I just read the article One Giant Step for my beginning biology class which discusses the evolution of plants in two steps. In the first step it goes into how plants evolved from living in the freshwater to living on land with the use of:
the cuticle and cutinized spores: a method of prevention against desiccation and protection for the spores against drying out
stomata: initially just pores on the plant to enable easier gas exchange they eventually developed guard cells around the pores.
vascular system: a method of coping against gravity so nutrients and water could go to all parts of the plant and the plant can grow bigger and eventually a way to help with the structure of the plant.
Some things I’d like to know is if there’s anything different or side fascinations I should know about all of this. Another is the change from simple pores to pores with guard cells which isn’t covered in the article, anything I should know? Anything helps, thanks
1) The early plants have the affinity to a watery habitat, and therefore it would be fatal for these plants to live on land without a good amount of moisture, and as such, plant adaptation produced layers made of cutin (a waxy chemical substance) to prevent the plant spores from drying out and dying out.
3) A "vascular system" physiologically exists in all plants, from the earliest plants to the youngest ones, although not all plants have "real" vascular tissues. The early plants (specifically the bryophytes) were considered to lack vascular tissues, yet they do have representative substitute tissues that served the same purpose like leptoids and hydroids in mosses (these were not considered vascular tissues because they lack some components of the vascular tissues of the more advanced plants).