anatomy and physiology cell reproduction the cell cycle: mitosis
TRANSCRIPT
![Page 1: Anatomy and Physiology Cell Reproduction The Cell Cycle: Mitosis](https://reader035.vdocuments.net/reader035/viewer/2022081506/5697bf751a28abf838c8026b/html5/thumbnails/1.jpg)
Anatomy and Physiology
Cell ReproductionThe Cell Cycle: Mitosis
![Page 2: Anatomy and Physiology Cell Reproduction The Cell Cycle: Mitosis](https://reader035.vdocuments.net/reader035/viewer/2022081506/5697bf751a28abf838c8026b/html5/thumbnails/2.jpg)
The Cell Cycle
•The series of changes that a cell undergoes from the time it forms until the time it divides.
![Page 3: Anatomy and Physiology Cell Reproduction The Cell Cycle: Mitosis](https://reader035.vdocuments.net/reader035/viewer/2022081506/5697bf751a28abf838c8026b/html5/thumbnails/3.jpg)
Interphase
Period between cell divisions when a cell is carrying on its normal functions and is preparing for division.
•Stages of Interphase• G1 - Growth phase - cells grow and
develop, rapid growth and protein synthesis.
• S - Synthesis phase - DNA replication occurs.
• G2 - Growth phase - centrioles replicate, cell prepares for cell division.
![Page 4: Anatomy and Physiology Cell Reproduction The Cell Cycle: Mitosis](https://reader035.vdocuments.net/reader035/viewer/2022081506/5697bf751a28abf838c8026b/html5/thumbnails/4.jpg)
Mitosis
• Division of a somatic cell to form two genetically identical nuclei or daughter cells.
•P.M.A.T• Prophase• Metaphase• Anaphase• Telophase
![Page 5: Anatomy and Physiology Cell Reproduction The Cell Cycle: Mitosis](https://reader035.vdocuments.net/reader035/viewer/2022081506/5697bf751a28abf838c8026b/html5/thumbnails/5.jpg)
Mitosis
• Somatic Cells - body cells, chromosome number is constant.
• Chromosomes exist in pairs. – Ex. We have 23 pairs of chromosomes or 46
chromosomes.
• Called diploid or 2N (two homologous copies of a chromosome)
• Each pair of chromosomes carries the genetic information for the same trait - Homologous.
![Page 6: Anatomy and Physiology Cell Reproduction The Cell Cycle: Mitosis](https://reader035.vdocuments.net/reader035/viewer/2022081506/5697bf751a28abf838c8026b/html5/thumbnails/6.jpg)
Chromosome Structure
• Sister Chromatids– Duplicated
chromosome made in S phase of interphase.
• Centromere– Holds sister
chromatids together.
![Page 7: Anatomy and Physiology Cell Reproduction The Cell Cycle: Mitosis](https://reader035.vdocuments.net/reader035/viewer/2022081506/5697bf751a28abf838c8026b/html5/thumbnails/7.jpg)
Chromatin
Chromatid
Chromosomes
All the DNA/proteins in nucleus … condenses to form chromosomes during Mitosis
Nucleus
Condensed chromatin .. Either 2 sister chromatids or 1 chromatid
Sister chromatid Sister chromatid
![Page 8: Anatomy and Physiology Cell Reproduction The Cell Cycle: Mitosis](https://reader035.vdocuments.net/reader035/viewer/2022081506/5697bf751a28abf838c8026b/html5/thumbnails/8.jpg)
4 Stages of Mitosis: Prophase
– Chromatin in the nucleus condenses to form visible chromosomes.
– Nuclear membrane breaks down.
– Nucleolus disappears.
– Centrioles move to opposite sides of the cell.
– Microtubules form spindle fibers attached to centrioles.
![Page 9: Anatomy and Physiology Cell Reproduction The Cell Cycle: Mitosis](https://reader035.vdocuments.net/reader035/viewer/2022081506/5697bf751a28abf838c8026b/html5/thumbnails/9.jpg)
4 Stages of Mitosis: Metaphase
Chromosomes align in the center of the cells and attach to the spindle fibers by their centromeres.
![Page 10: Anatomy and Physiology Cell Reproduction The Cell Cycle: Mitosis](https://reader035.vdocuments.net/reader035/viewer/2022081506/5697bf751a28abf838c8026b/html5/thumbnails/10.jpg)
4 Stages of Mitosis: Anaphase
• Centromeres separate- sister chromatids move to opposite ends (poles) of the cell.
• The individual sister chromatids are now call individual chromosomes.
![Page 11: Anatomy and Physiology Cell Reproduction The Cell Cycle: Mitosis](https://reader035.vdocuments.net/reader035/viewer/2022081506/5697bf751a28abf838c8026b/html5/thumbnails/11.jpg)
4 Stages of Mitosis: Telophase
– Like prophase in reverse.
– Chromosomes uncoil.
– Nuclear membrane reforms around chromosome set.
– Nucleoli become visible inside nucleus again.
– Spindle fibers break down.
![Page 12: Anatomy and Physiology Cell Reproduction The Cell Cycle: Mitosis](https://reader035.vdocuments.net/reader035/viewer/2022081506/5697bf751a28abf838c8026b/html5/thumbnails/12.jpg)
Cytokinesis: Cytoplasmic Division
• Considered a separate stage.
• Cell membrane pinches in on itself until 2 daughter cells are formed.
Cytokinesis
![Page 13: Anatomy and Physiology Cell Reproduction The Cell Cycle: Mitosis](https://reader035.vdocuments.net/reader035/viewer/2022081506/5697bf751a28abf838c8026b/html5/thumbnails/13.jpg)
• Regulation
• Internal and external factors regulate cell division.
