1. Chapter 3 Preview Section 1 Exchange with the EnvironmentExchange with the Environment Section 2 Cell EnergyCell Energy Section 3 The Cell CycleThe Cell Cycle The Cell in Action Concept Mapping

2. Chapter 3 Objectives Explain the process of diffusion. Describe how osmosis occurs. Compare passive transport with active transport. Explain how large particles get into and out of cells. Section 1 Exchange with the Environment

3. Chapter 3 What Is Diffusion? Diffusion is the movement of particles from regions of higher density to regions of lower density. Diffusion of Water Osmosis is the diffusion of water through cell membranes. Section 1 Exchange with the Environment

4. Chapter 3 What Is Diffusion?, continued The Cell and Osmosis Osmosis is important to cell functions. In Animal Cells Plasma surrounds red blood cells and is made up of water, salts, sugars, and other particles. Osmosis keeps the concentration of these particles in balance. In Plant Cells When a wilted plant is watered, osmosis makes the plant firm again by moving water from the soil into the cells. Section 1 Exchange with the Environment

5. Chapter 3 Moving Small Particles Passive Transport Passive transport moves small particles in a cell WITHOUT using energy. Active Transport Active transport moves small particles in a cell by using energy. Section 1 Exchange with the Environment

6. Chapter 3 Section 1 Exchange with the Environment

7. Chapter 3 Moving Large Particles Endocytosis Endocytosis is when a large particle is surrounded by a vesicle and brought INTO a cell. Exocytosis Exocytosis is when a large particle is surrounded by a vesicle and taken to the cell membrane to be thrown OUT of a cell. Section 1 Exchange with the Environment

8. Chapter 3 Section 1 Exchange with the Environment

9. Chapter 3 Objectives Describe photosynthesis and cellular respiration. Compare cellular respiration with fermentation. Section 2 Cell Energy

10. Chapter 3 From Sun to Cell Photosynthesis is how plants, algae, and some bacteria use sunlight, carbon dioxide, and water to make food. Chlorophyll Plant cells have molecules that absorb light energy. These molecules are called pigments. Chlorophyll, the main pigment used in photosynthesis, gives plants their green color. Section 2 Cell Energy

11. Chapter 3 From Sun to Cell, continued Section 2 Cell Energy

12. Chapter 3 Spectrum of Light and Plant Pigments Click below to watch the Visual Concept. Visual Concept Section 2 Cell Energy

13. Chapter 3 Getting Energy from Food Cellular Respiration is the process in which cells use oxygen to produce energy from food. During cellular respiration in animals, food (such as glucose) is broken down into carbon dioxide and water, and energy is released. Section 2 Cell Energy

14. Chapter 3 Getting Energy from Food, continued Connection Between Photosynthesis and Respiration During photosynthesis, plant cells take in carbon dioxide and release oxygen. During animal cellular respiration, cells use oxygen to break down glucose and release energy and carbon dioxide. Fermentation When muscles can’t get the oxygen for cellular respiration, they use fermentation to get energy. Fermentation is the breakdown of food without the use of oxygen. Section 2 Cell Energy

15. Chapter 3 Section 2 Cell Energy

16. Chapter 3 Objectives Explain how cells produce more cells. Describe the process of mitosis. Explain how cell division differs in animals and plants. Section 3 The Cell Cycle

17. Chapter 3 The Life of a Cell The cell cycle begins when the cell is formed and ends when the cell divides and forms new cells. Before a cell divides, it must make a copy of its DNA which is organized into structures called chromosomes. Section 3 The Cell Cycle

18. Chapter 3 The Life of a Cell, continued Making More Prokaryotic Cells Cell division in bacteria is called binary fission, which means “splitting into two parts.” Bacteria have a single circular DNA molecule (chromosome). Binary fission results in two cells that each contain one copy of the circle of DNA. Section 3 The Cell Cycle

19. Chapter 3 The Life of a Cell, continued Eukaryotic Cells and Their DNA The chromosomes of eukaryotic cells contain more DNA than those of prokaryotic cells. In a eukaryotic cell, chromosomes are found in the nucleus and are made of DNA and protein. Pairs of similar chromosomes are called homologous chromosomes. Section 3 The Cell Cycle

20. Chapter 3 The Life of a Cell, continued Making More Eukaryotic Cells The cell cycle has three stages: 1. Interphase: The cell grows and copies its chromosomes. The two copies are now called chromatids. 2. Mitosis: The chromatids separate. 3. The cell splits into two identical cells. Section 3 The Cell Cycle

21. Chapter 3 Mitosis and the Cell Cycle Mitosis has four phases: 1.prophase 2.metaphase 3.anaphase 4.telophase Section 3 The Cell Cycle

22. Chapter 3 Mitosis Click below to watch the Visual Concept. Visual Concept Section 3 The Cell Cycle

23. Chapter 3 Mitosis and the Cell Cycle, continued Cytokinesis is the division of cytoplasm. In animal cells and other eukaryotes that do not have cell walls, division of the cytoplasm begins at the cell membrane. In plant cells and in other eukaryotes with cell walls, a cell plate forms and the cell splits into two cells. Section 3 The Cell Cycle

24. Chapter 3 Section 3 The Cell Cycle