1. Cell Structure and Function
Chapter Introduction
Lesson 1: Cells and Life
Lesson 2: The Cell
Lesson 3: Moving Cellular Material
Lesson 4: Cells and Energy
Chapter Wrap-Up

2. How do the structures and processes of a cell enable it to survive?
Cell Structure and Function
How do the structures and processes of a cell enable it to survive?

3. Cell Structure and Function
Alien Life?
Look at the photo at the beginning of the chapter. You might think this unicellular organism looks like something out of a science-fiction movie. Although it looks scary, the hairlike structures in its mouth enable the organism to survive.
What do you think the hairlike structures do?
How might the shape of the hairlike structures relate to their function?
How do you think the structures and processes of a cell enable it to survive?

4. Cell Structure and Function
How do the structures and processes of a cell enable it to survive?
A cell is made up of structures that provide support and movement; process energy; and transport materials into, within, and out of a cell.

5. Cell Structure and Function
Lesson 1: Cells and Life
The invention of the microscope led to discoveries about cells. In time, scientists used these discoveries to develop the cell theory, which explains how cells and living things are related.
Cells are composed mainly of water, proteins, nucleic acids, lipids, and carbohydrates.

6. 1
Cells and Life
What do you think?

7. 1 Cells and Life Do you agree or disagree?
Nonliving things have cells.
Cells are made mostly of water.

8. 1 Cells and Life How did scientists’ understanding of cells develop?
What basic substances make up a cell?

9. 1 Cells and Life cell theory macromolecule nucleic acid protein lipid
carbohydrate

10. 1 Cells and Life Two of a Kind?
Look at the photo at the beginning of the lesson. At first glance, the plant and animal in the photo might seem like they have nothing in common. The plant is rooted in the ground, and the iguana can move quickly. Are they more alike than they appear? How can you find out?

11. 1 Cells and Life Nonliving things have cells.
Do you agree or disagree?
Nonliving things have cells.
Disagree. Cells are found only in living things.

12. 1 Cells and Life Cells are made mostly of water.
Do you agree or disagree?
Cells are made mostly of water.
Agree. Water makes up more than 75 percent of a cell’s volume.

13. 1 Cells and Life How did scientists’ understanding of cells develop?
The invention of the microscope led to discoveries about cells. In time, scientists used these discoveries to develop the cell theory, which explains how cells and living things are related.

14. 1 Cells and Life What basic substances make up a cell?
Cells are composed mainly of water, proteins, nucleic acids, lipids, and carbohydrates.

15. Cell Structure and Function
Lesson 2: The Cell
Cell structures have specific functions, such as supporting a cell, moving a cell, controlling cell activities, processing energy, and transporting molecules.
A prokaryotic cell lacks a nucleus and other membrane-bound organelles, while a eukaryotic cell has a nucleus and other membrane-bound organelles.

16. 2
The Cell
What do you think?

17. 2 The Cell Do you agree or disagree?
Different organisms have cells with different structures.
All cells store genetic information in their nuclei.

18. 2
The Cell
How are prokaryotic cells and eukaryotic cells similar, and how are they different?
What do the structures in a cell do?

19. 2 The Cell cell membrane organelle cell wall nucleus cytoplasm
chloroplast
cytoskeleton

20. 2 The Cell Hooked Together?
Look at the photo at the beginning of the lesson. What do you think happens when one of the hooks in the photo above goes through one of the loops? The two sides fasten together. The shapes of the hooks and loops in the hook-and-loop tape are suited to their function—to hold the two pieces together.

21. 2 The Cell Different organisms have cells with different structures.
Do you agree or disagree?
Different organisms have cells with different structures.
Agree. Two cells with two different functions will also have different structures.

22. 2 The Cell All cells store genetic information in their nuclei.
Do you agree or disagree?
All cells store genetic information in their nuclei.
Disagree. Prokaryotic cells do not have nuclei. DNA is located in the cytoplasm.

