Which of these describes lichens and mosses that first colonize a previously barren area?

The answer is; pioneer species

These pioneer species have adaptations such as minute roots that enable them to grow on rocks, with little nutrients, and need no soil. This is why they are able to colonize new barren land. They are able to break down rocks to soil and give an opportunity for higher plants to later colonize the environment after time.  

ans.

gregor john mendel is known for study of inheritance in pea plants. he used garden pea plant for his study, having alternative traits for various characters. he performed cross-breeding in pea plants to check how characters are transmitted between parents to offspring, such as cross between pure tall and pure dwarf plant. mendel studied the inheritance patterns in pea plants for various generations.

thus, the correct answer includes options and f).