Question

Explain at least one adaptation that enabled the ancestral green alga of plants to make the move to land and at least five advantages of the new environment that enabled the success of land plants.

Answer 1

Earlier most of the plants originated in water and remained there for several hundred of years with continuous changes resulting in evolution. Evolutionary studies defined various changes and the modification in plant resulting in the adaptations to  various conditions such as their move to the land surface. The aquatic plants adapted themselves in such a way that they could tolerate the dry and arid environment. Many land plants developed structures which can rigidly support them as there was no chance of buoyancy. Also the plants adapted them in the terms of pollen and seed dispersal as now the water water was not available for easy dispersal of these structures. other common adaptations are alteration of generation and formation of sporangia.

some of the advantages of these adaptations are:

• Availability of the sunlight- one can't deny the fact that sunlight was available to water plants also, but the spectrum quality was different. Land plants are more exposed to the sunlight and hence has increased productivity.
• Availability of CO₂- land plants has more availability of CO₂, and also the the exchange of the gases is more easily possible in case of land plants.
• new development features and the adaptation were acquired by plants  in order to make them survive the harsh conditions such as certain thorns , toxins, were developed in order to protect them from animals.
• The loss of the pollen or gametes were minimised - lots of gametes were lost in water plants , but land plant developed certain specific pollination mechanisms to minimise this loss.
• more protection to developing embryo due to harsh land conditions