Biology - Online Test
Q1. The puffed-up appearance of dough is due to production of
Answer : Option B
Explaination / Solution:
The puffed-up appearance of dough is due to production of gas. Baking soda (sodium hydrogen carbonate) on heating release carbon dioxide gas along with sodium carbonate.
Q2. Term acid rain was coined for the first time by
Answer : Option A
Explaination / Solution:
Robert August Smith was a Scottish chemist, who investigated numerous environmental issues. He is known for his research on air pollution in 1852, in the course of which he discovered what came to be known as acid rain. He is sometimes referred to as the 'Father of Acid Rain'.
Acid rain occurs due to presence of Sulphur dioxide and nitrogen oxide in atmosphere.
Q3. Some scientist consider virus as living entities because they can
Answer : Option D
Explaination / Solution:
Virus is called as borderline of living and non-living. Viruses act as living one when inside the other living organism and reproduce very fast. When outside the living body, virus behaves as molecules without any sign of living.
Q4. The part that develops from the plumule of the embryo of a germinating seed is
Answer : Option B
Explaination / Solution:
The stem develops from the plumule of the embryo of a germinating seed.
Q5. The number of chromosome and the amount of DNA are changed in
Answer : Option A
Explaination / Solution:
S phase marks the period during which DNA synthesis or replication takes place. During this time the amount of DNA per cell doubles. If the initial amount of DNA is denoted as 2C then it increases to 4C.and even in anaphase the chromosome numbers are changed.1
Q6. Host cell membrane can be made permeable by
Answer : Option B
Explaination / Solution:
CaCl2 can be used to make the bacterial cell a permeable cell, and by introducing these cells (after CaCl2 being placed into the mixture of bacterial cells), a plasmid for ampicillin resistance can be transformed into the bacteria. The standard method for making the bacteria permeable to DNA involves treatment with calcium ions.
Q7. Homeostasis in the body is largely maintained by :
Answer : Option A
Explaination / Solution:
Homeostasis is the maintenance of constant body temperature. It is mainly maintained by excretion and osmoregulation, which is the function of kidney.
Q8. According to abiogenesis life originates from
Answer : Option A
Explaination / Solution:
According to abiogenesis theory of origin of life, life originated from non-living matter like gases, inorganic substance and water at particular temperature and pressure.
Q9. Sclerids belongs to
Answer : Option D
Explaination / Solution:
Scleroids belongs to sclerenchyma complex permanent tissue presentin hard parts of plants. They are generally hard and founds in rough fruits and stem.
Q10. The undifferentiated mass of parenchymatous cells are called
Answer : Option A
Explaination / Solution:
Plant callus is a growing mass of unorganized plant parenchyma cells. In living plants, callus cells are those cells that cover a plant wound.
