the cell cycle
DESCRIPTION
This presentation was done by me in 2010. The source of the images is written in the second slideTRANSCRIPT
![Page 1: The Cell Cycle](https://reader035.vdocuments.us/reader035/viewer/2022081518/549f7912ac79593d768b4a13/html5/thumbnails/1.jpg)
CHAPTER 11: ILUSTRATED.
Felipe Rodríguez
![Page 2: The Cell Cycle](https://reader035.vdocuments.us/reader035/viewer/2022081518/549f7912ac79593d768b4a13/html5/thumbnails/2.jpg)
All Images taken form:Audeirk, D. Audesirk, J & Byers, B. (2008) Biology with Physiology: Life on Earth. New Jersey. : Pearson.
![Page 3: The Cell Cycle](https://reader035.vdocuments.us/reader035/viewer/2022081518/549f7912ac79593d768b4a13/html5/thumbnails/3.jpg)
ASEXUAL REPRODUCTION.
(a) Paramecium sp. Is a protists, a microorganism.
(b) Yeast, a unicellular fungus reproduces asexually.
(c) Hydra a sea animal, reproduces a sexually. It starts growing a bud until it grows big enough to be an independent organism.
![Page 4: The Cell Cycle](https://reader035.vdocuments.us/reader035/viewer/2022081518/549f7912ac79593d768b4a13/html5/thumbnails/4.jpg)
PROKARYOTIC CELL CYCLE.
Prokaryotic Cell Cycle consist of DNA growth and former cell division.Cell Division in Prokaryotic cells is called BINARY FISSION.
![Page 5: The Cell Cycle](https://reader035.vdocuments.us/reader035/viewer/2022081518/549f7912ac79593d768b4a13/html5/thumbnails/5.jpg)
EUCARYOTIC CELL CYCLE.
This cycle consist of the following main phases:1. Interphase(Yello
w).2. Cell Division
(Light Blue).Interphase has 4
phases: G1,G0, S and G2.
Cell Division could be either:
Mitosis or Meiosis
![Page 6: The Cell Cycle](https://reader035.vdocuments.us/reader035/viewer/2022081518/549f7912ac79593d768b4a13/html5/thumbnails/6.jpg)
CHROMOSOME.
A human chromosome consist of a single DNA double helix and some proteins called Histones and scaffolds.Chromosomes are a compact DNA container.
![Page 7: The Cell Cycle](https://reader035.vdocuments.us/reader035/viewer/2022081518/549f7912ac79593d768b4a13/html5/thumbnails/7.jpg)
CHROMOSOME.
These are the main features of chromosomes:1. Genes:
sequences of DNA that have an specific function.
2. Centromere: it joins two parts of the chromosome, it does NOT have to be at the center.
3. Telomeres: the “end” of the chromosome, they maintain the equilibrium and seal the chromosome’s material.
![Page 8: The Cell Cycle](https://reader035.vdocuments.us/reader035/viewer/2022081518/549f7912ac79593d768b4a13/html5/thumbnails/8.jpg)
DUPLICATED CHROMOSOME.
A duplicated chromosome consist of two identical chromosomes.
![Page 9: The Cell Cycle](https://reader035.vdocuments.us/reader035/viewer/2022081518/549f7912ac79593d768b4a13/html5/thumbnails/9.jpg)
KARYOTYPE.
A karyotype is the full set of chromosomes located at each cell of an organisms. All this chromosomes are located at the nucleus.They consist of homologues pairs. For example, chromosome 1 consists of two identical chromosomes. They share the same genes at the same order and the same length. Exception: sexual chromosomes.This photo is from a male, since it has XY, if it were from a women’s it would be XX.
![Page 10: The Cell Cycle](https://reader035.vdocuments.us/reader035/viewer/2022081518/549f7912ac79593d768b4a13/html5/thumbnails/10.jpg)
MITOTIC CELL DIVISION.
Prophase:•Chromosomes condense.•Microtubules form.•Nuclear Envelop disintegrates.•Spindle Microtubules grab the chromosomes.Metaphase:•Spindle Microtubules align the chromosomes along the cells’ “Equator”.
