Technology of storage and primary processing of agricultural products
- LABORATORY WORK. Topic: Mixing diduragay and poliduragay
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Biologiya laboratoriya 2021
10- LABORATORY WORK.Topic: Mixing diduragay and poliduragayThe purpose of the work. It consists of studying the inheritance of traits in hybrids in which organisms that differ by two pairs of traits are confused. The essence of the work. Mixing organisms that differ from each other by two pairs of alternative traits is called diduragay mixing . G. Mendel conducted the experiment of mixing diduragay with a pea plant . He confused the pea plant, whose grain color was yellow (gene-A), with a smooth shape (gene V), and whose pea color was green (gen-a), and whose shape was wrinkled (gen-v) pea plant. Before Mendel began to confuse , the parental forms attached great importance to being genetically pure, homozygous. For example, if the yellow smooth-grained (mother) plant is mixed with a green curly-grained (parent) plant, the first-generation F 1 hybrid plants obtained from the mix will all have the same yellow smooth-grained plant. The genotype of the F 1 hybrid is heterozygous for two genes. Yellow, smooth Green, wrinkled AAVV x aavv Gametes AV av F 1 AaVv Yellow, smooth The F 1 plants should be self-pollinated to detect changes in the F 2 hybrid . The genotype of the paternal and maternal forms is the same so they form the same gametes. Meyozning anafaza I , 4 (A, B, A, C) of chromosomes from each other independently distributed, but qutublarga 2 (AV, AV or AV, and each homologous chromosome spreads). In the AaVv hybrid, the meiotic process takes place in two variants. I. At the end of AV av meiosis AV and av gametes anaphase I is formed. II. aV At the end of Av meiosis aV and Av gametes anaphase I is formed. Thus, the digeterozygote AaVv forms 4 different gametes . This is because in meiosis, the independent distribution of chromosomes at the poles results in different combinations of genes . Therefore , Mendel's 3rd law is called the law of independent distribution of traits (genes) . The characters whose genes are on different homologous chromosomes are passed on to offspring independent of each other. Motherhood 4 different gametes of the plant (AV, AV, AV, AV) with the same 4 types of gamete to fertilize result can be added. AaBb x AaBb gametes AB, Ab, aB, ab AB, Ab, aB, ab Table 4
In F 2 hybrids, 4th class plants are formed by phenotype (external signs) . (9: 3: 3: 1). 9/16 yellow smooth grain 3/16 green smooth grain 3/16 yellow wrinkled grain 1/16 green wrinkled grain. To enumerate similar genotypes in the Pennet cell to determine genotype segregation , 9 different genotype class plants in the following ratios are 1-AAVV: 2-AAVv: 2-AaVV: 4-AaBv: 1-AAvv: 2-AAVv: 1-aaVV: 2-aaVv : 1-aavv or 1: 2: 2: 4: 1: 2: 1: 2: 1. An example for solving problems 1. Yellow unripe pea seeds of unknown origin were planted. What can be the color and shape of the plants that grow from this frost ? What if the green uncurled grain is sown? Solution: Since the genotype of the unripe grain is unknown to us, we will first determine what genotypes are formed. It is known from Mendel's experiment that the yellow color of the pea grain is not dominated by recessive genes. In this case, this pea plant produces the following genotypes - AAvv, Aavv. So we will work on this issue in two options. 1-variant AAvv x AAvv Gametes Av Av Duragay AAvv Yellow turned 2-variant Aavv x Aavv Gametes Av, av Av, av Duragay AAvv, Aavv, Aavv, aavv In this variant, 4/3 of the resulting hybrid plants turned yellow and 4/1 turned green. Issues to be solved independently 1. What types of gametes appear in the following genotypes? A) AAVV; b) aaVV; v) AAVv; g) Aavv; d) AaVv; e) Aavv; j) aavv 2. Determine the color and shape of the following genotypes: a) aaVv; b) AaVv; v) AaVV; g) aaVV; d) AAVv. Here the yellow color of the grain of the pea is A and the smoothness V is the dominant, the green color a, the unbending v is the recessive character. 3. In the tomato plant, the red color of the fruit is dominant in relation to the sign - K, yellow - in relation to the sign k, long - N, low - h. Digeterozygous was mixed with a tall plant with red fruit, a low plant with yellow fruit. Determine the genotype and phenotype of F 1 plants? 4. The red color of the fruit of the tomato is determined by the gene - R, yellow - r, normal neck - D, low height - d. There are yellow-fruited, normal and red-fruited, low - growing varieties . How to get homozygous (red fruit, normal and yellow fruit, short stature) forms from them? 5. When the tall (A), rust-resistant (V) plant of wheat was mixed with the short-stemmed (a), rust-resistant (v) plant, the 1st generation hybrids obtained were tall, rust-resistant (AaVv). They were self-pollinated and produced 1112 plants of second generation hybrids. How many of these were stunted rust plants? 6. The dominant "A" gene determines the absence of a spike, the recessive "a" gene determines the spike, the dominant "V" gene determines the red color of the spike, and the recessive "v" gene determines the white color. Determine what genotype and phenotype separation occurs from a plant with genotype AaVv? Download 375.5 Kb. Do'stlaringiz bilan baham: 
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