Cell Reproduction
- Created by: Eleanor Izzard
- Created on: 04-01-13 10:55
View mindmap
- Cell Reproduction
- Clones
- Natural
- asexual reproduction produces genetically identical cells
- plants have specialised parts that are derived from the adult plant cells, they can produce many new organisms that are genetically identical
- known as Vegetative Propagation
- plants have specialised parts that are derived from the adult plant cells, they can produce many new organisms that are genetically identical
- Bacteria are prokaryotes, they have single, naked strands of DNA that is in their cytoplasm
- they may also have plasmids of DNA that can contain genes for antibiotic resistance
- because bacteria can swap plasmids, they are used in genetic engineering
- Bacteria divide by binary fisson (mitosis can only apply when chromo-somes are used)
- they may also have plasmids of DNA that can contain genes for antibiotic resistance
- asexual reproduction produces genetically identical cells
- Artificial
- cuttings taken from plants can be made to grow into genetically identical adult plants
- In Animals : tissue biopsy is taken from donor animal
- donor cells are grown in tissue culture
- donor cell nucleus is transferred to recipient egg
- cloned embryo is transferred to surrogate mother
- pregnancy is monitored by ultrasound
- cloned embryo is transferred to surrogate mother
- donor cell nucleus is transferred to recipient egg
- donor cells are grown in tissue culture
- genetically identical cells or organsisms derived from one parent
- Natural
- Stem Cells
- cells that have the capability to divide and to develop into any of several different cell types
- in young embryos stem cells can develop into any of the cell types found in the adult - they are TOTIPOTENT
- In a small number of adult cells stem cells can be found - they are PLURI-POTENT - able to develop into several cell types
- in bone marrow, stem cells can produce all types of blood and bone cell
- stem cells have the capability to be widely used in medical treatments - using an individuals own cells to replace damaged/ diseased cells
- cells that have the capability to divide and to develop into any of several different cell types
- Sexual Reproduction
- fusing of two nuclei, usually from 2 different individuals, in order to produce off spring
- each cell contributes half of the total genetic information (genome)
- special cells containing half the number of chromo-somes must be produced - GAMETES
- fusion of 2 gametes produces a Zygote, which can than divide by mitosis to grow into a new individual organism
- special cells containing half the number of chromo-somes must be produced - GAMETES
- Meiosis
- takes place in specific regions of the adult organism - gonads
- normal adult cells of most eukaryotes contain 2 sets of chromo-somes - DIPLOID
- their genome consists of a pair of homologous chromo-somes, each containing the same genes, but not necessarily the same alleles of each gene
- during meiosis, one member of each homologous pair goes into each daughter cell
- the daughter cells are HAPLIOD and are not genetically identical
- the haploid daughter cells differ because each pair of homologous chromo-somes separates independently of each other. Each contains specific alleles of each gene on the members of the homologous chromo-somes they recieve
- the daughter cells are HAPLIOD and are not genetically identical
- during meiosis, one member of each homologous pair goes into each daughter cell
- their genome consists of a pair of homologous chromo-somes, each containing the same genes, but not necessarily the same alleles of each gene
- normal adult cells of most eukaryotes contain 2 sets of chromo-somes - DIPLOID
- takes place in specific regions of the adult organism - gonads
- Division
- in animals, many cells are capable of cytokinesis and mitosis - so organisms can replace cells by producing new ones
- in plants only the cells in special growing regions (meristems) known as meristem cells can divide that way
- meristems are located at the root and shoot tips and in a ring of tissues in the stem or trunk. These small parts of the plant are responsible for the growth of the whole organism
- Cytokinesis
- in animal cells, starts from the outside, nipping in the cell membrane and cytoplasm along what is a 'cleavage furrow'
- in plant cells, it starts with the formation of the cell plate where the spindle equator was. The cell lays down new membrane and cell wall material along the plate - CELL PLATE - not solid, but a single plane which the new cell wall forms
- Yeast cells under cytokinesis by producing a small bud that nips of the cell - BUDDING
- Clones
Comments
No comments have yet been made