Chapter 10 Dragonfly

1. Chapter 10 Dragonfly Cell Growth and Division

2. Standards Addressed National • 7 1.e Students know cells divide to increase their numbers through a process of mitosis,which results in two daughter cells with identical sets of chromosomes • 6IIE 7.c Construct appropriate graphs fromdata and develop qualitative statements about the relationships between variables • 6IIE 7.e Recognize whether evidence is consistent with a proposed explanation State • BIIE 1.g Recognize the usefulness and limitations of models and theories as scientific representations of reality.

3. Section 10-1 Cell GrowthKey Concept: What problems does growth cause for cells? I. Limits to cell growth 1. Why do cells divide rather than continue to grow indefinitely? a.The ___________ the cell is the more demands are placed on the cell’s _____ b.Its more difficult to move enough ____________ and ___________ across the cell membrane 2. “DNA Overload”: a. DNA controls_____ __________ ; found in nucleus of eukaryotes b. DNA meets the needs of the cell when the cell is_________, however as the cell increases in size, the DNA cannot meet its needs anymore  “______________ _________” larger DNA nutrients wastes cell function small crisis Information

4. 3. Exchanging Materials:   a. ________, _________, and _______ enter a cell through its cell membrane. b. ________ _________ leave the same way.   c. Rate of this exchange depends on the surface area to volume ratio II. Surface Area to Volume Ratio 1. To obtain the ratio of surface area to volume, __________ the surface area by the volume. Food oxygen water Waste products divide

5. Cell Sizes Surface Area lengthxwidthx6 54 cm2 24 cm2 6 cm2 Volume Lengthxwidthxheight 27cm3 8 cm3 1 cm3 2:1 6:1 3:1 Ratio of surface area to volume

6. Notice that volume _____________ much more rapidly than surface area.  This causes the ______________________ _________________, which is a serious problem for the cell.  As cells get _____ _________ it makes it more difficult to get sufficient amounts of oxygen and nutrients in and waste products out. Question: How does an organism get bigger if the cells that it is made of do not get larger?  Answer: _____________________ increases surface area to volume ratio to decrease large too It grows more cells.

7. III. Division of the Cell 1. Before the cell gets too large it divides into two “_____________” cells 2. The process is called ________ _______________. Cell division solves the problem of cells getting too large by _______________ while __________________ (more small cells instead of one large cell) daughter cell division Increasing size reducing volume

8. 3.Before cell division, the cell ____________, or copies, its entire DNA.   a. This solves the problem of ___________________ because each daughter cell gets a complete set of __________ information 4.Each cell has an increase in ratio of surface area to volume that allows for more efficient __________________ with the environment. replicates information storage genetic exchange of materials

9. 10-2 Cell DivisionKey Concepts: What are the main events of the cell cycle? What are the four phases of mitosis? All cell division must involve the replication of DNA before cell division so the genetic information can be transferred to the daughter cells. In Prokaryotes the rest of cell division is simply to __________________. In Eukaryotes the division is more complex it occurs in two stages: a.Mitosis: ________________________ b.___________: division of the cytoplasm divide the contents division of the nucleus Cytokinesis

10. Unicellular organisms use mitosis and cytokinesis to ________________. This is a type of _______________ reproduction producing two identical daughter cells from ______ identical parent cell. Multicellular organisms use mitosis and cytokinesis to _________________________ ____________________________ reproduce asexual one add new cells to the organism for growth and development

11. I. Chromosomes 1.Chromosomes are composed are ______ and __________ (histones) and carry the genetic information in eukaryotic cells. a.Each species of organism has a _________ ________ of chromosomes. 1.Drosophila melanogaster has ___ chromosomes 2.Humans have ____ chromosomes DNA proteins specific number 8 46

12. b.Chromosome are ____ __________ except during cell division. (known as ___________ when not dividing) c.Replication (copying) of the DNA occurred _______________________ therefore every chromosome is actually two identical “______” chromatids d. Each pair of chromatids is connected to each other at an area called the ___________, usually located near the center of the chromosome. not visible chromatin before cell division sister centromere

13. centromere Sister chromatids http://www.biostudio.com/demo_freeman_dna_coiling.htm

14. I.The Cell Cycle 1.Cell Cycle: the series of events the cell goes through as they ________________ separated by periods of “in-between” time called ___________. 2.During the cell cycle the cell ________, prepares for __________, and divides to form two daughter cells, each of which then __________________________. 3. _______ phases of the cell cycle grow and divide interphase grows division begins the cycle again Four

15. I.Events of the Cell Cycle a.G1 phase: __________, increase in size and ______________ new proteins and organelles. b.S phase: chromosome __________ (synthesis) c.G2 phase: shortest of the phases, organelles and molecules required for ___________ are produced. d.M Phase: _________and ____________ G1, S, and G2 are all taking place during ____________ : the phase between divisions. cell growth synthesize replication cell division cytokinesis mitosis interphase

16. G1 M-phase s G2

17. I.Mitosis a. The mitotic phase can be sub-divided into four phases ______________, _____________,_____________ and _____________ (PMAT). b.Mitosis is strictly _____________ division. c. Mitosis is followed by cytoplasmic division, or ___________, to complete cell division prophase anaphase metaphase telophase nuclear cytokinesis

