Discuss the Problems That Plants Had to Overcome to Adapt

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The Answer is When plants made the transition from water to land, they had to solve most of the same problems that animals did: desiccation, support, reproduction, and the effects of gravity. Most experts agree that the ancestors of land plants first evolved in a marine environment, then moved into a freshwater environment before finally moving onto land. In this way, the differences in osmotic pressures between saltwater and freshwater were overcome while the plant was still in the water. The development of vascular tissue allowed for the transport of water and nutrients throughout a plant. Vascular tissue also provides some support for the plant body. Additional strength is derived from the organic compounds lignin and cellulose, found throughout a plant's walls. The problem of desiccation was circumvented by the evolution of cutin, an organic compound found in the outer-wall layers of plants. Cutin also provides additional resistance to oxidation, the effects of ultraviolet light, and the entry of parasites. Roots evolved in response to the need to collect water and nutrients from the soil and to help anchor the plant in the ground. The evolution of leaves from tiny outgrowths on the stem or from branch systems provided plants with an efficient light-gathering system for photosynthesis.

Discuss the Problems That Plants Had to Overcome to Adapt

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