ESSAY: REPRODUCTIVE STRATEGIES.
Reproduction is fundamental for all known life because it means the continuity of its specie. Every organism is the result of reproduction. As every specie is different from one to another, their reproductive strategies are also different. There are two reproductive strategies used by organisms: Sexual and asexual reproduction. Usually, big and medium-size(multicellular) species are the ones who reproduce sexually and smaller (unicellular) species reproduce asexually. What I’m going to emphasize is these reproductive strategies’ advantages and disadvantages making kind of a comparison of them to explain which might be the most effective strategy for a specie to prolong its continuity.
Sexual reproduction is the process in which 2 involved parentscontribute with one sex cell (femaleegg and malesperm) to create offspring.
During sexual reproduction the sperm reaches the egg fertilizing it; this forms a zygote that contains the complete genetic information of the new organism, which will be genetically different to each parent.
Sexual reproduction is complicated in comparison with asexual reproduction.
For sexual reproduction there areneeded: Two agreeing parents, courtship rituals, the egg’s fertilization, the division by mitosis, outside help and Parental care.
All this requirements may complicate the process and make its duration period significantly longer than the duration period of asexual reproduction. This might seem a disadvantage considering that during asexual reproduction there are produced more offspring takingless time, but I think that over all of these there is an advantage.
After the fertilization occurs the first advantage: crossing-over of chromosomes. This crossing-over gives the offspring a random mix of its parents’ genetic information. This gives the most important of all the advantages: genetic variability. This means diversity of genes’ information; This genetic variability gives everygeneration new traits as modifications in the body’s organism or different behavior which help with adaptions giving a great advantage to sexual reproducers over asexual ones because differing from asexual reproduction, here there are no clones, every single offspring is different to the others.
Then, even if the number of offspring is less in sexual reproduction, it gives an advantage for the parentalcare. Having less offspring to take care of, will be an advantage letting parents give a more dedicated and personalized attention. Parental care helps offspring surviving because of the feeding, training and protection parents provide.
Example: humans are a great example to talk about the sexual reproduction. For humans there are many courtship rituals and finding two parents that agree withthe reproduction process is somehow hard, during the process there are also several outside help needed and in almost all of the cases there is parental care. Humanity is a great example to show our genetic variability. On planet earth there are over 6 billion people that have survived over thousands of years because sexual reproduction has helped humans developing adaptions for example: forliving in cold places, walking straight etc. It has also helped giving our planet a lot of racial diversity. We all have different: behaviors, skin color, hair color, eyes color etc.
Asexual reproduction is the process where the formation of new individuals from the cell(s) of a single parent happens. This means that there is no fusion of gametes (no egg and no sperm).
Kinds of asexualreproduction: binary fission, budding, regeneration, and pathogenesis.
Example: bacteria reproduce by binary fission splitting into two or creating spores. Bacteria cell grows until it doubles its normal size. Like any cell, bacteria are surrounded by a cell membrane. When the bacteria cell doubles in size, this membrane grows down its middle. When this membrane is complete, and stretches from one end...
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