CELL EXPLORATION WEBQUEST
Every living thing is composed of at least one cell. Bacteria, amoebae, and paramecia are made of one cell and are capable of the activities of life. Organisms made of one cell are unicellular. Most living things are made of more than one cell and are called multicellular. Cells of these organisms function together to accomplish life activities. How many cells do you think make up your body? The human body is made of trillions of cells.
In order to understand how the cell functions in your body, we have to take a look at how your body is organized. Since you are made of matter, and all matter is made of atoms, your body is a collection of atoms. These atoms combined in specific ways to form molecules. Some of the important molecules in your body are proteins, carbohydrates, lipids, salts, water, and nucleic acids. These molecules combined to form the structures that make up a cell. Since each cell is capable of the activities of life, it is the smallest unit of life.
Cells that are similar can function together. These collections of cells are called tissues. Some tissues that you may be familiar with are the muscle tissue that makes up your heart, epithelial tissue that makes up your skin, and connective tissue that holds your body together. Different groups of tissues can be arranged to form organs. Some organs that you may be familiar with are the stomach, intestines, heart, and lungs. For example, the stomach has epithelium to line the outside and inside surfaces for protection and the muscle tissue allows your stomach to squeeze and churn. Groups of organs can work together as an organ system to perform a specific function. The digestive system functions to breakdown and absorb food so that our bodies can use the energy. The pancreas, stomach, intestines, gall bladder, and esophagus are some of the organs that make up the digestive system. There are 13 systems in the human body that function together to produce an organism – YOU!
Cells are very small and you must use a microscope to look at them. Watch this video (click on “start animation”), then look at the size of cells and answer the following questions. To give you an idea about size, the length of a key on the keyboard is about 1 cm.
EUKARYOTIC CELL ORGANELLES
Since the cell is the fundamental unit of life, it must be capable of independent existence. Some of the necessary life activities are communication, metabolism, protection, and waste disposal. In order to carry out these jobs, the cell has different organs inside of it just like your body has organs. These “tiny organs” are called organelles. Different organs have different jobs and they need the proper supplies of ATP (cellular energy), proteins, oxygen, and other nutrients to carry out their jobs.
To understand how the cell carries out its functions, you should know more about the cytoplasm, cell membrane, and organelles. Click on each structure given in the table below to learn more about each cell part. Complete the table by writing a brief description and function for each part.
The things common to all cells are a cell membrane (plasma membrane), cytoplasm, and organelles. Remember that plant cells have three structures that animal cells don’t. Now look at a drawing of a plant cell. (Hold cursor over organelle to identify it.)
COMPLETE THE TABLE BELOW:
Remember that prokaryotic cells are only found in bacteria! They’re simpler than eukaryotic cells. Look at the bacterial cell, and complete the table below:
After you have read about cells, take the cell quiz. Check your answer after you answer each question.