Complete O/L notes biology Spirogyra
Scientific name: spirogyra
Common name: spirogyra
Spirogyra is an alga. It is green in color and the cell has a cellulose cell wall and a definite nucleus. They have chloroplast which is spiral with pyrene on it.
Spirogyra are filamentous green alga which are found in fresh water. It also has a cytoplasmic stand and large vacuole spirogyra carried out asexual production by fragmentation and sexual reproduction by conjugation.
Spirogyra can be found in fresh water such as river ponds, ditches and slow running streams. Some may be found on moist branches or wet branches.
Spirogyra is a green filamentations alga which is slimy to the touches.
Spirogyra is the green filamentous alga which is slimy because it is covered by a gelatinous outer layer
Each cell is also covered by a cell wall of cellulose the nucleus is suspended in the middle by a cytoplasm stand. The cell has a large vacuole containing cell sap. The chloroplast is spiral and it contains paranoids.
///////////////////////////////////////diagram of spirogyra////////////////////////
The spirogyra grows by increase in length but when a filament is cut into pieces, each grows into a new spirogyra filament.
Considering the fat that spirogyra has single cells in the rows, oxygen diffuses into the organism and carbon dioxide diffuses out.
Spirogyra is green because it contains chlorophyll in the presence of carbon dioxide, mineral salt and water with energy coming from sunlight spirogyra can manufacture its own food through the presence of photosynthesis.
Spirogyra reproduces asexually as well as sexually
7.7.1 Asexual reproduction in spirogyra
Asexual reproduction can go on by fragmentation that is breaking up of filament and after this, binary fission can go on to reproduce a new filament.
7.7.2. sexual reproduction in spirogyra
- Sexual reproduction is by conjugation which takes place in the following order two filaments come and lie side by side.
- The filaments develop production protuberances
- The protuberances meet and the wall between them breaks down to form a conjugation tube. The content shrinks and become round and one content flow into the other.
- The cell content fuse together and a zygote is formed
- The zygote develops a thick dark wall around the cell to form a zygote spore
- The zygote spore geminates become a new filament
- It helps in the fixation of Caro dioxide during photosynthesis
- It releases oxygen into the atmosphere which can be used by other organism for respiration
- Some algae used as food
- Some algae are used as fertilization
- They are used as a source of protein for animals and human organisms of feeding
- Alginic acid which is extracted from algae is used as a thicker
- When algae overcrowd the bodies as water, they contaminate the water and cause pollution
- Algae are the bases of food chain
- Algae may grow on water on block the water for navigation.
|It has rigid cell||It has flexible cell surface membrane|
|The cytoplasm at the corner||The cytoplasm is spread all over the cell|
|The vacuoles the corner||The vacuoles are small and distributed|
|The vacuole is suspended by a cytoplasmic stand||The cytoplasmic stand is absent|
|It is green in color showing that it contains chloroplast with chlorophyll||It is colored and has no chloroplast|
|The cells form chains||The cell is single|
|Since they contain chlorophyll it can manufacture their own food through photosynthesis||They cannot manufacture their own food|
|Lacks pseudopodia for movement so it is sessile||They contain pseudopodia for movement so they are motile|
|It has a definite shape||Has an irregular shape|
|Have permanent organelles (cell part)||Has sudo-organels. Which are formed when needed|
|Has one type of vacuole||Have two types of vacuoles (food and contractile vacuole)|
|Is relatively smaller than amoeba||Is relatively longer than spirogyra|