23. 2
The Cell
How are prokaryotic cells and eukaryotic cells similar, and how are they different?
A prokaryotic cell lacks a nucleus and other membrane-bound organelles, while a eukaryotic cell has a nucleus and other membrane-bound organelles.

24. 2 The Cell What do the structures in a cell do?
Cell structures have specific functions, such as supporting a cell, moving a cell, controlling cell activities, processing energy, and transporting molecules.

25. Cell Structure and Function
Lesson 3: Cellular Material
Materials enter and leave a cell through the cell membrane using passive transport or active transport.
The ratio of surface area to volume limits the size of a cell. In a smaller cell, the high surface-area-to-volume ratio allows materials to move easily to all parts of a cell.

26. 3
Moving Cellular Material
What do you think?

27. 3 Moving Cellular Material Do you agree or disagree?
Diffusion and osmosis are the same process.
Cells with large surface areas can transport more than cells with smaller surface areas.

28. 3 Moving Cellular Material How do materials enter and leave cells?
How does cell size affect the transport of materials?

29. 3 Moving Cellular Material passive transport active transport
diffusion
endocytosis
osmosis
exocytosis
facilitated diffusion

30. 3 Moving Cellular Material Why the Veil?
Look at the photo at the beginning of the lesson. A beekeeper often wears a helmet with a face-covering veil made of mesh. The openings in the mesh are large enough to let air through, yet small enough to keep bees out. In a similar way, some things must be allowed in or out of a cell, while other things must be kept in or out. How do the right things enter or leave a cell?

31. 3 Moving Cellular Material Diffusion and osmosis are the same process.
Do you agree or disagree?
Diffusion and osmosis are the same process.
Disagree. Osmosis is the transport of water, and diffusion is the movement of other substances.

32. 3 Moving Cellular Material
Do you agree or disagree?
Cells with large surface areas can transport more than cells with smaller surface areas.
Agree. To move substances into and out of a cell efficiently, the surface area of a cell must be large compared to its volume.

33. 3 Moving Cellular Material How do materials enter and leave cells?
Materials enter and leave a cell through the cell membrane using passive transport or active transport.

34. 3 Moving Cellular Material
How does cell size affect the transport of materials?
The ratio of surface area to volume limits the size of a cell. In a smaller cell, the high surface-area-to-volume ratio allows materials to move easily to all parts of a cell.

35. Cell Structure and Function
Lesson 4: Cells and Energy
All living cells release energy from food molecules through cellular respiration and/or fermentation.
Some cells make food molecules using light energy through the process of photosynthesis.

36. 4
Cells and Energy
What do you think?

37. 4 Cells and Energy Do you agree or disagree?
ATP is the only form of energy found in cells.
Cellular respiration occurs only in lung cells.

38. 4 Cells and Energy How does a cell obtain energy?
How do some cells make food molecules?

39. 4 Cells and Energy cellular respiration glycolysis fermentation
photosynthesis

40. 4 Cells and Energy Why are there bubbles?
Look at the photo at the beginning of the lesson. Have you ever seen bubbles on a green plant in an aquarium? Where did the bubbles come from? Green plants use light energy and make sugars and oxygen.

41. 4 Cells and Energy ATP is the only form of energy found in cells.
Do you agree or disagree?
ATP is the only form of energy found in cells.
Disagree. Cells store energy in sugars, lipids, and other molecules.

42. 4 Cells and Energy Cellular respiration occurs only in lung cells.
Do you agree or disagree?
Cellular respiration occurs only in lung cells.
Disagree. Cellular respiration occurs in all cells that have mitochondria.

43. 4 Cells and Energy How does a cell obtain energy?
All living cells release energy from food molecules through cellular respiration and/or fermentation.

44. 4 Cells and Energy How do some cells make food molecules?
Some cells make food molecules using light energy through the process of photosynthesis.