1. 1 THE WORK OF GREGOR MENDEL OBJECTIVES: 11.1 Describe how Mendel studied inheritance in peas. Summarize Mendel’s conclusion about inheritance. Explain the principle of dominance. Describe what happens during segregation.

2. 2 ________ is the scientific study of heredity. An Austrian monk, ______, was important in understanding biological inheritance. Mendel carried out his work with ordinary garden ____. He found the ____ parts of the plant to produce _____ and the _________ parts to produce _____.

3. 3 During _______ reproduction male and female reproduction cells join in a process called ___________. Pea plants are usually _____ __________, which means that the sperm cells in pollen fertilize the egg cells in the same flower. The new plants inherit the ______ of a single parent. Mendel had ____ breeding plants, which mean if they self-pollinate they produce offspring that are ___________ to themselves.

4. 4 One type of pea plant produce only ____ plants, another only _____. One line produced only _______seeds, another only ______. Mendel wanted to join the sperm and egg from two different plants (_____-___________). To do this he had to prevent self-pollination by cutting of the pollen-bearing male parts and then dusted the pollen onto another plant.

5. 5 Mendel studied _____ different traits. A trait is a ________ _________, such as seed color or plant height. Each trait was contrasting such as tall or short. The original plants are the __ (parental) generation, the first generation is the __(first filial) generation. ______ is Latin for son and _____ is Latin for daughter.

6. 6 The offspring of crosses between parents with different traits are called ________.

7. 7 Mendel concluded two things from his experiments. 1.Biological inheritance is determined by factors that are passed from one generation to the next (we call them _____). _______are different forms of the gene for the same trait. (hair color, etc). 2. The _________ __ _________ states that some alleles are dominant and others are recessive.

8. 8

9. 9 An organism with a __________ allele for a trait will always be expressed. An organism with a ___________ allele for trait will only be expressed only when the _______ allele is not present. Mendel allowed the __ generation to self-pollinate to see if the recessive trait had disappeared. What he got was a ___ (ratio), tall to short.

10. 10 When each F1 plant flowers and produces _______, the two alleles ________ from each other so that each gamete carries only a single copy of each gene. Therefore, each F1 plant produces two types of gametes-those with the allele for ________and those with allele for _________.

11. 11 Monohybrid cross

12. 12 PROBABILITY AND PUNNETT SQUARES OBJECTIVES: 11.2 Explain how geneticists use the principles of probability. Describe how geneticists use punnett squares.

13. 13 The likelihood that a particular event will occur is called ____________. The principle of probability can be used to ______ the outcomes of genetic crosses.

14. 14 Punnett square

15. 15 A ______ square show the combinations of genes that might result from a genetic cross. ________ squares are used to predict and compare the genetic variations that will result from a cross. Organisms that have two identical alleles for a trait (__ or __) are said to be _____________. Organisms that two different alleles for the same trait are said to be __________ (__).

16. 16 The _________ of an organism is its physical characteristics. The ________ of an organism is its genetic makeup. Some organism can have the same phenotypes but different genotypes.

17. 17 EXPLORING MENDELIAN GENETICS OBJECTIVE: 11.3 Explain the principle of independent assortment. Describe the inheritance patterns that exist aside from simple dominance. Explain how Mendel’s principles app.ly to all organisms.

18. 18 Mendel next crossed a true breeding plant (one that produces a plant like it self) with a genotype of ____ and another true breeder ____. These plants are homozygousfor the traits. This shows that the yellow and round are dominant over the alleles for green and wrinkled.

19. 19 Mendel knew that the F 1 generation had a genotype of _____. This punnett square shows that alleles _________ ____________ of each other. This principle is know as __________ ___________.

