Correct answer: D) From bacteria living in their roots
Nitrogen is an essential plant nutrients, but it is metabolically unavailable to higher plants and animals. It is available to some species of microorganism by biological nitrogen fixation in which nitrogen is converted to ammonia with the help of enzyme dinitrogenase.
The process of breaking apart the two atoms in a nitrogen molecule is called nitrogen fixation. Plant obtain the nitrogen they need from the soil which is already fixed by the bacteria and archae.
Example: <em>Azobacter</em><em>,</em> Nostac
Natural selection affects the scope of the niche of a given species. Moreover, trade-offs are associated with differences in traits that also may affect the niche of a species.
<h3>Natural selection and trade-offs </h3>
Natural selection refers to the differential survival or reproduction of individuals in particular environmental conditions.
The different niches occupied by species are mainly a consequence of differential trade-offs among species, i.e., by differential phenotypic features that generate negative correlations among species.
Grime’s Triangle is based on the associations (trade-off) between adaptation to productivity and/or competition, stressful environments (habitats) and disturbance.
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brainly.com/question/23929271
Elements in the same group in the periodic table have similar chemical properties. This is because their atoms have the same number of electrons in the highest occupied energy level. Group 1 elements are reactive metals called the alkali metals.
Answer:
When the inside of the Earth was liquid, gravity caused the heavier elements nickel and iron to sink to the center. Lighter elements floated to the surface. Over time this process caused the Earth to separate into layers.
Explanation:
