Biological Classification Important Questions Botany Notes Chapter 2, for Class 12-CBSE

EXERCISE

1. Archaebacteria do not show
   1. Peptidoglycan and D- amino acids in cell wall
   2. Introns in DNA
   3. Branched chain lipids in cell membrane
   4. Ribosomal proteins with highly acidic nature
2. Methanogens are nutritionally
   1. Photolithotrophs
   2. Chemolithotrophs
   3. Photoheterotrophs
   4. Chemoheterotrophs
3. Thermoacidophiles are capable of withstanding extremely low pH and temperature due to the
   1. Presence of branched chain of lipid in cell membrane
   2. Presence of resistant enzyme which can operate in basic conditions
   3. Presence of higher concentration of KCI in their cells.
   4. More than one option is correct
4. Smallest wall – less monerans
   1. Develop fried egg appearance in culture
   2. Are motile
   3. Have definite shape
   4. Are mostly saprophytic
5. Which one the following organism reproduces by means of elementary bodies formation ?
   1. Frankia
   2. coli
   3. PPLO
   4. BGA
6. Which group of monerans played significant role in the evolution of aerobic forms of life?
   1. Mycoplasma
   2. Cyanobacteria
   3. Archaebacteria
   4. Actinomycetes
7. The characteristic photosynthetic pigments in cyanobacteria are
   1. Chlorophyll a and c
   2. Chlorophyll a and carotenes
   3. Chlorophyll a and phycobilins
   4. Chlorophyll a, carotenoids and phycobilins
8. Heterocystous blue- green algae are
   1. Anabaena and Lyngbya
   2. Nostoc and Aulosira
   3. Phormidium and Oscillatoria
   4. Spirulina and oscillatoria
9. Gram positive filamentous bacteria with mycolic acid in their cell wall are known as
   1. Archaebacteria
   2. Ray fungi
   3. Club fungi
   4. Blue green algae
10. Witches broom disease in plants is caused by
    1. Rhizobium
    2. Mycoplasma
    3. Actinomycetes
    4. Cyanobacteria

Did You Know?

1. In 1798 , Edward Jenner used cowpox virus for immunizing people against small pox.
2. Pasteurization simply kills bacteria but does not sterilize milk. It frees the latter of all vegetative cells of pathogens, but not endospores.
3. Mycobacterium and Xanthomonas form nodules in leaves of Ardisia, Pavetta.
4. Bacterial cell membrane contains pentacyclic sterol like molecule termed as hopanoids as membrane stabilizer.

5.Kleinberger discovered tuberculosis and anthrax bacteria & developed “L-form” bacteria.

6. H.T. Ricketts described some new types of organisms (now considered a type of bacteria ) in the blood of victims of Rocky Mountain spotted fever and similar organisms were called Rickettsiae, in honour of Ricketts. They occur as obligate intracellular parasites. The Q fever is caused by Coxiella burnetti. Mountain fever is caused by Rickettsia rickettsii.
7. Chlamydiae : They are obligate intracellular parasite of vertebrates. They reproduce by elementary bodies. They do not have their own ATP generating system and obtain this energy from host. So that they are called energy parasite.

Diseases

Trachoma (eye disease)  –        C. trachomatis

Conjuctivitis                  –        C. trachomatis

Psittacosis (influenza like )      –        C. psittaci

8) Bergey gave classification of bacteria in the “Manual of Determinative Bacteriology”

9) Joseph Lister developed the technique of aseptic cultures.

10) Nostoc develops symbiotic associations with Gunnera stem and Trifolium roots.