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Sexual and Asexual Reproduction

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The process of sexual reproduction occurs by the formation of gametes with a haploid set of chromosomes. During the process of fertilization, these two gametes combine or fuse to form a cell with a diploid set of chromosomes. Sexual reproduction is common in higher organisms like multicellular animals, some fungi, and plants. It is absent in prokaryotes without nuclei but the process of bacterial conjugation, transformation, and transduction are similar in process to sexual reproduction. Sexual reproduction is characterized by the fertilization of a female gamete by a male gamete to form an offspring that is genetically different from both the parents. Sexual reproduction is a bi-parental process which requires two different individuals of different sex. The process of sexual reproduction is more complicated than asexual reproduction and has specialized parts and cells involved in the process. The formation of gametes with half the number of chromosomes is an important aspect of sexual...
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Cellular Reproduction

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  Cellular Reproduction Our cells reproduce so that we can grow and regenerate. For example, cells are constantly doubling so that our nails and hair continue to grow. The process by which a cell divides into two genetically identical copies is called mitosis. To accomplish this, the cell must first make a second copy of all the DNA in its nucleus. The DNA then condenses into rod-like structures known as chromosomes.  Both copies of the chromosomes are glued together in the middle, so they look like an X under the microscope. Once the nuclear membrane is ruptured, the chromosomes line up in an orderly row in the center of the cell. The chromosome pairs then divide and move to opposite poles of the cell before it divides into two genetically identical daughter cells. When the sex cells, the sperm and the egg, are involved, cell division takes place to a completely different level! The process is called meiosis.                   ...
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Mitosis and Meiosis

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Mitosis An average baby is generally not much taller than 50 centimeters after birth. However, over time his height increases, almost at a dizzying rate, until he reaches one meter at the age of four. The same happens with the child's mass, which increases from about 3.5kg at the time of delivery to 16kg when he reaches four years of age. How is it possible? Something must happen in the body of an infant so that, in a matter of just four years, it doubles its height and quintupled its mass. I anticipate that it is not a "engorgement" spell or any type of supernatural ability that only babies possess. What happens to babies at this stage is not different from what happens daily in our bodies: the cells have multiplied, giving rise to new cells. The difference is that, while in children, the process responsible for multiplying our cells acts at a frantic rate, in adults it is reduced. This process is known as "mitosis" which in biology, mitosis is a process that o...
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Did you know

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Bacteria: Diseases caused by bacteria can enter your body when you touch your nose, mouth, eyes, and open wounds. Since we carry between 2 and 10 million bacteria from the elbow to the tips of the fingers.  Viruses: Throughout our lives we spend a whole year in bed because of colds. One year! So it can be said that rhinovirus, the cause of colds, is one of the most 'successful' viruses. Its symptoms are already described in the oldest medical treatise - the so-called Ebers papyrus - written in Egypt 3,500 years ago. In ancient Greece, Hippocrates attributed colds to mood swings, and at the beginning of the last century they thought they were caused by morning walks  Recommendations to return to previous classes: Among the recommendations, the majority of those who participated in the conference entitled Recreating learning in a pandemic, concluded that it is necessary to review the way in which activities are organized within schools and some logistics for the return, as a b...
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