Embed Size (px)
Citation preview
Chapter Menu
Lesson 1:The Cell Cycle and Cell Division
Lesson 2: Levels of Organization
Click on a hyperlink to view the corresponding lesson.
cell cycle
interphase
centromere
mitosis
cytokinesis
prophase
metaphase
2.1 The Cell Cycle and Cell Division
anaphase
telophase
daughter cell
cell plate
homologous chromosome
sister chromatid
The Cell CycleCell Cycle
• Life cycle of cells
2.1 The Cell Cycle and Cell Division
• Includes phasesphases of growth, development, and reproduction (interphase, mitosis, and cytokinesis)
Phases of the Cell Cycle
• The phase of the cell cycle when a cell is preparing to reproduce is called interphaseinterphase.
2.1 The Cell Cycle and Cell Division
• The phase when a eukaryotic cell reproduces is called mitoticmitotic phase.
Phases of the Cell Cycle (cont.)
2.1 The Cell Cycle and Cell Division
Length of a Cell Cycle
• LengthLength of time for cell cycle is different for different types of organisms and cells
2.1 The Cell Cycle and Cell Division
• 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
Characteristics of Interphase
• Cell performs specific functionsfunctions during interphase.
2.1 The Cell Cycle and Cell Division
– Stomach cells might produce substances that aid in digestion.
– Plant cells might perform cellular respiration.
Characteristics of Interphase (cont.)
• During interphase, the chromosomes in a nucleus are so thin they cannot be observed with a light microscope.
2.1 The Cell Cycle and Cell Division
• 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.
Phases of Interphase
• There are three phases—G1, S, and G2.
2.1 The Cell Cycle and Cell Division
• G1G1: cell grows and carries out its usual cellular functions
– Some cells remain in G1 and do not reproducereproduce, such as muscle cells, red blood cells, and some nerve cells.
Phases of Interphase (cont.)
• S phase: the homologoushomologous chromosomes in a cell’s nucleus continue growth but also replicate
2.1 The Cell Cycle and Cell Division
• Sister chromatidSister chromatid: copy of chromosome ensures that the new cell is identicalidentical
Phases of Interphase (cont.)
• G2G2 phase: continues growth and replication but also replicates organellesorganelles
2.1 The Cell Cycle and Cell Division
• Mitochondria and chloroplasts: have own DNA and can duplicate themselves
MitosisMitosis
• Process in which the nucleus divides
• CytokinesisCytokinesis: process in which the cytoplasm divides
2.1 The Cell Cycle and Cell Division
• New cells made by mitosis and cell division will replace old worn-out dead cells.
– Also produce most cells in a many-celledmany-celled organism.
Mitosis
Mitosis• A different type of cell division produces spermsperm and
eggegg cells.
2.1 The Cell Cycle and Cell Division
• There are fourfour phases of mitosis.
Mitosis
Phases of Mitosis• ProphaseProphase: first phase of mitosis in which the DNA twists
into tight coils and the nucleus membrane breaks apart
2.1 The Cell Cycle and Cell Division
• Replicated DNA condenses into chromosomes.
• Nuclear membrane disappears?
Phases of Mitosis (cont.)
• MetaphaseMetaphase: second phase of mitosis in which the replicated chromosomes move to middle of cell and line up end-to-end
2.1 The Cell Cycle and Cell Division
• Chromosomes align at the middle of the cell.
Phases of Mitosis (cont.)
• AnaphaseAnaphase: third phase of mitosis in which the sister chromatids separate and the centromeres divide
2.1 The Cell Cycle and Cell Division
• Centromeres divide.
• Sister chromatids separate.
Phases of Mitosis (cont.)
• TelophaseTelophase: final phase of mitosis in which a new membrane forms around each set of chromosomes
2.1 The Cell Cycle and Cell Division
• Nuclear membranes form.
Dividing the Cell’s Components• During cytokinesiscytokinesis the final stage of cell division, the cytoplasm and its components divide to form
two identical daughter cellsdaughter cells.
– At the start of cytokinesis, the cell membrane pinchespinches inward.
• A disc, or cell platecell plate, forms between the two new nuclei that are dividing.
– This becomes the cell membranemembrane, which builds the new cell walls.
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 twotwo daughter cells are identical in numbernumber and type to each other and to the parent cell.
• All the cells in the body have identical chromosomes except sperm and egg egg cells.
2.1 The Cell Cycle and Cell Division
Lesson 1 Review
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
2.1 The Cell Cycle and Cell Division
0% 0%0%0%
1. A
2. B
3. C
4. D
Lesson 1 Review
In which phase does the nucleus divide?
