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It is called Semelparity. From wikipedia: Semelparity and iteroparity refer to the reproductive strategy of an organism. A species is considered semelparous if it is characterized by a single reproductive episode before death, and iteroparous if it is characterized by multiple reproductive cycles over the course of its lifetime. You see semelparity as ...


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The gamete doesn't "choose" one or the other. Both are made and you get two gametes, one for each. Also it's unlikely to be an "exact copy" due to recombination and random or independent assortment. There are also smaller influences on genetic variation, and epigenetics, but at this level of question I think you should focus on those two. Was this ...


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Allow me to start off with a nice picture showing the differences - note female gametes are on the left while male gametes are on the right in my examples: Isogametes For a gamete to be considered an isogamete the other gamete that it meets up with to produce is exactly the same in both size, structure and movement. [2] It is literally trying to find ...


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You may be getting confused with the term Allogamy. Humans most higher animals are allogamous, which means that the ovum from one organism is fertilized by spermatozoa of a different organisms. If you read the term allogametes somewhere, then the reference likely means spermatozoa from one organism of a species and ova from another organism of the same ...


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Great question - I think there are two misconceptions in your question that are interfering with your understanding. First, crossing-over occurring at just the "tips" is just for clarity in textbooks so you can easily follow the different pieces of chromosome. Although crossover events tend to occur at particular sequences, these don't have to be at the ...


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There can be and often is more than one crossover per chromosome in meiosis, but how many crossovers occur can depend on the species, sex, age, environment, and which particular chromosome is involved1,2,3. For example, humans typically show 2-3 crossovers per chromosome, but females often show higher recombination rates than males. However, the structure ...


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Meiosis 2 can not be called mitosis. You correctly recognized there are similarities between Meiosis 2 and mitosis. In other contexts, however, there are further differences. For instance Mitosis usually does not recombine genetic material (https://en.wikipedia.org/wiki/Meiosis), and the molecules that regulate Meiosis 2 and Mitosis are different. Calling "...


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Hmmm what seems to me from your statement; "there will be two cells that will be almost opposites (for each chromosome, if one cell has the mother's chromosome, then the other will have the father's chromosome), except for the parts where crossing-over happened" It seems to me; you're missing something. It would happen if the haploid chromosome number ...


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Lizards of the genus Uta are apparently male heterogametic (XY) (Pennock et al. 1969). The XY system seems to be the most common mode of sex determination in iguanid lizards (Kasahara et al. 1983). Kasahara, Y et al. 1983. Chromosome mechanisms of sex determination, G- and C-band patterns and nucleolus organizer regions in Tropidurus torquatus (Sauria, ...


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