Mendelian Genetics

Traits get passed down from one generation to the next through Meiosis (cell division), where each parent gives you one Gene for each trait.

parent carried the b allele. The F1 offspring of such a cross would be Bb, and

This Punnet Square represents the F1 offspring breeding with each other to create more offspring. This second set of offspring is the F2 generation. If both parents are heterozygous dominant, then the offspring expected would be: 50% heterozygous dominant, 25% homozygous dominant and 25% homozygous recessive.

A) Describe the essential features of TWO of the procedures/techniques below. For each of the procedures/techniques you describe, explain how its application contributes to understanding genetics.

* How is it possible for an offspring to exhibit a recessive trait if neither parent exhibited that

Apply your understanding of how alleles assort and combine during reproduction to evaluate a scenario involving a monohybrid cross.

with a frequency of 25%, and crossover gametes between genes Y and Z are observed with a

Now you have determined some facts about the grounded allele and the trait that it causes. Given what you know, do you expect the mutant F1 flies to be homozygous or heterozygous for the allele that causes the grounded trait? According to your reasoning, if you mated two mutant F1 flies, what percentage of flies would you expect to be wild type versus mutant in the F2 progeny? Draw a Punnett square of this cross to justify your answer.

This lab had 2 exercises. Exercise 9.1 involved observing pictures of 60 F2 offspring and recording the phenotypes for 6 different traits. Exercise 9.2 required us to perform the “chi-square test” to determine whether the data we collected matches the standard Mendelian ratio.

You are also provided with a heterozygous female, and a homozygous recessive male for a genetic cross. In this particular female, all the dominant alleles are on one chromosome, and the recessive counterparts are on the other homologous chromosome. Due to a chromosomal condition, in the female no recombination occurs between the M and N loci. Normal recombination occurs between the L and M loci. Diagram this cross, and show the genotypes and frequencies of all offspring expected from this cross.

Mendel’s law of independent assortment deals with dihybrid crosses meaning that independent assortment dealt with the crosses in Group 2 (ap+/ap; se+/se x ap+/ap; se+/se) and Group 4 (vg+/vg; se+/se x vg+/vg; se+/se). This is also the law of independent assortment as the cross deals with the production of haploid cells to the offspring (Gen.: Analysis & Principles, p28). Independent assortment is observed in these two crosses as there are to different traits within the

i) (one point) What proportion of gametes produced by the F1 have the dominant allele for both loci? What proportion of the gametes produced by line B have the d

The major topic of this experiment was to examine two different crosses between Drosophila fruit flies and to determine how many flies of each phenotype were produced. Phenotype refers to an individual’s appearance, where as genotype refers to an individual’s genes. The basic law of genetics that was examined in this lab was formulated by a man often times called the “father of genetics,” Gregor Mendel. He determined that individuals have two alternate forms of a gene, referred to as two alleles. An individual can me homozygous dominant (two dominant alleles, AA), homozygous recessive, (two recessive alleles, aa), or heterozygous (one dominant and one recessive

Genes is the physical and functional unit of heredity which are made up of DNA. It carries the information of that determines traits that are passed on by the parents. There are two copies of genes which comes from each parents which is to be exact twenty chromosome from each parent to make up forty six chromosome in a baby. As by the

Offspring differ somewhat from their parents and from one another. Instructions for development are passed from parents to offspring in thousands of discrete genes, each of which is now known to be a segment of a molecule of DNA. This essay will explore some of the reasons behind how and why these differences in appearance arise, from the base sequence of DNA through to the observed phenotype.