cell growth and division
DESCRIPTION
Cell Growth and Division. Cell 1: 0.00002 m. 0.00002 m= 0.02 mm SA= L x W x # of sides 0.02 mm x 0.02 mm x 6 0.0004 x 6 0.0024 mm 2 V=L x W x H 0.02 mm x 0.02 mm x 0.02 mm 0.000008 mm 3 SA:V=0.0024: 0.000008 1:300. Cell 2: 0.001 m. 0.001 m= 1 mm SA= L x W x # of sides - PowerPoint PPT PresentationTRANSCRIPT
Cell Growth and Division
Cell 1: 0.00002 m0.00002 m= 0.02 mmSA= L x W x # of sides
0.02 mm x 0.02 mm x 6 0.0004 x 60.0024 mm2
V=L x W x H0.02 mm x 0.02 mm x 0.02 mm0.000008 mm3
SA:V=0.0024: 0.0000081:300
Cell 2: 0.001 m
0.001 m= 1 mmSA= L x W x # of sides
1 mm x 1 mm x 6 1 x 66 mm2
V=L x W x H1 mm x 1 mm x 1 mm1 mm3
SA:V=6:1
Cell 3: 2.5 cmSA= L x W x # of sides
2.5 cm x 2.5 cm x 6 6.25 x 637.5 cm2
V=L x W x H2.5 x 2.5 x2.515.625 cm3
SA:V= 37.5:15.6252.4:1
Cell 4: 30 cm
SA= L x W x # of sides30 cm x 30 cm x 6 900 x 65400 cm2
V=L x W x H30 x 30 x 3027000 cm3
SA:V= 5400:270001:5
Cell 5: 15 m
SA= L x W x # of sides15 cm x 15 cm x 6 225 x 61350 cm2
V=L x W x H15 cm x 15 cm x 15 cm 3375 cm3
MINILAB
Analysis:1. the ability of a cell to take in
nutrients and get rid of wastes2. More standard sized Cells
Cell Growth
Limits of Cell Growth1. the ability of a cell to take in nutrients and get rid of wastes2. DNA cannot make RNA fast enough to keep up with the cell’s needs
Example 1: cube surface area vs. volumeCells undergo cell division to solve these problems
Cell Growth
Surface area: Length x Width x number of sides
Volume: Length x Width x Height
Surface Area to Volume RatioSurface area : Volume
Quick Activity
1. Cube is 8 cm in diameter, what is the surface area: volume ratio?
2. You have a cuboid with a length of 5 mm, width of 3 mm, and height of 4 mm. What is the surface area: volume ratio?
answers
1. SA:V• SA= 8 x 8 x 6= 384• V=8 x 8 x 8=512• SA:V=384:512 (3:4)
2. SA:V• SA= 5 x 3 x 6= 90• V=5 x 3 x 4=60• SA:V=90:60 (3:2)
Surface Area to Volume Problem
Volume increases much more rapidly than Surface Area it will cause ratio of surface area to volume to decrease
Ex: Small town with two main streets that is growth
Effect of SA: Volume Ratio
Effect of Surface Area to Volume Ratio
Cell Growth
Cell Division: the process whereby the cell divides into two daughter cells
Cell Growth
Rates of cell growthCells can grow very quickly!
Example: E. Coli (a bacterium) can double its volume and divide every 30 minutes.
Cell Growth
Controls on cell growthCells know when to stop, such as when they contact other cells.
Uncontrolled cell growthCancer cells grow and divide until they run out of nutrients.
Cell Division
Two main stages1. Mitosis: the process by which the nucleus of the cell divides into two nuclei, each with the same genetic information as the parent cell.
Cell Division
Two main stages2. Cytokinesis: the process by which the cytoplasm divides, thus forming two distinct cells.
Chromosomes
Chromosomes
Chromosomes contain the genetic information that is passed from one generation to the next.Chromosomes are made of chromatin.
Chromosomes
Chromatin is made of DNA and protein.
Chromosomes
Histones are proteins that help DNA to coil tightly.
Chromosomes
Chromatids: two identical parts of the chromosome.
Centromere: binds chromatids together
Cell Cycle
Cell cycle: the period from the beginning of one mitosis to another.Events of the cell cycle:
1. Interphase2. Mitosis3. Cytokinesis
Cell Cycle
Interphase: period between cell divisions; time of intense activity by the cell.
G1 phase: cell growth and developmentS Phase: DNA replication G2 Phase: shortest; synthesis of organelles and materials
Cell Cycle
Cell Cycle
Mitosis: process by which the nucleus of the cell is divided into two nuclei.
Metaphase
Anaphase
Telophase
Cell Cycle
Prophase:1. Chromosomes appear (chromatin condenses and coils)2. Centrioles separate and move to opposite sides of the nucleus.3. Chromosomes attach to spindle fibers.4. Nucleolus disappears and nuclear envelope breaks down.
Cell Cycle
Metaphase:1. Chromosomes line up across center (equator) of cell.2. Microtubules connect centromeres to poles of spindle.
Cell Cycle
Anaphase:1. Centromeres split; sister chromatids separate.2. Spindle gets longer.3. Chromosomes go to poles.
Cell Cycle
Telophase:1. Chromosomes uncoil into chromatin.2. Nuclear envelope reforms, spindle breaks down, nucleolus becomes visible.
Cell Cycle
Cytokinesis: process by which cytoplasm divides, thus forming two distinct cells.
Pop Quiz
1. What are the 3 events of the cell cycle?
2. What are the stages of interphase?
3. What are the stages of mitosis?
4. What is cytokinesis?
1. What are the 3 events of the cell cycle?1. Interphase, mitosis, & cytokinesis
2. What are the stages of interphase?1. G1, S, & G 2 phase
3. What are the stages of mitosis?1. Prophase, metaphase, anaphase, &
telophase4. What is cytokinesis?
1. The division of the cytoplasm resulting in 2 identical daughter cells
Pop Quiz
1. What happens doing each stage of interphase?
2. What happens doing each phase of mitosis?
3. When do cells stop dividing?