Step 4: Simulate the Cross in Step 3 Repeat step 2, except for two mice that are heterozygous for fur color and eye color (BbEe). If you simulate breeding using cards and sticks, both partners need to make cards and sticks that represent the alleles for a heterozygous mouse (BbEe). Don’t forget to simulate ten offspring. Step 5: (Optional) Combine Data from Step 5 with Classmates Student Guide
This is when one can see the pigment of the eyes and folded wings. In a few hours of the completion of metamorphosis, the fruit flies will get rounder in the abdomen, darker in color and will extend its wings. In about fourteen days fruit flies will reproduce to adults and once adults’ females may start laying eggs within forty-eight hours. It is important to use virgin females for genetic crossing since they can store sperm after one insemination and use it to reproduce multiple times (Woodrow). With genetic crossing one will observe the phenotypic, the physical observation, received from the genotype, genetic make-up of organism.
3), and adult (Fig. 4). At room temperature, a fresh culture of the Drosophila melanogaster will produce new flies in two week: eight days in the egg and larva stages, and six days in the pupal stage. Two days after the flies emerge the female flies are already starting to reproduce. The Drosophila melanogaster is a good type of fruit fly for genetic studies because they are easily cultured, the flies have a great generation time, and D. melanogaster also have good mutant forms.
Drosophila Lab Eric Johnson 11/19/09 Dr. DelliPizzi Genetics Abstract: In this lab the genetics of Drosophila Melanogaster, also known as the common fruit fly, was examined. Several experiments were performed including crossing ebony flies with vestigial, as well as flies with red eyes and white eyes. The data was collected over a period of 2 months of breeding. The F2 generation of flies in each experiment was also bred to discover what kind of crosses it would produce. In order to perform this experiment first virgin flies had to be attained by separating all adults from the stock vials and quickly separating the newly hatched egg larva into male and female containers.
The crossing in the F2 generation of the heterozygous male and heterozygous female produced two heterozygous offspring, one homozygous recessive offspring and one homozygous dominant offspring. Discussion This experiment was conducted by using aldehyde oxidase (AO) to genetically characterize the aldox gene. It was hypothesized that the gene
What do Punnett squares illustrate? (genetic crosses) 6. Is the exchange of chromosome segments between homologous chromosomes during prophase I of meiosis I (crossing over) 7. How many copies of each autosomal gene affect phenotype? (2) 8.
10101 Chapter 3- Sept 22 Lecture Notes: Principles of Genetics • You have 23 pairs of chromosomes • Strands of DNA molecules spiraled around each other • Genes = unit of hereditary transmission • Grouped in pairs along chromosome, one from each parent • thousands of genes in each chromosome • Homozygous = same chromosomes (genes are identical) • Heterozygous =different chromosomes (genes are different) • Recessive trait = homozygous ONLY • Dominant traits= heterozygous • Sex-linked genes • Located exclusively on X or Y chromosome • Construction of genital • Color blindness Neurons & Glia • Neurons • 70-100 billion • Glia • ~10 X as many -Whole central nervous system is made of of; • Cerebral
January 11, 2014 Pgs: 250-257 AP Biology Meiosis and Sexual reproduction 1. Differentiate between haploid and diploid cells. Give one example of each cell. The difference between a haploid and a diploid cell is that a diploid is a cell that has two sets of chromosomes. On the other hand, a haploid cell contains only one set of chromosomes.
Each parent has a gene pair in each cell for each trait studied. The F1 from a cross of two pure lines contains one allele for the dominant phenotype and one for the recessive phenotype. These two alleles comprise the gene pair. One member of the gene pair segregates into a gamete, thus each gamete only carries one member of the gene pair. Gametes unite at random and irrespective of the other gene pairs involved.
10. Describe how the “packaging” of DNA to form a chromosome occurs. How many chromosomes does a human cell have? Why are there chromosome pairs? What are the sex chromosomes for a female?