Answer:
Explanation:
Duchenne muscular dystrophy acts as a X-linked recessive disease. Which means the gene sits on the X chromosome, and you need two bad copies to show disease (for females) and one bad copy (to show in males).
Now from our knowledge, we know males are XY and females are XX. Males have only one copy of the X chromosome from their mother and one copy of the Y chromosome from their father, thus if they get the mutated version of the gene that causes this disease, they will get the disease. However, if a female has a mutated version of gene on one of the X chromosome, the other X chromosome could have a normal gene and that normal gene would take over and produce a normal phenotype/function.
Since, boys only have one X chromosome, if they get the mutated gene they will get the disease, whereas females have two X chromosome (so even if one copy is bad and the other is good, the good version can take over, however boys don't have this) thus mostly male children are affected by this.
Explanation:
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An ecological pyramid (also trophic pyramid, Eltonian pyramid, energy pyramid, or sometimes food pyramid) is a graphical representation designed to show the biomass or bioproductivity at each trophic level in a given ecosystem.
A pyramid of energy represents how much energy, initially from the sun, is retained or stored in the form of new biomass at each trophic level in an ecosystem. Typically, about 10% of the energy is transferred from one trophic level to the next, thus preventing a large number of trophic levels. Energy pyramids are necessarily upright in healthy ecosystems, that is, there must always be more energy available at a given level of the pyramid to support the energy and biomass requirement of the next trophic level.
A pyramid of energy shows how much energy is retained in the form of new biomass at each trophic level, while a pyramid of biomass shows how much biomass (the amount of living or organic matter present in an organism) is present in the organisms. There is also a pyramid of numbers representing the number of individual organisms at each trophic level. Pyramids of energy are normally upright, but other pyramids can be inverted or take other shapes.
Ecological pyramids begin with producers on the bottom (such as plants) and proceed through the various trophic levels (such as herbivores that eat plants, then carnivores that eat flesh, then omnivores that eat both plants and flesh, and so on). The highest level is the top of the food chain.