CBSE 11TH BIOLOGY - Online Test
Q1. Which phase of M-stage is called as invisible phase?
Answer : Option D
Explaination / Solution:
S-phase of M-stage is called as invisible phase of cell cycle because during this phase synthesis of DNA takes place which is not visible to the naked eye. There is only imbalance of Nucleoplasmic ratio.
Q2. The epithelial cells of Bowman’s capsule are called:
Answer : Option A
Explaination / Solution:
Podocytes are cells in the Bowman's capsule in the kidneys that wrap around capillaries of the glomerulus. The Bowman's capsule filters the blood, retaining large molecules such as proteins while smaller molecules such as water, salts, and sugars are filtered as the first step in the formation of urine.
Q3. Which epidermis of leaf contains more stomata?
Answer : Option A
Explaination / Solution:
Stomata is present more on the lower surface of leaf. The lower surface of leaf is called abaxial part of leaf that is away from direct sunlight to prevent excess of water loss.
Q4. In dicotyledonous plants, girth of stem and root increase due to
Answer : Option C
Explaination / Solution:
Secondary growth is the result of the activity of the two lateral meristems, the cork cambium and vascular cambium. Arising from lateral meristems, secondary growth increases the girth of the plant root or stem, rather than its length.
Q5. The Darwin of 20th century is
Answer : Option B
Explaination / Solution:
Born on 5 July 1904, in Kempten, Germany, ERNST MAYR, the Harvard University evolutionary biologist who has been called ‘The Darwin of the 20th century’, was one of the 100 greatest scientists of all time.
Q6. The vertebral formula of human is :
Answer : Option A
Explaination / Solution:
The vertebral column is differentiated into cervical (7), thoracic (12), lumbar (5), sacral (5-fused) and coccygeal (4-fused) regions starting from the skull.
Q7. Passive water absorption by root system is due to
Answer : Option C
Explaination / Solution:
Absorption of water by root system is passive due to tension in sap created by transpiration. No energy molecule is required in this process, so it is passive in nature.
Q8. Epithelium covering in tongue is
Answer : Option C
Explaination / Solution:
Tongue is covered by non-keratinized squamous epithelial tissues having taste buds of different kinds in different regions of tongue.
Q9. Which bacteria help in oxidising inorganic substances?
Answer : Option C
Explaination / Solution:
Chemosynthetic autotrophic bacteria oxidise various inorganic substances such as nitrates, nitrites and ammonia and use the released energy for their ATP production. They play a great role in recycling nutrients like nitrogen, phosphorous, iron and sulphur.
Q10. Most active nitrogen fixer in Rice field is
Answer : Option C
Explaination / Solution:
Rice field contains large number of nitrogen fixing algae and bacteria. In which Aulosira fertilissima is most active nitrogen fixer in the rice field.
