what do all cells require to survive? a complete set of genetic instructions – to produce required...
TRANSCRIPT
![Page 1: What do all cells require to survive? A complete set of genetic instructions – to produce required molecules – to direct life processes Genetic instructions](https://reader035.vdocuments.us/reader035/viewer/2022070408/56649e675503460f94b6263b/html5/thumbnails/1.jpg)
![Page 2: What do all cells require to survive? A complete set of genetic instructions – to produce required molecules – to direct life processes Genetic instructions](https://reader035.vdocuments.us/reader035/viewer/2022070408/56649e675503460f94b6263b/html5/thumbnails/2.jpg)
What do all cells require to survive?
• A complete set of genetic instructions
– to produce required molecules
– to direct life processes• Genetic instructions are coded in the DNA of cells
![Page 3: What do all cells require to survive? A complete set of genetic instructions – to produce required molecules – to direct life processes Genetic instructions](https://reader035.vdocuments.us/reader035/viewer/2022070408/56649e675503460f94b6263b/html5/thumbnails/3.jpg)
Why do cells divide?
• Growth
• Repair injuries
• Natural replacement
![Page 4: What do all cells require to survive? A complete set of genetic instructions – to produce required molecules – to direct life processes Genetic instructions](https://reader035.vdocuments.us/reader035/viewer/2022070408/56649e675503460f94b6263b/html5/thumbnails/4.jpg)
The Cell Cycle
• Defined as the activities of a cell from one cell division to the next, during which…
– the cell grows, adding more cytoplasmic constituents
– the DNA is replicated
– the cell divides into two identical daughter cells
![Page 5: What do all cells require to survive? A complete set of genetic instructions – to produce required molecules – to direct life processes Genetic instructions](https://reader035.vdocuments.us/reader035/viewer/2022070408/56649e675503460f94b6263b/html5/thumbnails/5.jpg)
During non-division phase of cell cycle
• DNA molecules in extended, uncondensed form = chromatin
– a cell can only use DNA to produce molecules when in extended state
“chromatin” means colored thread
![Page 6: What do all cells require to survive? A complete set of genetic instructions – to produce required molecules – to direct life processes Genetic instructions](https://reader035.vdocuments.us/reader035/viewer/2022070408/56649e675503460f94b6263b/html5/thumbnails/6.jpg)
During division phase of cell cycle
• DNA molecules condense to form chromosomes prior to division
– easier to sort and organize DNA into daughter cells
![Page 7: What do all cells require to survive? A complete set of genetic instructions – to produce required molecules – to direct life processes Genetic instructions](https://reader035.vdocuments.us/reader035/viewer/2022070408/56649e675503460f94b6263b/html5/thumbnails/7.jpg)
Structure of a chromosome
• unreplicated chromosome
arm armcentromere
“chromosome” means colored body
![Page 8: What do all cells require to survive? A complete set of genetic instructions – to produce required molecules – to direct life processes Genetic instructions](https://reader035.vdocuments.us/reader035/viewer/2022070408/56649e675503460f94b6263b/html5/thumbnails/8.jpg)
Prior to cell division:• chromosomes (DNA) are replicated (duplicated)
duplicatedchromosome
• duplicated chromosome – attached at their centromeres – as long as attached, known as sister chromatids
![Page 9: What do all cells require to survive? A complete set of genetic instructions – to produce required molecules – to direct life processes Genetic instructions](https://reader035.vdocuments.us/reader035/viewer/2022070408/56649e675503460f94b6263b/html5/thumbnails/9.jpg)
Interphase
“I am a cell”•The cell spends a majority of it’s time in this phase. During interphase…
• the cell grows in size• it makes copies of its organelles•It makes copies of its DNA
![Page 10: What do all cells require to survive? A complete set of genetic instructions – to produce required molecules – to direct life processes Genetic instructions](https://reader035.vdocuments.us/reader035/viewer/2022070408/56649e675503460f94b6263b/html5/thumbnails/10.jpg)
Mitosis
4 phases:
1st – Prophase
2nd – Metaphase
3rd – Anaphase
4th – Telophase
![Page 11: What do all cells require to survive? A complete set of genetic instructions – to produce required molecules – to direct life processes Genetic instructions](https://reader035.vdocuments.us/reader035/viewer/2022070408/56649e675503460f94b6263b/html5/thumbnails/11.jpg)
Prophase“P is for pairs”
chromosomes condensed and in pairs: 2 sister chromatids attached at the centromere
spindle fibers form
chromosomes are captured by the spindle fibers
one pair of centrioles migrates to one pole of cell, the other pair migrates to opposite pole of cell
nuclear envelope disintegrates and nucleolus disappears
![Page 12: What do all cells require to survive? A complete set of genetic instructions – to produce required molecules – to direct life processes Genetic instructions](https://reader035.vdocuments.us/reader035/viewer/2022070408/56649e675503460f94b6263b/html5/thumbnails/12.jpg)
chromatin
nucleolus
nucleus
centrioles
condensingchromosomes
![Page 13: What do all cells require to survive? A complete set of genetic instructions – to produce required molecules – to direct life processes Genetic instructions](https://reader035.vdocuments.us/reader035/viewer/2022070408/56649e675503460f94b6263b/html5/thumbnails/13.jpg)
Metaphase“M is for middle”
• chromosomes align along the equator (middle) of the cell
centrioles
spindle fibers
chromosomes
![Page 14: What do all cells require to survive? A complete set of genetic instructions – to produce required molecules – to direct life processes Genetic instructions](https://reader035.vdocuments.us/reader035/viewer/2022070408/56649e675503460f94b6263b/html5/thumbnails/14.jpg)
Anaphase“A is for apart”
• sister chromatids separate• spindle fibers attached at centromeres shorten and pull chromatids poleward
![Page 15: What do all cells require to survive? A complete set of genetic instructions – to produce required molecules – to direct life processes Genetic instructions](https://reader035.vdocuments.us/reader035/viewer/2022070408/56649e675503460f94b6263b/html5/thumbnails/15.jpg)
Telophase“T is for Two nuclei”
• spindle fibers disintegrate• nuclear envelopes form around both groups of chromosomes making TWO nuclei
• chromosomes revert to chromatin• nucleoli reappear
![Page 16: What do all cells require to survive? A complete set of genetic instructions – to produce required molecules – to direct life processes Genetic instructions](https://reader035.vdocuments.us/reader035/viewer/2022070408/56649e675503460f94b6263b/html5/thumbnails/16.jpg)
chromosomesdecondensing
nuclear envelopereforming
nucleolus reappears
pinching of cellmembrane at equator
![Page 17: What do all cells require to survive? A complete set of genetic instructions – to produce required molecules – to direct life processes Genetic instructions](https://reader035.vdocuments.us/reader035/viewer/2022070408/56649e675503460f94b6263b/html5/thumbnails/17.jpg)
cytokinesis
End of cycle – Cytokinesis – membranes finish pinching apart and cells become separate.
![Page 18: What do all cells require to survive? A complete set of genetic instructions – to produce required molecules – to direct life processes Genetic instructions](https://reader035.vdocuments.us/reader035/viewer/2022070408/56649e675503460f94b6263b/html5/thumbnails/18.jpg)
• Differences in Plant cells: – stiff cell wall makes pinching impossible – Golgi complex buds off vesicles filled with carbohydrate – vesicles line up at equator and fuse, producing a structure called the cell plate – cell plate becomes new cell wall between the two cells