Mitosis is used for almost all of your body’s cell division needs. It adds new cells during development and replaces old and worn-out cells throughout your life. The goal of mitosis is to produce daughter cells that are genetically identical to their mothers, with not a single chromosome more or less. Meiosis, on the other hand, is used for just one purpose in the human body: the production of gametes—sex cells, or sperm and eggs. Its goal is to make daughter cells with exactly half as many chromosomes as the starting cell. To put that another way, meiosis in humans is a division process that takes us from a diploid cell—one with two sets of chromosomes—to haploid cells—ones with a single set of chromosomes. In humans, the haploid cells made in meiosis are sperm and eggs. When a sperm and an egg join in fertilization, the two haploid sets of chromosomes from a complete diploid set: a new genome.In many ways, meiosis is a lot like mitosis. The cell goes through similar stages and uses similar strategies to organize and separate chromosomes. In meiosis, however, the cell has a more complex task. It still needs to separate sister chromatids (the two halves of a duplicated chromosome), as in mitosis. But it must also separate homologous chromosomes, the similar but nonidentical chromosome pairs an organism receives from its two parents. These goals are accomplished in meiosis using a two-step division process. Homolog pairs separate during the first round of cell division, called meiosis I. Sister chromatids separate during a second round, called meiosis II. Since cell division occurs twice during meiosis, one starting cell can produce four gametes (eggs or sperm). In each round of division, cells go through four stages: prophase, metaphase, anaphase, and telophase.Before entering meiosis I, a cell must first go through interphase. As in mitosis, the cell grows during G_1 1 start subscript, 1, end subscript phase, copies all of its chromosomes during S phase and prepares for the division during G_2 2 start subscript, 2, end subscript phase. During prophase, I, differences from mitosis begin to appear. As in mitosis, the chromosomes begin to condense, but in meiosis I, they also pair up. Each chromosome carefully aligns with its homolog partner so that the two match up at corresponding positions along their full length. For instance, in the image below, the letters A, B, and C represent genes found at particular spots on the chromosome, with capital and lowercase letters for different forms, or alleles, of each gene. The DNA is broken at the same spot on each homologue—here, between genes B and C—and reconnected in a criss-cross pattern so that the homologs exchange part of their DNA.This process, in which homologous chromosomes trade parts, is called crossing over. It's helped along by a protein structure called the synaptonemal complex that holds the homologues together. The chromosomes would actually be positioned one on top of the other—as in the image below—throughout crossing over; they're only shown side-by-side in the image above so that it's easier to see the exchange of genetic material.
Answer:
Where did the data come from.
Explanation:
The source of the data is very important, even if the data isnt necessarily false information, its important to make sure the source is credible and their test was set up correctly so the data can be valid.
Like no one knows that whatever
Answer:
A plant takes in carbon dioxide ( CO2 ) and water ( H2O ) and comes out with oxygen ( O2 ) and sugar/glucose ( C6H12O6 ). But Whats the science behind it all?
Explanation:
Once we humans breath out carbon dioxide, the plants open the pores in their leaves to take it in and to obtain water, the plants absorb water and nutrients through the xylem: a tissue made up of thin tubes located just below the surface of the plant's stems. The molecules in this tissue attract water molecules from the soil, so that the water is pulled upwards. This process is called capillary action. Some bacteria and some protistans use the energy from sunlight to produce glucose from carbon dioxide and water. This glucose can be converted into pyruvate which releases adenosine triphosphate (ATP) by cellular respiration. The green leaves of plants carry out both photosynthesis (in light) and respiration (all the time). Photosynthesis uses carbon dioxide to make sugar and produces oxygen as a byproduct. Respiration uses oxygen to release energy from stored sugar and produces carbon dioxide as a byproduct.
Answer – C. (photosynthesis in plants)
Out of the four options given, the only process which produces oxygen is photosynthesis in plants. The other three processes given in the options: Combustion, Respiration in animals, and operation of an acetylene torch normally consume oxygen.
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