EXCRETION
Waste product are diffused through general body surface, egested through cytopyge and by contractile vacuoles.
Respiration. It take place through general body surface. Gaseous exchange takes place by diffusion; oxygen is taken in form the surrounding water and carbon dioxide is diffused in water.
Osmoregulation. Water control (osmoregulation) is regulated by two contractile vacuoles. Each contractile vacuole is provided with 6-11 radiating canals which go deep into the endoplasm and collect excess of water. The water from the canal is stored in the contractile vacuoles from where it is discharged to the out side through temporary structure.
REPRODUCTION IN PARAMECIUM
Paramecium reproduces both by asexual and sexual means.
A. Asexual reproduction. It takes place generally by binary fission. In some species like P. aurelia endomixis and hemixis also take place.
B. Sexual reproduction. During favourable condition, it take place by conjugation. In some species autotomy, cytogamy or encystment also occur.
BINARY FISSION IN PARAMECIUM
Under favourable survival conditions, it reproduces by binary fission . During this process, the animal body becomes flat and spindle shaped. The activities like locomotion, nutrition, etc. cease and animal settles down at the bottom of water. During this type of reproduction the animal divides transversely into two unequal halves. The micronucleus elongated and undergoes a sort of mitosis while the macronucleus elongated and divides transversely into two parts automatically. The cleavage starts near the middle of the body. This deepens and finally the two individuals are separated. The buccal groove goes to one half while the other develops its own. New contractile vacuoles are formed in each daughter colony. Paramecium, stages in binary fission.
Waste product are diffused through general body surface, egested through cytopyge and by contractile vacuoles.
Respiration. It take place through general body surface. Gaseous exchange takes place by diffusion; oxygen is taken in form the surrounding water and carbon dioxide is diffused in water.
Osmoregulation. Water control (osmoregulation) is regulated by two contractile vacuoles. Each contractile vacuole is provided with 6-11 radiating canals which go deep into the endoplasm and collect excess of water. The water from the canal is stored in the contractile vacuoles from where it is discharged to the out side through temporary structure.
REPRODUCTION IN PARAMECIUM
Paramecium reproduces both by asexual and sexual means.
A. Asexual reproduction. It takes place generally by binary fission. In some species like P. aurelia endomixis and hemixis also take place.
B. Sexual reproduction. During favourable condition, it take place by conjugation. In some species autotomy, cytogamy or encystment also occur.
BINARY FISSION IN PARAMECIUM
Under favourable survival conditions, it reproduces by binary fission . During this process, the animal body becomes flat and spindle shaped. The activities like locomotion, nutrition, etc. cease and animal settles down at the bottom of water. During this type of reproduction the animal divides transversely into two unequal halves. The micronucleus elongated and undergoes a sort of mitosis while the macronucleus elongated and divides transversely into two parts automatically. The cleavage starts near the middle of the body. This deepens and finally the two individuals are separated. The buccal groove goes to one half while the other develops its own. New contractile vacuoles are formed in each daughter colony. Paramecium, stages in binary fission.
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