Biology - Online Test
Q1. One of the free-living anaerobic nitrogen-fixer is
Answer : Option B
Explaination / Solution:
Rhodospirillum is a free living anaerobic nitrogen-fixer. Rhizobium lives as symbiotic with leguminous plants and Azotobacter and Beijerinckia are symbiotic nitrogen fixer.
Q2. The list of risk factors associated with hypertension doesn’t include :
Answer : Option A
Explaination / Solution:
Hypertension can cause a number of effects on the functioning of different vital functions but hypertension does not associated with hypoglycemia and diabetes insipidus.
Q3. Fermentation is
Answer : Option C
Explaination / Solution:
Fermentation is the process of anaerobic respiration in which incomplete oxidation leads to formation of ethanol in absence of oxygen. Fermentation occurs in yeast.
Q4. Fertilizers will not
Answer : Option A
Explaination / Solution:
Fertilizers will increase the fertility of soil and higher production of crop. When reaches to water bodies it causes eutrophication. The chemicals present in it also pollute the water. Fertilizer never acts as biological control against harmful organisms.
Q5. The sexual reproduction involves fusion of special type of cells called gametes, produced by
Answer : Option D
Explaination / Solution:
Meiosis cell division is involved in gametes formation as gametes contain half the number of chromosomes that a normal cell diploid cell contains. Gametes fuse to produce diploid zygote .
Q6. DNA fragments move at different distances in Gel Electrophoresis because
Answer : Option C
Explaination / Solution:
Gel electrophoresis is a technique used to separate DNA fragments (or other macromolecules, such as RNA and proteins) based on their size and charge. Electrophoresis involves running a current through a gel containing the molecules of interest. Based on their size and charge, the molecules will travel through the gel in different directions or at different speeds, allowing them to be separated from one another.
During gel electrophoresis different fragments move at different distances due to difference in their molecular weight of the fragments. Smaller fragments move more towards anode.
Q7.
Read the following :
i. Avian kidneys have very short loops of Henle.
ii. Birds are unable to make urine as hypotonic as mammals can.
Answer : Option A
Explaination / Solution:
Avian kidneys have very short loops of Henle’s. Loops of Henle’s used in concentration of urine. Birds make urine highly hypotonic.
Q8. Assertion: Coacervates are believed to be the precursors of life.
Reason: Coacervates were self-duplicating aggregates of proteins surrounded by lipid molecules.
Reason: Coacervates were self-duplicating aggregates of proteins surrounded by lipid molecules.
Answer : Option C
Explaination / Solution:
Coacervates are believed to be the precursors of life. These molecules consists protein along with lipids. They are aggregates of proteins surrounded by lipid but self-duplicating ability were not present in them.
Q9. In acropetal succession of an inflorescence, the position of youngest floral bud is at
Answer : Option B
Explaination / Solution:
In acropetal succession of an inflorescence, the youngest floral buds are found at distal end and the oldest flower are found at proximal end.
Q10. Anatomy of stem differ from root in
Answer : Option B
Explaination / Solution:
The stem shows the epidermis covered with a thin layer of cuticle, narrow cuticle and each vascular bundle is conjoint, open and is endarch protoxylem.
