With access to land for plants, a vascular system was needed that provided water and nutrients, and integumentary tissue for protection. The further evolution of plants on land was aimed at differentiating thallus into organs and improving sexual reproduction – reducing the dependence on water. Of no less importance was the appearance of mechanical tissues, ensuring the maintenance of the shape of the body in a less dense in comparison with the aqueous ground-air environment.
For animals that came to land, organs providing: the ability to breathe atmospheric air (trachea systems, pulmonary sacs, lungs), movement (free limbs with their belts) and reproduction (organs providing the possibility of internal fertilization, the appearance of egg shells) were of utmost importance.
Remember: The process of learning a person lasts a lifetime. The value of the same knowledge for different people may be different, it is determined by their individual characteristics and needs. Therefore, knowledge is always needed at any age and position.