In this wetlands ecosystem, the is/are an important abiotic factor that could limit the underwater organism populations. a) dissolved oxygen b) number of predators c) number of plant species d) migratory bird population

A). dissolved oxygen    

Dissolved oxygen is the abiotic factor. Abiotic factors are the non-living components of the environment which can have an influence on the living organisms. Abiotic factors include soil, water, oxygen, temperature etc.

The underwater organism population gets oxygen from aquatic plants which produce oxygen by the process of photosynthesis. Therefore, oxygen is available in the dissolved state in water called as dissolved oxygen. Respiration by underwater animals and plants , decomposition and other chemical reactions requires oxygen. Utilization of dissolved oxygen by underwater animals can limit the overall concentration of dissolved oxygen which can affect the vital metabolism of underwater animals and therefore can limit their population.

the corpus luteum secretes estrogens and progesterone. the latter hormone causes changes in the uterus that make it more suitable for implantation of the fertilized ovum and the nourishment of the embryo. if the egg is not fertilized, the corpus luteum becomes inactive after 10–14 days, and menstruation occurs.

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