The hypha grows and branches to produce a filamentous network called a mycelium. The mycelium has a high surface-area-to-volume ratio, which allows the fungus to absorb nutrients efficiently. If the hyphae of different mating types meet, they are attracted to each other and fuse, forming a cell with a nucleus from each haploid fungus. A cell with two different nuclei is called a heterokaryotic cell. The nuclei do not fuse, so the cell is designated n + n. A heterokaryotic mycelium forms.
Meiosis is a type of cell division required for sexual reproduction and produces gametes or spores. During Meiosis I, DNA replication occurs and chromosomes line up on the equator as a homologous pair known as chromatids. At the first stage of Meiosis, Prophase I, DNA of individual chromosomes coils more and more tightly, known as DNA condensation. Sister chromatids then attach to specific sites on the nuclear envelope to bring the homologous pair of chromosomes close together. The sister chromatids line up so they can pair up with its corresponding "sister gene" on the homologous chromosome.
Recessive gene shows up if it is homozygote, aa. The main objective of the lab is to observe and predict the hereditary traits in fruit flies and the use of Punnett squares to predict the phenotypic and genotypic ratio of wild type (normal) and mutated flies.
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.
Fruit Flies as a mean of genetic study. BACKGROUND INFORMATION. In Mendelian genetics, one can study how heritable traits are passed from parents to their offspring. It gives us a way to predict the phenotypic and genotypic ratio of offspring. There are two kinds of alleles noticeable in genes: dominant and recessive alleles.
2. Copy the table and match the following terms with their definitions: Gene, traits, chromosome, DNA, Genetics, Asexual reproduction, Meiosis, homozygous, heterozygous, allele, phenotype, genotype Term Definition traits Characteristics passed from parents to offspring chromosomes Thread like structures in the nucleus which carry the genes. allele Alternative forms of a gene Gene A part of a chromosome that carries an instruction homozygous Pure breeding for a characteristic eg: TT for tall DNA Deoxyribonucleic acid Genetics Study of Heredity Phenotype The appearance of an individual Geneotype The alleles an individual has for a particular gene. meiosis Two cell divisions resulting in sex cells that contain half the normal number of chromosomes Asexual Formation of new individuals without the production of reproduction sex cells heterozygoys Hybrid (containing two different alleles) eg: Tt (tall) 3. Answer True or False a) A chromosome is found in the nucleus of a cell.
This complementary base pairing is what makes DNA a suitable molecule for carrying our genetic information—one strand of DNA can act as a template to direct the synthesis of a complementary strand. In this way, the information in a DNA sequence is readily copied and passed on to the next generation of cells. Because of the strict order of the chemical pairing, the double helix design facilitates the correct bonding of the appropriate chemical bases. However, some scientists suggest that the double helix design may also help to increase the physical strength of the gene. Gene construction is anti-parallel, meaning the strands run in opposite directions.
Over evolutionary time, they and their DNA became integrated into the cell to form a new type of life called eukaryotes. Endosymbiosis suggests that certain organelles were once free living organisms that were taken into larger cells and the arrangement was beneficial to both organisms. First off, mitochondria and chloroplasts are similar in size and morphology to bacterial prokaryotic cells, though the mitochondria of some organisms are known to be morphologically variable. Also, mitochondria and chloroplasts divide by binary fission, just as bacteria do, and not by mitosis as eukaryotes do. Additionally, the DNA of mitochondria and chloroplasts are different from that of the eukaryotic cell in which they are found.
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
Sexual reproduction, as with other organisms, involves the fusion of two nuclei when two sex cells unite. This joining produces spores that can grow into new organisms. Reproduction of Fungi Asexual spores—microscopic in size—are the common means of reproduction and the primary agents of fungal dispersal. Asexual spores usually germinate and produce new hyphae whenever and wherever moisture is available. Most fungi reproduce asexually.