BIO 320 EXAM 1

BIO 320 EXAM 1 How do abiotic factors promote or limit the number of species living in a region? - CORRECT REPLY-Light, water, oxygen, and heat are three abiotic factors that influence the amount of life that an area can sustain. Plants and algae require light to make carbohydrates (glucose). The biomass in these photosynthetic organisms supports the survival and reproduction of animals. Fungi and bacteria rely on the biomass of plants and animals as well. Therefore, the abundance of light will limit how many and which species can survive in an area. Additionally, places with little water will prevent many organisms from surviving. Too little or too much heat will prevent organisms from surviving as well, because metabolic reactions require a specific range of temperatures How do interactions between species promote or limit the number of species living in a region? - CORRECT REPLY-Competition usually limits biodiversity. In most cases, competition between species will prevent some species from persisting. In rare cases, however, competition promotes speciation through disruptive selection within populations. Mutualism benefits all species involved, and therefore promotes the persistence of those species. However, mutualism among one group of species can help this group outcompete other species.