Botany MCQs for NEET — Practice Questions with Answers

Biochemical oxygen demand (BOD) represents the amount of oxygen consumed by bacteria and other microorganisms while they decompose organic matter under aerobic (oxygen is present) conditions at a specified temperature. When you look at water in a lake the one thing you don't see is oxygen.

BOD refers to the biological oxygen demand by the microbes to decompose the organic matter present in the water body. Oxygen enters the water through diffusion and water has the highest potential to hold oxygen. The high temperature, untreated sewage having biotoxins, hazardous waste can reduce the oxygen to an alarming level leading to the hypoxia in fishes, whereafter enduring at the maximum level they die resultantly. This occurs because the untreated sewage is rich in organic matter and microbes utilize the dissolved oxygen for the decomposition.

Trinomial nomenclature

Genus - Species - Subspecies

suffix is a term that is kept after the root word of a word, phyta is used as a suffix, it indicates division.

Two or more species occupying the same or overlapping areas are termed as sympatric. Allopatric species are those that occupy completely separate geographic areas without any overlap.

The scientific term for biological classification categories is called a 'taxon' (plural: taxa). A taxon represents a particular level or rank in the taxonomic hierarchy, such as species, genus, family, order, class, phylum, kingdom, and domain.

The species problem is the set of questions that arises when biologists attempt to define what a species is. Such a definition is called a species concept; there are at least 26 recognized species concepts.