1. Biology Mendelian Genetics Study Guide
2. High School Genetics Study Guide
3. Mendelian Genetics Study Guide Answers

Biology Mendelian Genetics Study Guide

What is another term for a heterozygous genotype? The is the physical feature such as round peas that results from a genotype.

How many traits are involved in a monohybrid cross? What type of organism was used in the first genetic studies done by Gregor Mendel?

What is a karyotype? The two genes for a trait represented by capital & lower case letters are called. How many traits are involved in a dihybrid cross?

Which of Mendel’s laws states that the dominant gene in a pair will be expressed? If both alleles are the same, is the genotype homozygous or heterozygous? Write an example. Write an example of a hybrid or heterozygous genotype. The genes for sex-linked traits are only carried on which chromosome? Who is considered to be the 'father of genetics'? A second filial or F2 cross is also called a cross.

High School Genetics Study Guide

The failure of chromosomes to separate during meiosis (egg & sperm formation) is known as. A cross between two pure or homozygous organisms is called what type of cross —– P1, F1, or F2? What genetic disorder results from a sex-linked trait that affects color vision?

The genetic disorder called is known as the 'free bleeders' disease. Having three 21st chromosomes causes the genetic disorder known as.

A person suffering from the genetic disorder called can not digest fats. disease is a genetic disorder where red blood cells carry less oxygen. Work a P1 cross for plant height in peas. Work an F1 cross for plant height in peas. DIRECTIONS: Answer the questions below as completely and as thoroughly as possible. Answer the question in essay form (not outline form), using complete sentences.

You may use diagrams or pictures to supplement your answers, but a diagram or picture alone without appropriate discussion is inadequate. State the two laws of heredity that resulted from Mendel’s work. What happens during meiosis that would allow genes located on the same chromosome to separate independently of one another?

List the steps in Mendel’s experiments on pea plants. Include the P generation, F1 generation, and F2 generation. Write the equation for probability. Distinguish between codominance and incomplete dominance. Give an example of each type of inheritance. Define the terms, dominant and recessive. Relate the events of meiosis to the law of segregation.

Explain the difference between a monohybrid cross and dihybrid cross. Give an example of each. Explain how you would use a Punnett square to predict the probable outcome of a monohybrid cross. Draw a Punnett square to demonstrate your monohybrid cross. Explain the terms genotype and phenotype.

Explain the terms homozygous and heterozygous.

In his work, Mendel took pure-line pea plants and cross-pollinated them with other pure-line pea plants. He called these plants the parent generation. When Mendel crossed pure-line tall plants with pure-line short plants, he discovered that all the plants resulting from this cross were tall. He called this generation the F 1 generation (first filial generation). Next, Mendel crossed the offspring of the F 1 generation tall plants among themselves to produce a new generation called the F 2 generation (second filial generation). Among the plants in this generation, Mendel observed that three-fourths of the plants were tall and one-fourth of the plants were short. Mendel’s laws of genetics Mendel conducted similar experiments with the other pea plant traits.

Over many years, he formulated several principles that are known today as Mendel’s laws of genetics. His laws include the following: 1. Mendel’s law of dominance: When an organism has two different alleles for a trait, one allele dominates. Mendel’s law of segregation: During gamete formation by a diploid organism, the pair of alleles for a particular trait separate, or segregate, during the formation of gametes (as in meiosis). Mendel’s law of independent assortment: The members of a gene pair separate from one another independent of the members of other gene pairs.

(These separations occur in the formation of gametes during meiosis.) Mendelian crosses An advantage of genetics is that scientists can predict the probability of inherited traits in offspring by performing a genetic cross (also called a Mendelian cross). To predict the possibility of an individual trait, several steps are followed. First, a symbol is designated for each allele in the gene pair. The dominant allele is represented by a capital letter and the recessive allele by the corresponding lowercase letter, such as E for free earlobes and e for attached earlobes. For a homozygous dominant individual, the genotype would be EE; for a heterozygous individual, the genotype would be Ee; and for a homozygous recessive individual, the genotype would be ee. The next step in performing a genetic cross is determining the genotypes of the parents and the genotype of the gametes.

A heterozygous male and a heterozygous female to be crossed have the genotypes of Ee and Ee. During meiosis, the allele pairs separate.

Mendelian Genetics Study Guide Answers

A sperm cell contains either an E or an e, while the egg cell also contains either an E or an e. To continue the genetics problem, a Punnett square is used. A Punnett square is a boxed figure used to determine the probability of genotypes and phenotypes in the offspring of a genetic cross. The possible gametes produced by the female are indicated at the top of the square, while the possible gametes produced by the male are indicated at the left side of the square. Figure 9-1 shows the Punnett square for the earlobe example.

Figure 9-1 An example of a Punnett square. Continuing, all of the possible combinations of alleles are considered. This is done by filling in each square with the alleles above it and at its left. This is done as shown in Figure 9-2. From the Punnett square, the phenotype of each possible genotype can be determined.

For example, the offspring having EE, Ee, and Ee will have free earlobes. Only the offspring with the genotype ee will have attached earlobes. Therefore, the ratio of phenotypes is three with free earlobes to one with attached earlobes (3:1).

The ratio of genotypes is 1:2:1 (1 EE: 2 Ee: 1 ee). Figure 9-2 The Punnett square is used to determine the probabilities of the genotypes and phenotypes in the offspring of a genetic cross.