![Page 11: The Cell Cycle](https://reader035.vdocuments.us/reader035/viewer/2022081518/549f7912ac79593d768b4a13/html5/thumbnails/11.jpg)
MITOTIC CELL DIVISION.
Anaphase:•Sister chromatids are separated and moved to opposite sides of the cell. Microtubules push each pole apart.Telophase:•Microtubules start extending, nuclear envelop reforms and spindle microtubules disappear.
![Page 12: The Cell Cycle](https://reader035.vdocuments.us/reader035/viewer/2022081518/549f7912ac79593d768b4a13/html5/thumbnails/12.jpg)
CYTOKINESIS: ANIMAL CELLS.
Microfilaments attached to the plasmas membrane start contracting the cell’s Equator, until it divides in two.
![Page 13: The Cell Cycle](https://reader035.vdocuments.us/reader035/viewer/2022081518/549f7912ac79593d768b4a13/html5/thumbnails/13.jpg)
CYTOKINESIS: PLANT CELL.
During Cytokinesis in plan cells, once the cell is divided , the Golgi Apparatus starts sending vesicles with carbohydrates (cellulose) to start creating a cell wall in-between both daughter nuclei.
![Page 14: The Cell Cycle](https://reader035.vdocuments.us/reader035/viewer/2022081518/549f7912ac79593d768b4a13/html5/thumbnails/14.jpg)
CELL CYCLE CHECKPOINTS.
Checkpoints throughout the cell cycle:•After G1 : Is your DNA suitable and intact for it to synthesize?•After G2: Has DNA replication successfully occurred?•After Metaphase: Are all the chromosomes aligned at the Equator?
![Page 15: The Cell Cycle](https://reader035.vdocuments.us/reader035/viewer/2022081518/549f7912ac79593d768b4a13/html5/thumbnails/15.jpg)
FIRST CHECKPOINT.
Cycling-dependent kinases are proteins that are assigned to control the progress of the cell cycle.
![Page 16: The Cell Cycle](https://reader035.vdocuments.us/reader035/viewer/2022081518/549f7912ac79593d768b4a13/html5/thumbnails/16.jpg)
ALLELES.
Homologues have same of different Alleles. Alleles are variations of the same gene, that determine different characteristics.
![Page 17: The Cell Cycle](https://reader035.vdocuments.us/reader035/viewer/2022081518/549f7912ac79593d768b4a13/html5/thumbnails/17.jpg)
MEIOTIC CELL DIVISION.
Both members of a pair of homologues chromosomes are replicated before Meiosis. One chromosome is parental and the other is maternal.
![Page 18: The Cell Cycle](https://reader035.vdocuments.us/reader035/viewer/2022081518/549f7912ac79593d768b4a13/html5/thumbnails/18.jpg)
MEIOSIS I.
After MEIOSIS I, each daughter cell receives one of each pair of homologues chromosomes.
![Page 19: The Cell Cycle](https://reader035.vdocuments.us/reader035/viewer/2022081518/549f7912ac79593d768b4a13/html5/thumbnails/19.jpg)
MEIOSIS II.
After MEIOSIS II, sister chromatids separate into independent chromosomes and each daughter cell receives one of these chromosomes.
![Page 20: The Cell Cycle](https://reader035.vdocuments.us/reader035/viewer/2022081518/549f7912ac79593d768b4a13/html5/thumbnails/20.jpg)
MEIOSIS I.
![Page 21: The Cell Cycle](https://reader035.vdocuments.us/reader035/viewer/2022081518/549f7912ac79593d768b4a13/html5/thumbnails/21.jpg)
CROSSING OVER.
Crossing Over occurs at Prophase I and it adds genetic diversity to the chromosomes.
![Page 22: The Cell Cycle](https://reader035.vdocuments.us/reader035/viewer/2022081518/549f7912ac79593d768b4a13/html5/thumbnails/22.jpg)
METAPHASE I.
Homologues chromosomes are paired up taking as a reference the Equator. Each PAIR of chromatids gas a single functional kenitochore.In MITOSIS, each sister chromatids have one kenitochore.
![Page 23: The Cell Cycle](https://reader035.vdocuments.us/reader035/viewer/2022081518/549f7912ac79593d768b4a13/html5/thumbnails/23.jpg)