The endothecium lies internal to the epidermis.It is made up of flattened cells which are protective in function. The epidermis is the outermost layer of the anther wall.viz., epidermis, endothecium, middle layers and tapetum. The wall of the anther can be differentiated into four layers. The anther consists of two main parts, viz., anther wall and microsporangium or pollen sac. Internally it shows four chambers called microsporangia or pollen sacs. of anther ( Transverse section of anther) : Biflagellate zoospores are formed in algae Chlamydomonas.Flagellated zoospores when liberated can grow independently into new individuals.It occurs by production of motile zoospores that are formed in sporangia.Buds may be one or more and on separation they grow as new individual.ģ-Spore formation : It is of very common occurrence in lower plants.Mother cell produces small outgrowth which is known as bud.It is observed in favourable condition.It is of very common occurrence in unicellular organism yeast.These fragments are formed due to different reasons like accidental breakdown, death and decay of cells, etc.Ģ-Budding : Budding in plants is an artificial method of propagation in which a single bud is joined or grafted on the stock plant. Multicellular organisms break into small pieces called fragments which develop into new plant. However, when exposed to harsh conditions like drought, it can slow down its growth rate until more favorable conditions arise.1-Fragmentation : Fragmentation: It is a type of asexual reproduction observed in lower plants, e.g. Under normal circumstances, it can divide every 48 hours. For instance, the Deinococcus radiodurans is an extremophilic bacteria that can survive a thousand times more radiation than a person can. These bacteria can survive extremely harsh conditions such as high temperatures, high salinity, highly acidic environments, and more. On the other end of the spectrum are the extremophiles. It divides every 15 to 20 hours, which is very slow when compared to other pathogenic bacteria such as Escherichia coli, which can divide every 20 minutes. Mycobacterium tuberculosis is the bacterium that causes tuberculosis in humans. The ambient temperature of the human body is 37 ☌, which means many of the disease-causing bacteria are mesophiles. For instance, mesophiles thrive at moderate temperatures ranging from 20 ☌ to 45 ☌. These conditions include pH levels, temperature, oxygen, light, moisture, osmotic pressure. Each species requires specific conditions for its growth.The time required by organisms to double their number of cells is called doubling time. The process of binary fission is usually rapid, and its speed varies among species.
When the cell starts to get drawn apart, the original (actual) and replicated chromosomes get apart. In this process, the single DNA molecule begins replication and then attaches each copy to various parts of the cell membrane.
It is a primary method of reproduction in prokaryotic organisms. In this process, each daughter cell receives one copy of its parent DNA.pumilus, Escherichia coli, Clostridium perfringens, Corynebacterium diphtheriae, Amoeba, Paramecium, Euglena, Ceratium, etc. Organisms that reproduce by binary fission include Bacillus subtilis, B.In protozoans like amoeba, Paramecium, Euglena, however, the process might differ in cell splitting and in how the cytoplasm divides.The process involves the division by utilizing the FtsZ protein, including chromosomal replication, chromosomal segregation, and cell splitting. Most of the bacteria reproduce by this process.
Both prokaryotes and eukaryotes are divided by binary fission.
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