Presentation is loading. Please wait.

Presentation is loading. Please wait.

Cell Features Section 3.2. The Cell Theory The Cell Theory has three parts: 1.All living things are made of one or more cells. 2.Cells are the basic units.

Similar presentations


Presentation on theme: "Cell Features Section 3.2. The Cell Theory The Cell Theory has three parts: 1.All living things are made of one or more cells. 2.Cells are the basic units."— Presentation transcript:

1 Cell Features Section 3.2

2 The Cell Theory The Cell Theory has three parts: 1.All living things are made of one or more cells. 2.Cells are the basic units of structure and function in organisms. 3.All cells arise from existing cells.

3 The Cell Theory, continued Cell Size Small cells function more efficiently than large cells. If a cell’s surface area–to-volume ratio is too low, substances cannot enter and leave the cell well enough to meet the cell’s needs.

4 The Cell Theory, continued Common Cell Features: outer boundary called the cell membrane interior substance called cytoplasm structural support called the cytoskeleton genetic material in the form of DNA cellular structures that make proteins, called ribosomes

5 Prokaryotes Prokaryotes are single- celled organisms that lack a nucleus and other internal compartments. They have a cell wall, may have cilia or flagella, and have a single circular molecule of DNA. Bacteria are prokaryotes

6 Eukaryotic Cells Eukaryotes have: A nucleus which contains the cell’s DNA Other internal compartments called organelles. Animals are eukaryotes

7 Eukaryotic Cells, continued The cytoskeleton provides the framework of a cell. There are three basic kinds of fibers: 1.Microfilaments: long slender filaments made of the protein actin 2.Microtubules: hollow tubes made of the protein tubulin. 3.Intermediate fibers: thick ropes made of protein.

8 Eukaryotic Cells, continued The cytoskeleton’s network of protein fibers anchors the cell’s organelles and other components of the cytoplasm.

9 The Cell Membrane The cell membrane is a selectively permeable barrier that determines which substances enter and leave the cell. This is caused by the way phospholipids in the membrane interact with water. A phospholipid is a lipid made of a phosphate group and two fatty acids.

10 The Cell Membrane, continued Cell membranes are made of a phospholipid bilayer

11 The Cell Membrane, continued


Download ppt "Cell Features Section 3.2. The Cell Theory The Cell Theory has three parts: 1.All living things are made of one or more cells. 2.Cells are the basic units."

Similar presentations


Ads by Google