication Replication copies the code before a cell divides. RNA • DNA’s triplet code enables a cell to code for proteins. • A cell’s mRNA, tRNA, and ribosomes translate the code into a sequence of amino acids. • The amino acids form a protein needed for cell function. CHAPTER RESOURCES SECTION OUTLINE

4.1 Living things inherit traits in patterns. I. Living things inherit traits in patterns. 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 dominant 2. Mendel’s Conclusions recessive D. Alleles interact to produce traits. 1. Phenotype and Genotype CHAPTER RESOURCES 2. Dominant and Recessive Alleles KEY CONCEPT SUMMARY

Patterns of heredity can be predicted. 4.2 Patterns of heredity can be predicted. II. Patterns of heredity can be predicted. Punnett square A. Punnett squares show possible outcomes for inheritance. probability B. Percentages can express the probability of outcomes. CHAPTER RESOURCES KEY CONCEPT SUMMARY

DNA is divided during meiosis. 4.3 DNA is divided during meiosis. III. DNA is divided during meiosis. gamete A. Meiosis is necessary for sexual reproduction. egg B. Cells divide twice during meiosis. sperm 1. Meiosis I fertilization 2. Meiosis II meiosis 3. Combinations of Alleles C. Meiosis and mitosis differ in some important ways. CHAPTER RESOURCES KEY CONCEPT SUMMARY

Cells use DNA and RNA to make proteins. 4.4 Cells use DNA and RNA to make proteins. IV. Cells use DNA and RNA to make proteins. replication A. DNA is the information molecule. RNA 1. Proteins and Amino Acids 2. DNA and the Genetic Code B. Replication produces two copies of DNA. C. RNA is needed to make proteins. 1. Types of RNA 2. Transcription 3. Translation CHAPTER RESOURCES KEY CONCEPT SUMMARY

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