18. d.Mitosis results in two “daughter cells”, which are ________ to each other, and is used for growth and asexual reproduction. e.The growth and synthesis phases are collectively called interphase (i.e. in between cell division). f. The only source of genetic variation in the cells is via ________________. identical mutations

19. Interphase Stage between division ·This is when the cell is not dividing, but is carrying out its ____________________. ·Chromatin _____ visible ·_____, histones and centrioles all replicated ·Replication of ______________ e.g. mitochondria, occurs in the cytoplasm. ·G1, S and G2 phases are occurring normal cellular functions is not DNA cell organelles

20. Prophase Beginning of mitosis (nuclear division) ·chromosomes ___________ and become ___________. ·Due to DNA replication during interphase, each chromosome consists of two identical sister ______________ connected at the ____________ ·centrioles move to _________ poles of cell (in animal cells) ·Nucleolus ______________ ·Spindle fibers (microtubules) begin to form and ___________ to chromosomes near the centromere ·Phase ends with the breakdown of the _________________ condense visible chromatids centromere opposite disappears attach nuclear envelope

21. centrioles equator split separate opposite

22. disperse Nuclear membrane reform

23. F.Y.I.: Asexual reproduction is the production of offspring from a single parent using mitosis. The offspring are therefore genetically identical to each other and to their “parent”- in other words they are clones. Asexual reproduction is very common in nature, and in addition we humans have developed some new, artificial methods. The Latin terms in vivo (“in life”, i.e. in a living organism) and in vitro (“in glass”, i.e. in a test tube) are often used to describe natural and artificial techniques.

24. Centrioles Centrioles Centromere Nuclear envelope Centrioles Chromatin Chromosomes _______________ (paired chromatids) Daughter Cells Spindle Centrioles Individual Chromosomes Nuclear envelope reforms http://highered.mcgraw-hill.com/sites/0072437316/student_view0/chapter11/animations.html#

25. For Use with Lab: Plant Cell Growth as seen in Onion Root Tip

26. Animal Cell Division in White Fish Blastula

27. cleavage furrow cell plate cell wall

28. Cell plateforming Wall ofparent cell Daughternucleus Cleavagefurrow Cell wall New cell wall Cleavagefurrow Contracting ring ofmicrofilaments Vesicles containingcell wall material Cell plate Daughtercells Daughter cells • V. Cytokinesis: • a. Division of the ________________ • b. End of the ____ _________ • c. Production of two ______________ daughter cells • d. Different in _________ and _________ cells cytoplasm cell cycle identical plants animals

29. 10-3 Regulating the Cell CycleKey Concepts: How is the cell cycle regulated? How are cancer cells different from other cells? ______________ organisms control cell growth and division very carefully (way to increase number of cells and size of organism) F.Y.I. In different cell types the cell cycle can last from hours to years. For example bacterial cells can divide every 20-30 minutes under suitable conditions, skin cells divide about every 12 hours on average, liver cells every 2 years, brain and muscle cells do not divide. Multicellular

30. This provides the _______________ of cells that ________________________. replacement wear out or are broken down

31. Controls on Cell Division: • Cells in a ________________ will continue to divide until they come into ___________ with other cells. • Then the cells ________ _____________ • Cells are ______________ from the center of the dish. • Then the cells _______________ the open space will begin dividing. • Until they have _______ the empty space. • The controls for cell growth and division can be ___________________. • We can see the same thing happen in our __________________. petri dish contact stop dividing removed bordering filled turned on and off own bodies

32. 3. 1. 5. 2. 4. Question: What happens when you cut your finger or break your bone? Answer: The cells bordering the injury will begin dividing to fill in the gap in the tissues that have been torn or broken. This is the process known as healing.

33. II. Cell Cycle Regulators • 1. Scientists wondered what ____________cell division. • 2. Tim Hunt and Mark Kirschner discovered that cells in mitosis contained a protein that when injected into a cell would cause the formation of spindle fibers. • 3. Protein group known as ____________ regulates the cell cycle. • 4. They rise and fall in time with the ________. controlled cyclins cell cycle

34. 5. Cyclins _____________ the timing of the cell cycle in __________cells. • a. Two main groups of protein regulators • b. Internal Regulators: respond to events __________________ . • Ex. Make sure cell doesn’t enter mitosis until chromosomes have all replicated • c. External Regulators: respond to events _________________________. • Ex. Embryonic growth and healing regulate eukaryotic inside the cell outside the cell

35. III. Uncontrolled Cell Growth • Cancer • Cell Growth is so controlled because when it is not controlled things go very, very______. • 2. _________ is a disorder in which some of the body’s own cells lose the ability to control growth. wrong Cancer

36. 3. Cancer cells do not respond to the _____________that regulate the growth of most cells. • 4. When cells divide ___________________ they form masses of cells called __________ that can damage the surrounding tissue. • 5. Cancer cells can break off and _____________ throughout the body disrupting normal activities and causing serious medical problems or even death. signals uncontrollable tumors spread

37. B. Causes of Cancer 1. Smoking ____________ 2. _____________ exposure 3. ______________ 4.____________ defect in gene p53 C. Cancer is a disease of the __________. tobacco Radiation Viral Infection Genetic cell cycle http://hpv.com/hpv-tv-commercial.html

38. Breast Cancer Cell