Biology - Online Test
Q1. Brain stem is the support system of brain and is the collective name for :
Answer : Option B
Explaination / Solution:
The brainstem (or brain stem) is the posterior part of the brain, adjoining and structurally continuous with the spinal cord. In the human brain the brainstem includes the midbrain, the pons, and the medulla oblongata. Sometimes the diencephalon, the caudal part of the forebrain, is included.
Q2. Angiosperm: roots :: Phaeophyceae:
Answer : Option B
Explaination / Solution:
The plant body of phaeophyceae is usually attached to the substratum by a holdfast whereas the angiosperms attach to the substratum with the help of roots.
Q3. Which is common in plant and animal cells
Answer : Option B
Explaination / Solution:
Mitochondria are present in both plant as well as animal cells. Plastids and central vacuoles are present in plant cells and centrioles are present in only animal cells.
Q4. DNA is made of two chains that twist about one another in the shape of a
Answer : Option C
Explaination / Solution:
Double helix is the description of the structure of a DNA molecule. A DNA molecule consists of two strands that wind around each other like a twisted ladder. Each strand has a backbone made of alternating groups of sugar (deoxyribose) and phosphate groups.
Q5. Term ecosystem was introduced by :
Answer : Option A
Explaination / Solution:
The term "ecosystem" was first used in 1935 in a publication by British ecologist Arthur Tansley.
Tansley devised the concept to draw attention to the importance of transfers of materials between organisms and their environment.
Ecosystem is the functional unit of nature where living and non-living components interact with each other.
Q6. Photosynthesis is maximum in
Answer : Option C
Explaination / Solution:
There is maximum absorption by chlorophyll a, in the red region and so there is higher rate of photosynthesis.
Q7. The value of TV is about 500 ml for an average adult human male but only some part of it enters lung alveoli and rest of it fills respiratory passage. What should be the distribution ratio for alveolar volume /respiratory passage volume:
Answer : Option C
Explaination / Solution:
Tidal volume (TV) = volume moved in one breath. Normal = 500 ml
- About 70% of TV reaches alveoli (350 ml) Only this amount is involved in gas exchange
- 30% in airways =respiratory passage (anatomical dead space)
So ratio = 350:150= 7:3
Q8. Picking up plants with superior phenotype for further propagation is
Answer : Option A
Explaination / Solution:
Mass selection is a simplest , common and oldest method of crop improvement, in which large number of plants of similar superior phenotype are selected and their seeds are harvested and mixed together to constitute the new variety.
Q9. Which article of the Constitution of India specifies that, "it shall be the duty of every citizen of India to protect and improve the natural environment including forests, lakes, rivers, and wildlife and to have compassion for living creatures."
Answer : Option B
Explaination / Solution:
All the fundamental duties are contained in Art. 51A.
to protect and improve the natural environment including forests, lakes, rivers, and wildlife and to have compassion for living creatures is a fundamental duty listed in constitution of India.
Q10. The largest phylum of kingdom animalia is
Answer : Option A
Explaination / Solution:
Arthropoda is the largest phylum of kingdom animalia. It includes all insects, arachnids, myriapods and crustaceans. They are characterized by jointed limbs and cuticles.
