Living Things are Different from Nonliving Things
Any individual form of life that uses energy to carry out its activities is an organism.
Living things have characteristics to grow into adults.
All organisms get water and other materials from the enviroment
All Living Things Are Made Of Cells
Multicellular organisms have a more complex body than unicellular organisms.
Some organisms are made of a single cell. These organisms are unicellular. These organisms are very tiny.
Organisms made of multiple cells are multicellular. These organisms are things that you can see like frogs and other animals.
The Microscope Led to The Discovery of Cells
A microscope is an instrument which makes an object appear bigger than it is
Hooke looked at a cork and a piece of bark from an oak tree. The oak tree bark had small compartments that looked like tiny, empty, rooms, or cells. The cells that Hooke was looking at however were dead.
In 1660, Robert Hooke began using a microscope to look at all sorts of material
Cells come from other cells
Hooke and Leeuwenhoek´s studies made other people question if other living things had cells.
In 1850 people studied all types of living cells learned that cells divide.
Scientists then came up with another question: Where do cells come from?
The cell theory is important to the study of biology
A scientific theory is a widely accepted explanation of things observed in nature
A theory must be supported by evidence, including experimental evidence and observations
Theories are important because they serve as a foundation for further research and study