Latest questions in this category.
The fungal sexual cycle involves plasmogamy, the fusion of protoplasms; karyogamy, the fusion of nuclei; and meiosis in the zygote, which produces haploid spores.
Ref: NCERT Class 11 Biology Chapter 2: Biological Classification Bacteria - Structure and Economic Importance
Citrus canker is listed as a bacterial disease. Malaria is caused by Plasmodium, sleeping sickness is associated with parasitic flagellated protozoans, and wheat rust is caused by Puccinia, a fungus.
Ref: NCERT Class 11 Biology Chapter 2: Biological Classification Bacteria - Structure and Economic Importance
Cyanobacterial colonies are generally surrounded by a gelatinous sheath and often form blooms in polluted water bodies. Cyanobacteria may be unicellular, colonial or filamentous.
Ref: NCERT Class 11 Biology Chapter 2: Biological Classification Bacteria - Structure and Economic Importance
Viruses are inert outside their specific host cells. After infecting a living cell, they take over the host-cell machinery to produce new viral particles; therefore, they are obligate parasites.
Ref: NCERT Class 11 Biology Chapter 2: Biological Classification Bacteria - Structure and Economic Importance
Bacteria reproduce mainly by fission, but under unfavourable conditions some of them produce spores. These spores help them persist when environmental conditions are unsuitable.
Ref: NCERT Class 11 Biology Chapter 2: Biological Classification Bacteria - Structure and Economic Importance
Vibrio is the comma-shaped bacterial form. Coccus is spherical, Bacillus is rod-shaped and Spirillum is spiral-shaped.
Ref: NCERT Class 11 Biology Chapter 2: Biological Classification Bacteria - Structure and Economic Importance
Bacteria reproduce mainly by fission. Under unfavourable conditions, some bacteria may also produce spores, and a primitive type of DNA transfer may occur between bacterial cells.
Ref: NCERT Class 11 Biology Chapter 2: Biological Classification Bacteria - Structure and Economic Importance
Fungal cell walls are composed of chitin and polysaccharides.
Ref: NCERT Class 11 Biology Chapter 2: Biological Classification Bacteria - Structure and Economic Importance
Bacteria reproduce mainly by fission. Some produce spores under unfavourable conditions, while a primitive type of sexual reproduction may occur through the transfer of DNA from one bacterial cell to another.
Ref: NCERT Class 11 Biology Chapter 2: Biological Classification Bacteria - Structure and Economic Importance
The association is a lichen. The algal phycobiont prepares food, while the fungal mycobiont provides shelter and absorbs water and minerals. Because lichens do not grow in polluted areas, they indicate air pollution.
Ref: NCERT Class 11 Biology Chapter 2: Biological Classification Bacteria - Structure and Economic Importance
The organism is a cyanobacterium. Cyanobacterial colonies commonly possess a gelatinous sheath and may form blooms in polluted water. Some forms, such as Nostoc and Anabaena, fix atmospheric nitrogen in heterocysts.
Ref: NCERT Class 11 Biology Chapter 2: Biological Classification Bacteria - Structure and Economic Importance
The features identify cyanobacteria. Cyanobacteria are photosynthetic prokaryotes containing chlorophyll a. Forms such as Nostoc and Anabaena may fix atmospheric nitrogen in specialised cells called heterocysts.
Ref: NCERT Class 11 Biology Chapter 2: Biological Classification Bacteria - Structure and Economic Importance
