Answer:
organisms that have more favorable traits tend to leave more offspring ... improved fitness of certain individuals in the population that allows for survival and reproduction. ... Based on H-W conditions, five major causes of evolution: ... factors that prevent organisms of two species from producing vigorous, fertile offspring
Explanation:
Molecules are defined as the smallest particles of a chemical compound or an element, and are made up of atoms. Cells are made up of semi permiable membranes that only allow selected materials to move in or out of the cell, therefore due to the big size of molecules compared to atoms the membrane doesn't allow their passage in the cell. Therefore the cell doesn't allow most molecules to diffuse passively to the cell. Secondly, molecules that can enter the cell requires specific carriers carriers that will enable entry of small molecules in the cell.
Plants and animals live in interacting, interwined communities. There is a characteristic set of species in different environments. For example, certain species of trees, shrubs, ground cover, arthropods, reptiles, mammals, birds etc. live in a temperate forest environment. A completely different set of creatures live in a marsh, or a grassland or an agroecosystem. However, the relationships between these groups can be defined by the ecological role they play, the flow of energy between them and the cycling of nutrients between them. This is a fancy way of saying "everything is connected"! And if you change one part of the system, something else changes. In an ecosystem management decision, you hope you know what those consequences of your actions are!) This is important in managing agroecosystems as well.
<span>Any physical or psychological event that produces stress</span>