Cell Division: Mitosis & Meiosis
employment-agency.info / /student_view0/chapter2/employment-agency.info . L Explain the relationship between mutation, cell cycle, and Cytokinesis employment-agency.info ://www. employment-agency.info employment-agency.info · http:// employment-agency.info employment-agency.info Compare and contrast the 2 types of cell division in depth while discussing the relationship they have to each other. This will be a.
Carrier proteinBinding site a b Cell membrane Carrier protein with altered shape Phospholipid molecules Transported particle Cellular energy Region of higher concentration Region of lower concentration 27 Animation: Primary Active Transport 27 Please note that due to differing operating systems, some animations will not appear until the presentation is viewed in Presentation Mode Slide Show view. Secondary Active Transport 28 Please note that due to differing operating systems, some animations will not appear until the presentation is viewed in Presentation Mode Slide Show view.
How the Sodium-Potassium Pump Works 30 http: Cell membrane 35 3. The Cell Cycle 35 Series of changes a cell undergoes from the time it forms until the time it divide Stages: G phases — cell grows and synthesizes structures other than DNA S phase — cell replicates DNA 37 Mitosis 37 Produces two daughter cells from an original somatic cell Nucleus divides — karyokinesis Cytoplasm divides — cytokinesis Phases of nuclear division: Prophase — chromosomes form; nuclear envelope disappears Metaphase — chromosomes align midway between centrioles Anaphase — chromosomes separate and move to centrioles Telophase — chromatin forms; nuclear envelope forms 38 Mitosis 38 Telophase and Cytokinesis Nuclear envelopes begin to reassemble around two daughter nuclei.
Division of the cytoplasm into two cells. Anaphase Sister chromatids separate to opposite poles of cell. Events begin which lead to cytokinesis. Metaphase Chromosomes align along equator, or metaphase plate of cell. Prophase Chromosomes condense and become visible. Nuclear envelope and nucleolus disperse. Late Interphase Cell has passed the restriction checkpoint and completed DNA replication, as well as replication of centrioles and mitochondria, and synthesis of extra membrane.
Early Interphase of daughter cells— a time of normal cell growth and function. Mitosis and Cytokinesis 39 http: Control of the Cell Cycle 41 http: Control of Cell Division 42 Cell division capacities vary greatly among cell types Skin and blood cells divide often and continually Neuron cells divide a specific number of times then cease Chromosome tips telomeres that shorten with each mitosis provide a mitotic clock Cells divide to provide a more favorable surface area to volume relationship Growth factors and hormones stimulate cell division Hormones stimulate mitosis of smooth muscle cells in uterus Epidermal growth factor stimulates growth of new skin Tumors are the consequence of a loss of cell cycle control Contact density dependent inhibition 43 Tumors 43 Two types of tumors: Benign — usually remains localized Malignant — invasive and can metastasize; cancerous Two major types of genes cause cancer: Stem and Progenitor Cells 45 Stem cell: Can divide to form two new stem cells Self-renewal Can divide to form a stem cell and a progenitor cell Totipotent — can give rise to every cell type Pluripotent — can give rise to a restricted number of cell types Progenitor cell: Cell Death 48 Apoptosis: Programmed cell death Acts as a protective mechanism Is a continuous process 49 49 Important Points in Chapter 3: Outcomes to be Assessed 3.
State the range of cell numbers and cells sizes in a human body. State the term for cell specialization. A Composite Cell List the three major parts of a composite cell. State the general function of organelles.
Explain how the structure of a cell membrane makes possible its function. Describe each type of organelle, and explain its function. Describe the parts of a cell nucleus and their functions. Spindle fibres begin to form from the pair of centrioles in animal cells that begin to move to opposite poles of the cell.
Animation: Mitosis and Cytokinesis
The nuclear envelope surrounding the nucleus begins to dissolve. The chromosomes are guided by the spindle fibres to line up along the equatorial plate in the cell. One spindle fibre microtubule from each pole is attached to each of the sister chromatids.
This is the longest phase in mitosis lasting about 20 minutes. The sister chromatids separate at the centromere and are pulled toward opposite ends of the cell as the spindle fibres shorten.
This phase is very short lasting only a few minutes. The chromosomes uncoil and become less dense which makes them no longer visible. The spindle fibres begin to break down and the process of cytokinesis begins.
In animal cells the process of cytokinesis is known as cleavage. In plant cells cytokinesis is quite different due to the presence of the cell wall. There is a contractile ring of actin microfilaments and myosin molecules that interact together to cause the ring to contract which deepens the furrow and separates the cell contents.
Topic 1.6 Cell Division Chapter 12 Campbell Reece.
The process is like pulling on the drawstrings of your hoodie! The parent cell is pinched into two separate, identical daughter cells. Once they reach the middle they coalesce and form a cell plate which will develop into the cell membranes of the daughter cells.
The vessicles carry the materials such as pectin and other substances needed for the new cell wall and they collect in the cell plate as it grows. This will develop into the middle lamella that will attach the new cell walls to one another. The cell plate grows until it joins with the membrane surrounding the cell. This separates the cell into two identical daughter cells and a new cell wall forms from the contents of the cell plate and cellulose that has been deposited by each daughter cell.
Cyclin is a regulatory protein that assists in the control of the progression of cells through the cell cycle.
Topic Cell Division Chapter 12 Campbell Reece. - ppt download
Cyclins ensure that each task in the cell cycle is not only performed on time but in the proper order. The next task will not begin until the previous tack has been completed.
The cell contains enzymes known as cyclin- dependent kinases. When the cyclin binds to these enzymes they are activated and will attach phosphate groups to other proteins contained in the cell.
The attachment of the phosphates activates these proteins and they begin to carry out the specific tasks of the cell cycle. Benign tumors Tumors are abnormal groups of cells that develop in the tissues of the body. In benign tumors, the cells adhere to one another and do not invade other tissues or move to other body parts.
Benign tumors do not usually cause much harm. Malignant Tumors When cells in a tumor become detached and move to other parts of the body and develop into secondary tumors these are classified as malignant.