CBSE 11TH BIOLOGY - Online Test
Q1. Length of DNA with 23 base pairs is
Answer : Option C
Explaination / Solution:
The distance between two base pairs in DNA is 3.4 . The length of DNA with 23 base pairs is 23x 3.4 = 78.2 .
Q2. Dough kept overnight in warm place becomes soft and spongy due to
Answer : Option C
Explaination / Solution:
Fermentation is a kind of anaerobic respiration in absence of oxygen to produce ethanol and carbon dioxide gas. Dough kept overnight in warm place becomes soft and spongy due to carbon dioxide gas released during fermentation.
Q3. Cell growth results in disturbing the ratio between
Answer : Option B
Explaination / Solution:
Cell growth results in disturbing the ratio between the nucleus and the cytoplasm. It therefore becomes essential for the cell to divide to restore the nucleo-cytoplasmic ratio. Cell becomes stable when N/C ratio is 1.
Q4. Which one is less general in characteristic as compared to genus
Answer : Option A
Explaination / Solution:
Division is the highest category of hierarchy which contain organisms having only a few common characters. On the other hand, species belongs to lowest level so, the organisms have more common characters.
Q5. In angiosperms, main water and mineral transporting elements is
Answer : Option C
Explaination / Solution:
In angiosperms, the main water and mineral transporting element is tracheids. Vessels also transport water and mineral in angiosperms.
Q6. Antiauxin used in picking cotton bolls is
Answer : Option C
Explaination / Solution:
TIBA (2,3,5 Triidobenzoic acid) acts as antiauxin that inhibit root and shoot formation. TIBA is used as antiauxin in picking cotton bolls.
Q7. The form of thalamus in which ovary is at top and stamens, petals and sepals are borne below is called
Answer : Option A
Explaination / Solution:
In the hypogynousflower, thegynoecium occupies the highest position while the other parts are situatedbelow it. The ovary in such flowers is said to be superior.
Q8. How many times do nymphs moult to reach the adult form of cockroach?
Answer : Option D
Explaination / Solution:
When the ootheca hatches, tiny nymph come out. It grows by undergoing moulting about 13 times to reach the adult form.
Q9. Which possess acellular structure?
Answer : Option A
Explaination / Solution:
A bacteriophage is a virus that infects and replicates within a bacterium.
Except bacteriophage, all possess cellular structure.
Q10. Main function of lenticel is
Answer : Option C
Explaination / Solution:
Lenticels are minute pore in stems through which exchange of gases takes place between plant and atmosphere.
