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Butter flies have an X-Y sex determination system that isdifferent from that of flies or humans. Female butterflies may be either XY or X0,while butterflies with two or more X chromosomes are males. This photograph shows a tiger swallowtail gynandromorph, which is half male (left side) and half female (right side). Given that the first division of the Zygote divides the embryo into the future right and left halves of the butterfly, propose a hypothesis that explains how nondisjunction during the first mitosis might have produced this unusual-looking butterfly.
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- Meiosis DrawingIn this assignment you will track and draw the chromosomes of a diploid organism through all the stages of meiosis. Make sure you label the alleles for genes on the chromosomes the whole way through - every chromatid should have labeled alleles. For meiosis, both crossing over and independent assortment can occur. For the purpose of this exercise, assume that there is a single crossover event on the long chromosome between the A and D genes. Only show crossing over after its fully occured. There are no crossover events on the short chromosome. Regarding independent assortment, there are two possible outcomes in meiosis if there are two homologous pairs of chromsomes. Include both independent assortment possibilities - one on the left side and one on the right. Fill in the possible gamete genotypes for each outcome. If you do this correctly you should end up with 8 different types of gametes. Image attached for genotypes and alleles. Give me a full explaination of each of…arrow_forwardIn Human Cell at Difference Stages of MeloSIS Identify the number of chromosomes in a typical human GERM cell during each stage of meiosis. For each stage, choose either 23 or 46 chromosomes. Prophase I [Choose ] [Choose ] 23 Metaphase I 46 Anaphase I [ Choose ] Telophase I [ Choose ] Prophase II Choose ] Metaphase I [Choose] Anaphase II. [Choose ] Telophase II (Choose)arrow_forwardMitosis happens throughout the male life cycle however, meiosis takes place only for a limited period of his life cycle. Select one: True False In a human body, kidney cells have a different DNA from the one present in the lung cells, because type does a different function. Select one: True False Mitochondria in cells of plant seeds break down starch to produce energy in the form of ATP Select one: True False When a red blood cell (RBC) is placed in distilled water it will shrink Select one: True Falsearrow_forward
- In chickens, a key gene involved in sex determination has recently been identified. Called DMRT1, it is located on the Z chromosome and is absent on the W chromosome. Like SRY in humans, it is male determining. Unlike SRY in humans, however, female chickens (ZW) have a single copy while males (ZZ) have two copies of the gene. Nevertheless, it is transcribed only in the developing testis. Working in the laboratory of Andrew Sinclair (a co-discoverer of the human SRY gene), Craig Smith and colleagues were able to “knock down” expression of DMRT1 in ZZ embryos using RNA interference techniques. In such cases, the developing gonads look more like ovaries than testes [Nature 461: 267 (2009)]. What conclusions can you draw about the role that the DMRT1 gene plays in chickens in contrast to the role the SRY gene plays in humans?arrow_forwardIn chickens, a key gene involved in sex determination has recently been identified. Called DMRT1, it is located on the Z chromosome and is absent on the W chromosome. Like SRY in humans, it is male determining. Unlike SRY in humans, however, female chickens (ZW) have a single copy while males (ZZ) have two copies of the gene. Nevertheless, it is transcribed only in the developing testis. Working in the laboratory of Andrew Sinclair (a co-discoverer of the human SRY gene), Craig Smith and colleagues were able to “knock down” expression of DMRT1 in ZZ embryos using RNA interference techniques (see Chapter 18). In such cases, the developing gonads look more like ovaries than testes [Nature 461: 267 (2009)]. What conclusions can you draw about the role that the DMRT1 gene plays in chickens in contrast to the role the SRY gene plays in humans?arrow_forwardYou are an allele on a single uncondensed chromosome in a Yellow fever-carrying mosquito (Aedes aegypti) diploid cell (2n = 6). Demonstrate in as much detail as possible: (1) how you will get to each genetically identical diploid cell of the multicellular offspring. (2) how you will get to the next generation of sexually reproduced progeny.arrow_forward
- The diploid chromosome number for the somatic cells of a frog is 26. What would that number be after three generations if meiosis did not occur before gamete formation.arrow_forwardPlease help me!arrow_forwardDrosophila melanogaster has four pairs of chromosomes. Sperm for this species are formed by a meiotic process in which homologous chromosomes pair and segregate but do no undergo crossing over. How many genetically different kinds of sperm could be produced by a drosophila melanogaster male? 416 256 64 8arrow_forward
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