• Cancer is the uncontrolled growth and division of cells.
• Cancer cells can kill an organism by crowding out normal cells, resulting in the loss of tissue function.
![Page 14: Anatomy and Physiology Cell Reproduction The Cell Cycle: Mitosis](https://reader035.vdocuments.net/reader035/viewer/2022081506/5697bf751a28abf838c8026b/html5/thumbnails/14.jpg)
Cancer
cancer cellbloodstreamnormal cell
Benign Malignant
metastasize
![Page 15: Anatomy and Physiology Cell Reproduction The Cell Cycle: Mitosis](https://reader035.vdocuments.net/reader035/viewer/2022081506/5697bf751a28abf838c8026b/html5/thumbnails/15.jpg)
• Causes of Cancer
• Internal Factors– Inheritance– Mutations
• External Factors» Carcinogens are substances that are known
to produce and promote the development of cancer.
– Radiation– Chemical– Viruses
Skin Cancer
![Page 16: Anatomy and Physiology Cell Reproduction The Cell Cycle: Mitosis](https://reader035.vdocuments.net/reader035/viewer/2022081506/5697bf751a28abf838c8026b/html5/thumbnails/16.jpg)
Mitosis
Review
![Page 17: Anatomy and Physiology Cell Reproduction The Cell Cycle: Mitosis](https://reader035.vdocuments.net/reader035/viewer/2022081506/5697bf751a28abf838c8026b/html5/thumbnails/17.jpg)
![Page 18: Anatomy and Physiology Cell Reproduction The Cell Cycle: Mitosis](https://reader035.vdocuments.net/reader035/viewer/2022081506/5697bf751a28abf838c8026b/html5/thumbnails/18.jpg)
Cell Differentiation
• The process by which cells develop different structures and specialized functions.
• Controlled by the activation of certain genes.
![Page 19: Anatomy and Physiology Cell Reproduction The Cell Cycle: Mitosis](https://reader035.vdocuments.net/reader035/viewer/2022081506/5697bf751a28abf838c8026b/html5/thumbnails/19.jpg)
Stem Cells
A precursor cell that can be triggered by genes to become any type of cell.
![Page 20: Anatomy and Physiology Cell Reproduction The Cell Cycle: Mitosis](https://reader035.vdocuments.net/reader035/viewer/2022081506/5697bf751a28abf838c8026b/html5/thumbnails/20.jpg)
Meiosis
Why does it take place?
•Forming of gametes which are haploid cells
Where does it take place?
•Reproductive organs – Male = testesFemale = ovaries
![Page 21: Anatomy and Physiology Cell Reproduction The Cell Cycle: Mitosis](https://reader035.vdocuments.net/reader035/viewer/2022081506/5697bf751a28abf838c8026b/html5/thumbnails/21.jpg)
+
fertilization
haploid haploid
46
23
46
46
23
![Page 22: Anatomy and Physiology Cell Reproduction The Cell Cycle: Mitosis](https://reader035.vdocuments.net/reader035/viewer/2022081506/5697bf751a28abf838c8026b/html5/thumbnails/22.jpg)
Meiosis - Formation of Gametes
• Meiosis only occurs during the production of gametes.
• After fertilization, the diploid zygote divides by mitosis producing a multicellular, diploid organism.
![Page 23: Anatomy and Physiology Cell Reproduction The Cell Cycle: Mitosis](https://reader035.vdocuments.net/reader035/viewer/2022081506/5697bf751a28abf838c8026b/html5/thumbnails/23.jpg)
Meiosis
• Meiosis reduces the chromosome number from diploid to haploid.
• Occurs in two divisions, called meiosis I and meiosis II.
• Divisions result in 4 daughter cells, each with half the number of chromosomes as the parent. (Haploid = n)
• Meiosis 1 separates the homologous chromosomes (2 copies of each chromosome-1 from mom & 1 from dad) and Meiosis 2 separates sister chromatids.
![Page 24: Anatomy and Physiology Cell Reproduction The Cell Cycle: Mitosis](https://reader035.vdocuments.net/reader035/viewer/2022081506/5697bf751a28abf838c8026b/html5/thumbnails/24.jpg)
Karyotype of a FemaleHomologous chromosomes
![Page 25: Anatomy and Physiology Cell Reproduction The Cell Cycle: Mitosis](https://reader035.vdocuments.net/reader035/viewer/2022081506/5697bf751a28abf838c8026b/html5/thumbnails/25.jpg)
Two Meiotic Divisions
![Page 26: Anatomy and Physiology Cell Reproduction The Cell Cycle: Mitosis](https://reader035.vdocuments.net/reader035/viewer/2022081506/5697bf751a28abf838c8026b/html5/thumbnails/26.jpg)
Meiosis I
![Page 27: Anatomy and Physiology Cell Reproduction The Cell Cycle: Mitosis](https://reader035.vdocuments.net/reader035/viewer/2022081506/5697bf751a28abf838c8026b/html5/thumbnails/27.jpg)
Meiosis II
![Page 28: Anatomy and Physiology Cell Reproduction The Cell Cycle: Mitosis](https://reader035.vdocuments.net/reader035/viewer/2022081506/5697bf751a28abf838c8026b/html5/thumbnails/28.jpg)
Comparing Mitosis and Meiosis
![Page 29: Anatomy and Physiology Cell Reproduction The Cell Cycle: Mitosis](https://reader035.vdocuments.net/reader035/viewer/2022081506/5697bf751a28abf838c8026b/html5/thumbnails/29.jpg)
Formation of Sperm vs. Formation of Eggs
4 haploid gametes … 4 spermProcess = Spermatogenesis 4 haploid gametes …
1 Ovum (egg) & 3 Polar BodiesProcess = Oogenesis