31 Years NEET Previous Year Questions: Organisms & Populations - 3 - NEET MCQ

Natality refers to the rate at which new individuals are born. Adaptability refers to the capacity of the organisms to adapt themselves to their environment. 

Population is an aggregation or grouping of individuals of the same species at the same time in a particular area. Species is a grouping of individuals of one or more populations resembling each other in important morphological, anatomical and biochemical characters and can potentially interbreed. Biotic community is an assemblage of interdependent, and ecosystem is a self sufficient and self  regulating segment of nature comprising of a biotic community and its physical environment, both interacting and exchanging materials. The basic level of ecological organisation starts with the individual, the next more complex levels are populations, species, community and then ecosystem.

Sunken stomata is the characteristic feature of xerophytes which help in reducing loss of water from leaf surface. These type of stomata are found in Oleander or Pine.

Stenohaline : Steno meaning narrow and haline meaning salt. A fish cannot handle a wide fluctuation in salt content in water. Many fresh water fish tend to be stenohaline and die in environments of high salinity such as the ocean. Fish living in coastal estuaries and tide pools are often euryhaline (tolerant to changes in salinity) as are many species which have life cycle requiring tolerance to both fresh water and sea water environments such as Salmon.

Mutualism type of interactions are shown in plant roots in mycorrhizal region.

Soil particles size defines its texture. The mineral particles present in soil, vary enosmously in size the  fire fiagments. (consisting of sand, silt and clay particles) and coarse fiagments (gravel, copples and stones). The relative proportion's of sand, silt and clay in a soil is referred as soil texture. Fine textured soil have more of clay particles.
Water holding capacity-Larger soil particles like sand, gravel have large pores. This have high less holding capacity and higher percolotion rate field capacity is the of soil moisture or water content held in soil after excess water has drained away.

High organic matter darkens the colour of soil. This is soil.

Homeostasis is the property of an open system, especially living organisms, to regulate its internal environment to maintain a stable, constant condition, by means of multiple dynamic equilibrium adjustments, controlled by interrelated regulation mechanisms. 

Competition is most severe between the members of a population belonging to same niches.

Symbiosis or mutualism is a mutually beneficial association necessary for the survival of both the partners.