20. 20 The principle of independent assortment states that ______ for different _______can segregate independently during the formation of _______. Independent assortment helps to account for the many genetic __________ observed in plants and animals, and other organisms

21. 21 Mendel’s principles 1.The inheritance of biological characteristics is determined by individual units know as genes. Genes are passed from parent to offspring. 2.In cases in which two or more forms (alleles) of the gene for a single trait exist, some forms of the gene may be dominant and others may be recessive. 3.In most sexually reproducing organisms, each adult has two copies of each gene – one from each parent. These genes are segregated from each other when gametes are formed. 4.The alleles for different genes usually segregate independently of one another.

22. 22 There are exceptions to most of Mendel’s principles. Not all genes show the simple patterns of dominant and recessive alleles. Some alleles are neither dominant nor recessive, and many traits are controlled by multiple alleles or multiple genes. Incomplete dominance is where one allele is not completely dominant over another. The phenotype is some where in between (pink flowers).

23. 23

24. 24 ___________ is when both alleles contribute to the phenotype. Erimiette

25. 25 Many genes have more than two alleles and are therefore said to have _________ alleles. An individual ___ ___have more than two alleles for a trait. This means there are more than two alleles in the population.

26. 26 Traits that are produced by the interaction of several genes are said to be polygenic traits. There are three genes that are involved in making the redish-brown pigment in the eyes of fruit fly (Drosophila melanogaster)

27. 27 MEIOSIS OBJECTIVES: 11.4 Contrast the chromosome number of body cells and gametes. Summarize the events of meiosis. Contrast meiosis and mitosis.

28. 28 __________ means that each chromosome has corresponding chromosome from each parent

29. 29 A cell that contains both sets of homologous chromosomes is said to _______ (__). A cell (gamete) that has only one set of chromosomes are said to be ________ (_)

30. 30 ________ is a process of reduction division in which the number of chromosomes per cell is cut in ____ through the separation of homologous chromosomes in a _______ cell. Meiosis usually involves two distinct divisions called meiosis _ and meiosis __. Before meiosis I the cell _________ its chromosomes. The cell divides now similar to mitosis. Each chromosome lines up individually in the center.

31. 31 In ________ of meiosis I, each chromosomes pairs with its corresponding chromosome to form a structure called a ______. As homologous chromosomes pair up and form tetrads, they exchange portions of their chromatids in a process called _________ __ _____.

32. 32 The homologous chromosomes now separate and form ___ new cells. Because each pair of homologous chromosomes was separated, neither of the daughter cells has the ___ complete sets of chromosomes that it would have in a ________ cell. The two cells produced by meiosis I have sets of chromosomes and alleles that are different from each other and from the diploid cell that entered into meiosis I.

33. 33 The two cells produced by meiosis I now enter into meiosis II. The chromosomes are ____replicated before going into meiosis II. During _________ of meiosis II the chromosomes line up in the center of the cell. In ________ of meiosis II the paired chromatids separate. _____daughter cell are produced that are _______ (__).

34. 34 In male animals, the haploid _______ produced by meiosis are called ______. In some plants, pollen grains contain haploid sperm cells. In female animals, generally only ___ of the cells produced by meiosis is involved in reproduction. This female ______ is called an ___ in animals and an egg cell in some plants.

35. 35 Some cell divisions at the end of meiosis I and meiosis II are uneven in some female animals. The cell that becomes an ___ receives more of the _________ than the other three. Those three are known as _____ _____and usually do not participate in reproduction.

36. 36 Mitosis results in the production of two genetically identical diploid (2N)cells, whereas meiosis produces four genetically different haploid (N) cells.

37. 37 LINKAGE AND GENE MAPS OBJECTIVES: 11.5 Identify the structures that actually assort independently. Explain how gene maps are produced.

38. 38 Thomas Hunt Morgan realized that chromosomes are actually a group of linked genes. Chromosomes assort independently and not individual genes.

39. 39 Alfred Strutevant hypothesized that crossing-over was more likely to be separated by a crossover, the farther apart the two genes were. Strutevant came up with a way to map genes. A ____ ___ shows the ________ location of a known gene on a chromosomes.