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Why spore formation in bacteria not considered a form of reproduction?
Reproduction means increase in number of organism by dividing the cell or by mating but in spore formation the bacteria cell undergoes some modification which helps it to pass unfavorable conditions and when conditions again become favorable then it regains its original structures so it is not reproduction but just modifications
Spore formation in bacteria is not considered a form of reproduction because the ‘mother’ dies immediately leaving her ‘daughter’ still alive. It is an immediate one-for-one substitution.
Endospore formation in bacteria is homologous to mitosis. I would even say that it is a form of asymmetric mitosis analogous to budding in yeast. One bacterial cell splits into two bacterial cells. However, one of the bacterial cells dies immediately.
The chromosome in the bacterial cell doubles and splits in endospore formation just as it does in mitosis. Biologists who study endospore formation are quite aware of the similarity between sporulation and budding.
One of the bacterial cells, referred to as the ‘mother’, squeezes all the liquid water out of the other cell, referred to as the daughter, immediately after mitosis. The ‘daughter’ becomes like a hard crystal with all the organelles arranged in a certain order.
The mother also coats the daughter in a spore case made of calcium dipicolinate and protein. The calcium dipicolinate protects the inside of the daughter from heat and chemical attack. Then the ‘mother’ cell dies.
The process of forming a bacterial endospore is referred to as sporulation. There is one active cell (the vegetative cell) before the process begins and one dormant cell (the endospore) after the process ends. Sporulation is one on one substitution.
The ‘daughter’ encased in her spore case is referred to as a bacterial endospore. The daughter remains dormant until conditions are suitable. There has to be water and other things neccessary for an active (vegetative) cell to survive. Then the calcium dipicolinate dissolves, the organelles soak up water, and the vegetative cell is free to do whatever bacteria like to do.
The process of a bacterial endospore becoming a endospore cell is called germination. The process of a vegetative bacteria becoming an endospore cell is called sporulation
Only a few species of gram-positive bacteria can form endospores. Not all gram-positive bacteria can form endospores.
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When a moist slice of bread was kept aside for a few days then some organism grew on it to form a white cottony mass which later turned black. When this slice of bread was observed through a magnifying glass, then fine thread-like projections and thin stems having bulb-like structures at the top were seen.
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