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ÁREA: | Natural Sciences and Environmental Education: Biology | GRADE: 8th |
TOPIC: | Cellular reproduction |
TEACHER: | Roger Figueroa Paz |
TIME: | FROM: September26th2012 | TO: October 26th2012 |
INTRODUCTION
The cells need to get nutrients (biomolecules) to warranty their proper activity. The nutrients exchange for cells and theconnections between different parts of the cell arepossible thanks to membranes that control and regulate this communication. All previous chain of events, included in nutrition andthe function of relationship, are necessary with the purpose to perform an organized and success reproduction process: cell division.

Cell division is the process that cells go through in order to be divided. Cells may be divided for several reasons, and there are twotypes of cell division depending on the purpose. The cell division associated with sexual reproduction is one type, called meiosis. The other type, the cell division associated with growth and cell replacement or repair, is called mitosis. In both types, the nucleus splits and DNA is replicated.

CELLULAR DIVISION CONCEPT MAP

GLOSSARY
In this list, you will find keywords that guide the periodtopic and you must learn and understand them.

* cell cycle: The sequence of events in the life of a cell, from one division to the next.
* cell division: The separation of one cell into two daughter cells, involving both nuclear Division (mitosis) and subsequent cytoplasmic division (cytokinesis). The process in reproduction and growth by which a cell divides to form daughter cells. Alsoknown as mitosis and meiosis.
* centrioles: Centrioles are cylindrical structures.Centrioles are found in animal cells and help to organize the assembly of microtubules during cell division. Centrioles replicate during the interphase stage of mitosis and meiosis. The position of the centriole determines the position of the nucleus and plays a crucial role in the spatial arrangement of thecell.
* chromatid: One of the two identical strands of DNA and protein that forms a replicated chromosome. The two sister chromatids are joined at the centromere
* chromatin: The complex of DNA and proteins which condenses to form a chromosome during cell division
* chromosome:An organized structure of DNA and protein found in cells
* cytokinesis: The division of the cytoplasm andorganelles into two daughter cells during cell division; normally occurs during telophase of mitosis
* diploid: A cell or an organism consisting of two sets of chromosomes: usually, one set from the mother and another set from the father. In a diploid state the haploid number is doubled, thus, this condition is also known as 2n
* duplicated chromosome: A eukaryotic chromosome following DNAreplication; consists of two sister chromatids joined at the centromeres
* gamete: a haploid sex cell formed in sexually reproducing organisms
* haploid: (1) The number of chromosomes in a gamete of an organism, symbolized by n. (2) A cell or an organism having half of the number of chromosomes in somatic cells.
* kinetochore: A protein structure that forms at the centromere regionsof chromosomes; attaches the chromosomes to the spindle.
* meiosis: In eukaryotic organisms, a type of nuclear division in which a diploid nucleus divides twice to form four haploid nuclei.
* microtubules: Are rigid hollow and dynamic structures that undergo continual assembly and disassembly within the cell. They function both to determine cell shape and in a variety of cell movements,including some forms of cell locomotion, the intracellular transport of organelles, and the separation of chromosomes during mitosis.
* mitosis: A type of nuclear division, used by eukaryotic cells, in which one copy of each chromosome (already duplicated during interphase before mitosis) moves into each of two daughter nuclei; the daughter nuclei are therefore genetically identical to each...