A G2
B mitosis
C cytokinesis
D cell division
2.1 The Cell Cycle and Cell Division
0% 0%0%0%
1. A
2. B
3. C
4. D
Lesson 1 Review
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
2.1 The Cell Cycle and Cell Division
0% 0%0%0%
1. A
2. B
3. C
4. D
End of Lesson 1
cell differentiation
stem cell
tissue
organ
organ system
2.2 Levels of Organization
Single-Celled Organisms
• Carry out all the functions needed for their survival, including:
• Need to be organized
2.2 Levels of Organization
– obtaining nutrients
– waste removal
– movement
– protection
– reproduction
Prokaryotes
– Still have structures with specific functions
– Same processes that occur in eukaryotic organelles happen along specialized membranes in bacteria
• Single-celled organisms that do not have nuclei or other organelles, such as bacteria
2.2 Levels of Organization
Eukaryotes
– Include amoeba and some fungi
– Are more complex than prokaryotes
– Have a nucleus and membrane-bound organelles
• Protists are single-celled eukaryotes
2.2 Levels of Organization
Eukaryotes (cont.)
– 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
• Single-celled eukaryotes are more complex than cells in multicellular eukaryotes.
2.2 Levels of Organization
Multicellular Organisms
• Multicellular organisms require organization.
2.2 Levels of Organization
• They have many cells and usually have more than one type of cell.
How do animal and plant cells work?
Cell Differentiation
• Process in which cells become different types of cells
2.2 Levels of Organization
• 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
Stem Cells• Cells that can become different types
of cells
2.2 Levels of Organization
Tissues• Groups of similar cells that work together and perform
a function
2.2 Levels of Organization
Tissues (cont.)
2.2 Levels of Organization
Organs• A group of similar tissues that work together to perform
a function
2.2 Levels of Organization
Organs (cont.)
• Human organs include the heart, lungs, brain, and muscles.
2.2 Levels of Organization
• Plant organs have organs, such as leaves, that store nutrients, exchange gases, transport water or nutrients, or perform photosynthesis.
Organ Systems• One or more organs that work together and perform
one or more functions
2.2 Levels of Organization
Human Organ Systems
2.2 Levels of Organization
Organ Systems (cont.)
Human Organ Systems
2.2 Levels of Organization
Organ Systems (cont.)
Human Organ Systems
2.2 Levels of Organization
Organ Systems (cont.)
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.
2.2 Levels of Organization
Organisms (cont.)
2.2 Levels of Organization
Lesson 2 Review
Where do bacteria carry out the processes that occur in the organelles of eukaryotes?
A nucleus
B chloroplast
C smooth ER
D specialized membranes
2.2 Levels of Organization
0% 0%0%0%
1. A
2. B
3. C
4. D
Lesson 2 Review
What are undifferentiated cells called?
A stem cells
B tissues
C prokaryotes
D liver cells
2.2 Levels of Organization
0% 0%0%0%
1. A
2. B
3. C
4. D
Lesson 2 Review
What organ system produces hormones that control body functions?
A skeletal
B lymphatic
C nervous
D endocrine
2.2 Levels of Organization
0% 0%0%0%
1. A
2. B
3. C
4. D
End of Lesson 2
Chapter Resources Menu
Click on a hyperlink to view the corresponding feature.
Chapter Assessment
California Standards Practice
Concepts in Motion
Image Bank
Science Online
Interactive Table
Virtual Lab
BrainPOP
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
0% 0%0%0%
1. A
2. B
3. C
4. 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
0% 0%0%0%
1. A
2. B
3. C
4. D
When do the sister chromatids of each replicated chromosome begin to separate?
A prophase
B metaphase
C anaphase
D telophase
Chapter Assessment 3
0% 0%0%0%
1. A
2. B
3. C
4. 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
0% 0%0%0%
1. A
2. B
3. C
4. D
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
0% 0%0%0%
1. A
2. B
3. C
4. 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
SCI 1.e
0% 0%0%0%
1. A
2. B
3. C
4. D
What is the first phase of mitosis?
A interphase
B G1
C prophase
D cell division
CA Standards Practice 2
SCI 1.e
0% 0%0%0%
1. A
2. B
3. C
4. D
What is the most complex level of organization?
A organism
B organ system
C cells in eukaryotes
D tissues
CA Standards Practice 3
SCI 5.a
0% 0%0%0%
1. A
2. B
3. C
4. 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
SCI 5.a
0% 0%0%0%
1. A
2. B
3. C
4. 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
SCI 1.f
0% 0%0%0%
1. A
2. B
3. C
4. D
Concepts in Motion 1
Concepts in Motion 2
Image Bank
Interactive Table
Interactive Table
Interactive Table
End of Resources
