Biology - Online Test
Q1. Chitin occurs in cell wall of
Answer : Option C
Explaination / Solution:
The cell wall of fungi is made of chitin,complex sugar molecules. The cell wall of plants are made up of cellulose.
Q2. In humans, height shows a lot of variation. It is an example of
Answer : Option D
Explaination / Solution:
Height of human being is not controlled by single pair of gene. A number of genes participate to form growth hormone that actually triggers the height of individual.
Q3. Read the following :
i. The instrument used for recording heart’s electrical events is named electrocardiogram.
ii. In any ECG the part of base line between any two deflections is called interval.
iii. Abnormality in the working of heart changes wave pattern of ECG.
i. The instrument used for recording heart’s electrical events is named electrocardiogram.
ii. In any ECG the part of base line between any two deflections is called interval.
iii. Abnormality in the working of heart changes wave pattern of ECG.
Answer : Option B
Explaination / Solution:
ECG is a graphical representation of the electrical activity of the heart during a cardiac cycle.
Q4. Use of biocontrol measures will greatly reduce our dependence on
Answer : Option B
Explaination / Solution:
The use of biocontrol measures will greatly reduce our dependence on toxic chemicals and pesticides. Insects and pests are not killed in this method but kept undercontrol.
Q5. In eukaryotic organisms aerobic respiration takes place in presence of
Answer : Option C
Explaination / Solution:
Aerobic means “with air”. This type of respiration needs oxygen for it to occur so it is called aerobic respiration.
The word equation for aerobic respiration is:
Glucose + Oxygen Carbon dioxide + Water + Energy
The chemical equation is:
C6H12O6 + 6O2 6CO2 + 6H2O + 2900 kJ/mol
Q6. Mass destruction of aquatic life will be caused by:
Answer : Option D
Explaination / Solution:
Mass destruction of aquatic life will be caused by broad spectrum pesticides. Broad spectrum pesticides are effective against large number of pests whether useful or harmful. These pesticides reaches to water bodies along with rain water.
Q7. Inflorescence which shows indefinite growth and bears a number of flowers due to active growing point is called
Answer : Option D
Explaination / Solution:
In recemose inflorescence indefinite growth occurs and bears a number of flowers due to active growing point.
Q8. Division of nucleus without being followed by cytokinesis results into
Answer : Option A
Explaination / Solution:
The division of nucleus or karyokinesis without being followed by cytokinesis results into increase in the content of nucleus, a condition known as multinucleate condition.
Q9. Overhangs produced by restriction enzymes are called as
Answer : Option D
Explaination / Solution:
Longer overhangs are called cohesive ends or sticky ends. They are most often created by restriction endonucleases when they cut DNA.
Q10.
Counter current mechanism :
i. It operates in all vertebrates.
ii. It produces hypertonic urine.
Answer : Option D
Explaination / Solution:
Counter current mechanism operates in mammals but not in all vertebrates. Due to counter current mechanism it produces hypertonic urine, highly concentrated.
