2.6.4 The Significance Of Mitosis

Question 1

Significance of Mitosis

Answer 1

Mitosis is the process of nuclear devision by which two genetically identical daughter nuclei are produced that are also genetically identical to the parent nucleus
The process of mitosis is of great biological significance and is fundamental to many biological processes

Question 2

Growth of Multicellular Organisms

Answer 2

The two daughter cells produced are genetically identical to one another (cells) and have the same number of chromosomes as the parents cell
This enables unicellular zygotes (as the zygote divides by mitosis) to grow into multicellular organisms
Growth may occur accords the whole body of the organism to be confined to certain regions, such as in the meristems (growing plants) in cells

Question 3

Replacement of Cells & Repair of Tissue

Answer 3

Damaged tissues can be repaired by mitosis followed by cell division
As cells are constantly dying, they need to be continuously replaced by genetically cells
In humans, for example, cell replacement occurs particularly rapidly in the skin and the lining of the gut
Some animals can regenerate body parts
- for example, zebrafish can regenerate fins and axolotls regenerate legs and their tail amongst other parts

Question 4

Asexual Reproduction

Answer 4

Asexual reproduction is the production of new individuals of a species by a single parent organism
- the offspring are genetically identical to the parent
For unicellular organisms, such as Amoeba, cell division results in the reproduction of genetically identical offspring
For multicellular organisms, new individuals grow from the parent organisms (by cell division) and detach (‘bud off’) from the parent in different ways
This type of reproduction can be observed in different plant, fungi and animal species
Some examples of these are budding Hydra and yeast and runners from strawberries