Answer: Leeuwenhoek biggest contribution is to the first tenet of the cell theory.
Explanation: the first tenet of cell theory states that every living being is made of cells and even an organism can be made of just one cell able to reproduce by itself.
Leeuwenhoek observations stablish the existence of microscopic structures alive some with movement. This helped other scientists to determinate this structures were cells that can make vital processes such as feeding, breathing or reproducing which are determinant in biological definition of life.
The cardiovascular transports oxygen, nutrients and glucose.
Answer:
(1) roots, (2) stems, (3) leaves, and (4) flowers
Explanation:
There are sometimes similarities in the embryonic stages of organisms that do not exist in the adult stages.
