Biology - Online Test
Q1.
Look at the following ECGs:
Answer : Option B
Explaination / Solution:
Both electro cardiogram (ECG) represents myocardial infarction in which heart do not receive the sufficient oxygen due to blockage of coronary artery.
Q2. The common nitrogen-fixer in paddy fields is
Answer : Option A
Explaination / Solution:
Nitrogen is obtained by plants either in nitrate or nitrite forms. Some microbes convert atmospheric nitrogen into nitrate and nitrite. The common nitrogen-fixing microbe in paddy field is Azospirillum.
Q3. Arrange the following in descending order based upon number of carbon atoms in Kreb cycle a) α-ketoglutaric acid b) citric acid c) Acetyl coA d) Succinic acid
Answer : Option C
Explaination / Solution:
In kerb cycle citric acid consists of 6C atoms ,α-ketoglutaric acid consist of 5C atoms, succinic acid consists of 4 C atoms and Acetyl co A consists of 2C atoms,
Q4. Soil pollution :
i. can be of two types- positive and negative
ii. soil erosion is an example of positive soil pollution
i. can be of two types- positive and negative
ii. soil erosion is an example of positive soil pollution
Answer : Option D
Explaination / Solution:
Addition of harmful substances in soil is called soil pollution. Soil pollution is of two types positive and negative. Addition of organic wastes increase the productivity so positive. Soil erosion is the removal of top fertile layer of soil that reduce its fertility so it is a negative soil pollution.
Q5. The form of thalamus in which ovary is at tops and stamens, petals and sepals are born below is called
Answer : Option D
Explaination / Solution:
In hypogamous flowers the ovary is at tops and stamens, petals and sepals are borne below on the thalamus. The ovary is called superior.
Q6. In the metaphase stage, the chromosomes are made up of
Answer : Option A
Explaination / Solution:
At metaphase stage, the chromosome is made up of two sister chromatids formed due to longitudinal splitting of the chromatids, which are held together by the centromere.
Q7. Primers are
Answer : Option A
Explaination / Solution:
Primers are chemically synthesized oligonucleotides that are complementary to the regions of DNA and the enzyme DNA polymerase.
Q8. If in glomerular capillaries, pressure of blood is 75 mm Hg, osmotic pressure of plasma proteins is 30 mm Hg, and hydrostatic pressure of fluid in renal tubule is 25 mm Hg then net force or the filtration pressure will be calculated as :
Answer : Option D
Explaination / Solution:
Net force of filtration pressure is equal to the blood pressure of glomerular capillaries minus sum of the osmotic pressure of plasma and hydrostatic pressure of fluid in renal tubule. So, filtration pressure = 75 – [ 30 + 20 ] mm Hg.
Q9. Lamarck theory of organic evolution is usually known as
Answer : Option B
Explaination / Solution:
Lamarck theory of organic evolution is also known as inheritance of acquired traits. He believed that the character an individual gain in his life time is also passed to next generation.
Q10. The casparian thickening occurs in the cells of
Answer : Option C
Explaination / Solution:
The tangential as well as radial walls of the endodermal cells have a deposition of water-impermeable, waxy material-suberin-in the form of casparian strips.
