2. Chapter Menu Lesson 1: The Cell Cycle and Cell Division
Lesson 2: Levels of Organization
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3. 2.1 The Cell Cycle and Cell Division
interphase
centromere
mitosis
cytokinesis
prophase
metaphase
anaphase
telophase
daughter cell
cell plate
homologous chromosome
sister chromatid

4. The Cell Cycle Life cycle of cells
2.1 The Cell Cycle and Cell Division
The Cell Cycle
Life cycle of cells
Includes phases of growth, development, and reproduction

5. Phases of the Cell Cycle
2.1 The Cell Cycle and Cell Division
Phases of the Cell Cycle
The phase of the cell cycle when a cell is preparing to reproduce is called interphase.
The phase when a eukaryotic cell reproduces is called mitotic phase.

6. Phases of the Cell Cycle (cont.)
2.1 The Cell Cycle and Cell Division
Phases of the Cell Cycle (cont.)

7. 2.1 The Cell Cycle and Cell Division
Length of a Cell Cycle
Length of time for cell cycle is different for different types of organisms and cells
During earliest stages of animal growth, cell cycle can repeat quickly
Dependent on the type of organism and type of cell
Cell cycles repeat quickly in early stages of animal growth

8. Characteristics of Interphase
2.1 The Cell Cycle and Cell Division
Characteristics of Interphase
Cell performs specific functions during interphase.
Stomach cells might produce substances that aid in digestion.
Plant cells might perform cellular respiration.

9. Characteristics of Interphase (cont.)
2.1 The Cell Cycle and Cell Division
Characteristics of Interphase (cont.)
During interphase, the chromosomes in a nucleus are so thin they cannot be observed with a light microscope.
For each chromosome in one set of chromosomes, there is a similar chromosome in the other set of chromosomes.
Each pair of similar chromosomes is called a pair of homologous chromosomes.

10. Phases of Interphase There are three phases—G1, S, and G2.
2.1 The Cell Cycle and Cell Division
Phases of Interphase
There are three phases—G1, S, and G2.
G1: cell grows and carries out its usual cellular functions
Some cells remain in G1 and do not reproduce, such as muscle cells, red blood cells, and some nerve cells.

11. Phases of Interphase (cont.)
2.1 The Cell Cycle and Cell Division
Phases of Interphase (cont.)
S phase: the chromosomes in a cell’s nucleus continue growth but also replicate
Sister chromatid: copy of chromosome
Centromere: a region near middle of each chromatid that holds together each sister chromatid

12. Phases of Interphase (cont.)
2.1 The Cell Cycle and Cell Division
Phases of Interphase (cont.)
G2 phase: continues growth and replication but also replicates organelles
Mitochondria and chloroplasts: have own DNA and can duplicate themselves

13. Mitosis Process in which the nucleus divides
2.1 The Cell Cycle and Cell Division
Mitosis
Process in which the nucleus divides
Cytokinesis: process in which the cytoplasm divides
New cells made by mitosis and cell division replace dead cells
Mitosis

14. 2.1 The Cell Cycle and Cell Division
Phases of Mitosis
Prophase: first phase of mitosis in which the DNA twists into tight coils and the nucleus membrane breaks apart
Replicated DNA condenses into chromosomes.
Nuclear membrane disappears?

15. Phases of Mitosis (cont.)
2.1 The Cell Cycle and Cell Division
Phases of Mitosis (cont.)
Metaphase: second phase of mitosis in which the replicated chromosomes move to middle of cell and line up end-to-end
Chromosomes align at the middle of the cell.

16. Phases of Mitosis (cont.)
2.1 The Cell Cycle and Cell Division
Phases of Mitosis (cont.)
Anaphase: third phase of mitosis in which the sister chromatids separate and the centromeres divide
Centromeres divide.
Sister chromatids separate.

17. Phases of Mitosis (cont.)
2.1 The Cell Cycle and Cell Division
Phases of Mitosis (cont.)
Telophase: final phase of mitosis in which a new membrane forms around each set of chromosomes
Nuclear membranes form.

18. Dividing the Cell’s Components
2.1 The Cell Cycle and Cell Division
Dividing the Cell’s Components
During cytokinesis the final stage of cell division, the cytoplasm and its components divide to form two identical daughter cells.
A disc, or cell plate, forms between the two new nuclei that are dividing.

19. Results of Cell Division
2.1 The Cell Cycle and Cell Division
Results of Cell Division
After mitosis and cell division, the original cell—the parent cell—no longer exists.
The chromosomes of daughter cells are identical in number and type to each other and to the parent cell.
All the cells in the body have identical chromosomes except sperm and egg cells.

20. 2.1 The Cell Cycle and Cell DivisionB C D
When a cell is preparing to reproduce, what phase of the cell cycle is it in?
A S phase
B prophase
C interphase
D mitosis
Lesson 1 Review

21. In which phase does the nucleus divide? A G2 B mitosis C cytokinesis
2.1 The Cell Cycle and Cell Division A B C D
In which phase does the nucleus divide?
A G2
B mitosis
C cytokinesis
D cell division
Lesson 1 Review

22. In which type of cell would you expect to see a cell plate form?
2.1 The Cell Cycle and Cell Division A B C D
In which type of cell would you expect to see a cell plate form?
A plant cell
B animal cell
C stomach cell
D parent cell
Lesson 1 Review

23. End of Lesson 1

24. 2.2 Levels of Organization
cell differentiation
stem cell
tissue
organ
organ system

