AP BIOLOGY

Detailed explanation-1: -In biology, cell theory is a scientific theory first formulated in the mid-nineteenth century, that living organisms are made up of cells, that they are the basic structural/organizational unit of all organisms, and that all cells come from pre-existing cells.

Detailed explanation-2: -The classical cell theory was proposed by Theodor Schwann in 1839. There are three parts to this theory. The first part states that all organisms are made of cells. The second part states that cells are the basic units of life.

Detailed explanation-3: -The Cell Theory Is a Unifying Principle of Biology The cell theory states that all biological organisms are composed of cells; cells are the unit of life and all life come from preexisting life. The cell theory is so established today that it forms one of the unifying principles of biology.

Detailed explanation-4: -Cells are considered as basic units of life because the smallest organisms which are considered as “alive” are unicellular organisms, and all other living organisms are consist of cells. Cell are considered the basic unit of life because all life forms are composed of them.

Detailed explanation-5: -A postulated and widely accepted hypothesis of how most life on Earth operates is known as the “cell theory.” The hypothesis states that cells comprise all organisms. Organs, tissues, and organisms are made up of groups of cells. These are the fundamental assumptions of cell theory.