Chapter Menu Lesson 1:The Cell Cycle and Cell DivisionThe Cell Cycle and Cell Division Lesson 2:Levels of OrganizationLevels 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

Cell Cycle The Cell Cycle Life cycle of cells 2.1 The Cell Cycle and Cell Division phasesIncludes phases of growth, development, and reproduction (interphase, mitosis, and cytokinesis)

Phases of the Cell Cycle interphaseThe phase of the cell cycle when a cell is preparing to reproduce is called interphase. 2.1 The Cell Cycle and Cell Division mitoticThe phase when a eukaryotic cell reproduces is called mitotic 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 functionsCell performs specific functions 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 G The Cell Cycle and Cell Division G1G1: cell grows and carries out its usual cellular functions reproduce –Some cells remain in G1 and do not reproduce, such as muscle cells, red blood cells, and some nerve cells.

Phases of Interphase (cont.) homologousS phase: the homologous chromosomes in a cell’s nucleus continue growth but also replicate 2.1 The Cell Cycle and Cell Division Sister chromatid identicalSister chromatid: copy of chromosome ensures that the new cell is identical

Phases of Interphase (cont.) G2 organellesG2 phase: continues growth and replication but also replicates organelles 2.1 The Cell Cycle and Cell Division Mitochondria and chloroplasts: have own DNA and can duplicate themselves

Mitosis 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. many-celled –Also produce most cells in a many-celled organism. Mitosis

spermeggA different type of cell division produces sperm and egg cells. 2.1 The Cell Cycle and Cell Division fourThere are four 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 cytokinesis daughter cellsDuring cytokinesis the final stage of cell division, the cytoplasm and its components divide to form two identical daughter cells. pinches –At the start of cytokinesis, the cell membrane pinches inward. cell plateA disc, or cell plate, forms between the two new nuclei that are dividing. membrane –This becomes the cell membrane, 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. two numberThe chromosomes of two daughter cells are identical in number and type to each other and to the parent cell. eggAll the cells in the body have identical chromosomes except sperm and 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? AS phase Bprophase Cinterphase Dmitosis 2.1 The Cell Cycle and Cell Division 1.A 2.B 3.C 4.D

Lesson 1 Review In which phase does the nucleus divide? AG2 Bmitosis Ccytokinesis Dcell division 2.1 The Cell Cycle and Cell Division 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? Aplant cell Banimal cell Cstomach cell Dparent cell 2.1 The Cell Cycle and Cell Division 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? Anucleus Bchloroplast Csmooth ER Dspecialized membranes 2.2 Levels of Organization 1.A 2.B 3.C 4.D

Lesson 2 Review What are undifferentiated cells called? Astem cells Btissues Cprokaryotes Dliver cells 2.2 Levels of Organization 1.A 2.B 3.C 4.D

Lesson 2 Review What organ system produces hormones that control body functions? Askeletal Blymphatic Cnervous Dendocrine 2.2 Levels of Organization 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? Asister chromosomes Bhomologous chromosomes Cdaughter chromosomes Dparent chromosomes Chapter Assessment 1 1.A 2.B 3.C 4.D

Sister chromatids are held together at what region of the chromatids? Athe ends Bthe centromere Cthe cell plate DG1 Chapter Assessment 2 1.A 2.B 3.C 4.D

When do the sister chromatids of each replicated chromosome begin to separate? Aprophase Bmetaphase Canaphase Dtelophase Chapter Assessment 3 1.A 2.B 3.C 4.D

By what process do cells become different types of cells with specialized structures and functions? Acell division Bmitosis Ccell differentiation Dthe cell cycle Chapter Assessment 4 1.A 2.B 3.C 4.D

What does a leaf have in common with a bicep muscle? Aboth perform the same function Bboth are at the same level of organization Cboth are tissues Dboth are eukaryotes Chapter Assessment 5 1.A 2.B 3.C 4.D

What happens during cytokinesis? Athe nucleus divides Bthe cytoplasm divides Cchromosomes are replicated Dgrowth and cellular functions CA Standards Practice 1 SCI 1.e 1.A 2.B 3.C 4.D

What is the first phase of mitosis? Ainterphase BG1 Cprophase Dcell division CA Standards Practice 2 SCI 1.e 1.A 2.B 3.C 4.D

What is the most complex level of organization? Aorganism Borgan system Ccells in eukaryotes Dtissues CA Standards Practice 3 SCI 5.a 1.A 2.B 3.C 4.D

What is a group of cells that work together to perform a function called? Aorgan Borgan system Corganism Dtissue CA Standards Practice 4 SCI 5.a 1.A 2.B 3.C 4.D

What is a stem cell? Aa leaf cell Ba differentiated cell Can undifferentiated cell Da fertilized egg CA Standards Practice 5 SCI 1.f 1.A 2.B 3.C 4.D

Concepts in Motion 1

Concepts in Motion 2

Image Bank

Interactive Table

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