25. Single-Celled Organisms
2.2 Levels of Organization
Single-Celled Organisms
Need to be organized
Carry out all the functions needed for their survival, including:
obtaining nutrients
waste removal
movement
protection
reproduction

26. 2.2 Levels of Organization
Prokaryotes
Single-celled organisms that do not have nuclei or other organelles, such as bacteria
Still have structures with specific functions
Same processes that occur in eukaryotic organelles happen along specialized membranes in bacteria

27. Eukaryotes Protists are single-celled eukaryotes
2.2 Levels of Organization
Eukaryotes
Protists are single-celled eukaryotes
Include amoeba and some fungi
Are more complex than prokaryotes
Have a nucleus and membrane- bound organelles

28. 2.2 Levels of Organization
Eukaryotes (cont.)
Single-celled eukaryotes are more complex than cells in multicellular eukaryotes.
Single-celled: exist alone and must do everything needed for their survival within the single cell
Multicellular eukaryotes: rely on one another and cannot survive alone

29. Multicellular Organisms
2.2 Levels of Organization
Multicellular Organisms
Multicellular organisms require organization.
They have many cells and usually have more than one type of cell.
How do animal and plant cells work?

30. 2.2 Levels of Organization
Cell Differentiation
Process in which cells become different types of cells
Differentiated cells: specialized structures and shapes for specific functions, such as liver cells or brain cells
Once most human cells differentiate, they cannot become any other type of cell.
Cell Specialization

31. Stem Cells Cells that can become different types of cells
2.2 Levels of Organization
Stem Cells
Cells that can become different types of cells

32. 2.2 Levels of Organization
Tissues
Groups of similar cells that work together and perform a function

33. 2.2 Levels of Organization
Tissues (cont.)

34. 2.2 Levels of Organization
Organs
A group of similar tissues that work together to perform a function

35. 2.2 Levels of Organization
Organs (cont.)
Human organs include the heart, lungs, brain, and muscles.
Plant organs have organs, such as leaves, that store nutrients, exchange gases, transport water or nutrients, or perform photosynthesis.

36. 2.2 Levels of Organization
Organ Systems
One or more organs that work together and perform one or more functions
Human Organ Systems
Part A Part B Part C

37. 2.2 Levels of Organization
Organisms
The most complex unit of living things is a multicellular organism.
Multicellular organisms usually have many organ systems.
Each organ system has its own function but is dependent on other organ systems.

38. 2.2 Levels of Organization
Organisms (cont.)

39. D specialized membranes
2.2 Levels of Organization A B C D
Where do bacteria carry out the processes that occur in the organelles of eukaryotes?
A nucleus
B chloroplast
C smooth ER
D specialized membranes
Lesson 2 Review

40. What are undifferentiated cells called? A stem cells B tissues
2.2 Levels of Organization A B C D
What are undifferentiated cells called?
A stem cells
B tissues
C prokaryotes
D liver cells
Lesson 2 Review

41. What organ system produces hormones that control body functions?
2.2 Levels of Organization A B C D
What organ system produces hormones that control body functions?
A skeletal
B lymphatic
C nervous
D endocrine
Lesson 2 Review

42. End of Lesson 2

43. Chapter Resources Menu
Chapter Assessment
California Standards Practice
Concepts in Motion
Image Bank
Science Online
Interactive Table
Virtual Lab
BrainPOP
Click on a hyperlink to view the corresponding feature.

44. B homologous chromosomes C daughter chromosomes D parent chromosomes
Each chromosome in one set of chromosomes has a similar chromosome in the other set of chromosomes. What is a pair of similar chromosomes called?
A sister chromosomes
B homologous chromosomes
C daughter chromosomes
D parent chromosomes
Chapter Assessment 1

45. Sister chromatids are held together at what region of the chromatids? B C D
Sister chromatids are held together at what region of the chromatids?
A the ends
B the centromere
C the cell plate
D G1
Chapter Assessment 2

46. A B C D
When do the sister chromatids of each replicated chromosome begin to separate?
A prophase
B metaphase
C anaphase
D telophase
Chapter Assessment 3

47. C cell differentiation D the cell cycleB C D
By what process do cells become different types of cells with specialized structures and functions?
A cell division
B mitosis
C cell differentiation
D the cell cycle
Chapter Assessment 4

48. What does a leaf have in common with a bicep muscle?
A both perform the same function
B both are at the same level of organization
C both are tissues
D both are eukaryotes
Chapter Assessment 5

49. What happens during cytokinesis? A the nucleus divides
SCI 1.e A B C D
What happens during cytokinesis?
A the nucleus divides
B the cytoplasm divides
C chromosomes are replicated
D growth and cellular functions
CA Standards Practice 1

50. What is the first phase of mitosis? A interphase B G1 C prophase
SCI 1.e A B C D
What is the first phase of mitosis?
A interphase
B G1
C prophase
D cell division
CA Standards Practice 2

51. What is the most complex level of organization? A organism
SCI 5.a A B C D
What is the most complex level of organization?
A organism
B organ system
C cells in eukaryotes
D tissues
CA Standards Practice 3

52. SCI 5.a A B C D
What is a group of cells that work together to perform a function called?
A organ
B organ system
C organism
D tissue
CA Standards Practice 4

53. B a differentiated cell C an undifferentiated cell D a fertilized egg
SCI 1.f A B C D
What is a stem cell?
A a leaf cell
B a differentiated cell
C an undifferentiated cell
D a fertilized egg
CA Standards Practice 5

54. Concepts in Motion 1

55. Concepts in Motion 2

56. Image Bank

57. Interactive Table
Human Organ Systems
Part A Part B Part C

58. End of Resources