1. Chapter 2 Table of Contents Section 1 Exchange with the Environment
The Cell in Action
Table of Contents
Section 1 Exchange with the Environment
Section 2 Cell Energy
Section 3 The Cell Cycle

2. Chapter 2 What Is Diffusion?
Section 1 Exchange with the Environment
Chapter 2
What Is Diffusion?
Diffusion is the movement of particles from regions of higher density to regions of lower density.
Diffusion of Water The diffusion of water through cell membranes is called osmosis.

3. What Is Diffusion?, continued
Section 1 Exchange with the Environment
Chapter 2
What Is Diffusion?, continued
The Cell and Osmosis Osmosis is important to cell functions.
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.
When a wilted plant is watered, osmosis makes the plant firm again.

4. Moving Small Particles
Section 1 Exchange with the Environment
Chapter 2
Moving Small Particles
Passive Transport The movement of particles across a cell membrane without the use of energy by the cell is called passive transport.
Active Transport A process of transporting particles that requires the cell to use energy is called active transport.

5. Section 1 Exchange with the Environment
Chapter 2

6. Moving Large Particles
Section 1 Exchange with the Environment
Chapter 2
Moving Large Particles
Endocytosis The active-transport process by which a cell surrounds a large particle and encloses the particle in a vesicle to bring the particle into the cell is called endocytosis.
Exocytosis The process in which a cell releases a particle by enclosing the particle in a vesicle that then moves to the cell surface and fuses with the cell membrane is called exocytosis.

7. Section 1 Exchange with the Environment
Chapter 2

8. Chapter 2 From Sun to Cell
Section 2 Cell Energy
Chapter 2
From Sun to Cell
Photosynthesis is the process by which 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.

9. From Sun to Cell, continued
Section 2 Cell Energy
Chapter 2
From Sun to Cell, continued

10. Getting Energy from Food
Section 2 Cell Energy
Chapter 2
Getting Energy from Food
Cellular Respiration During cellular respiration, food (such as glucose) is broken down into carbon dioxide and water, and energy is released.

11. Getting Energy from Food, continued
Section 2 Cell Energy
Chapter 2
Getting Energy from Food, continued
Connection Between Photosynthesis and Respiration During photosynthesis, cells take in carbon dioxide and release oxygen. During 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.

12. Section 2 Cell Energy
Chapter 2

13. Chapter 2 The Life of a Cell
Section 3 The Cell Cycle
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.

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

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

16. Chapter 2 Mitosis Section 3 The Cell Cycle
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Visual Concept

17. Mitosis and the Cell Cycle, continued
Chapter 2
Section 3 The Cell Cycle
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.

18. Section 3 The Cell Cycle
Chapter 2