Biology - Online Test
Q1. The seeds dispersed by wind must not be
Answer : Option D
Explaination / Solution:
Dispersal of seed is necessary for proper growth of seed. The seeds located close to each other may have struggle for existence. The wind dispersed must be light, minute and winged so that it can be carried by wind easily. Sticky seeds remain attached with each other.
Q2. Among hydrophytes which of the following xylem component remains absent?
Answer : Option D
Explaination / Solution:
Xylem vessels are responsible of water transportation in plants. Hydrophytes grows in plants therefore there is no requirement of special water transporting tissues in hydrophytes.4
Q3. Dark brown amorphous substance formed by degradation of cellulose and lignin in the soil to increase water holding capacity and aeration is
Answer : Option A
Explaination / Solution:
Dark brown amorphous substance formed by degradation of cellulose and lignin in the soil to increase water holding capacity and aeration is humus. It also increase fertility of the soil.
Q4. If an imaginary food contains 5 grams of protein, 4 grams of fat and 10 grams of carbohydrates. Now calculate total calories it would provide ( given 1g protein=4 calories, 1g fat = 10 calories, 1g carbohydrates = 4 calories ) :
Answer : Option B
Explaination / Solution:
Five gram of protein will produce 5 x 4 = 20 calories, 4 g of fat = 4 x 10 = 40 calories and 10 g of carbohydrates = 10 x 4 = 40 calories. So total energy produced is equal to 20 + 40 + 40 = 100 calories.
Q5. Use of anti-histamines and steroids give a quick relief from
Answer : Option B
Explaination / Solution:
Anti-histamines and steroids give a quick relief from allergy. Allergy may be due to allergen like pollen grains, dust or other microbes. Common symptom of allergy is inflammation on skin.
Q6.
Read the following :
i. insects have taste receptors on their feets.
ii. crickets have ears on the legs.
iii. snakes are highly sensitive to air borne sounds.
iv. frogs have colour vision.
Answer : Option D
Explaination / Solution:
Insects have taste receptors on their feets.These receptor are located at different regions to get stimulus more accurately.
Crickets have ears on the legs and frogs have colour vision.
Q7. Which plant has fungal association in the form of mycorrhiza?
Answer : Option C
Explaination / Solution:
Roots in some genera of gymnosperms have fungal association in the form of mycorrhiza(Pinus).
Q8. The ribosomes of a polysome translate
Answer : Option C
Explaination / Solution:
Several ribosomes may attach to a single mRNA and form a chain called polyribosomes or polysome. The ribosomes of a polysome translate the mRNA into proteins.
Q9. What is called Griffith effect?
Answer : Option C
Explaination / Solution:
Griffith's experiment, was an experiment done in 1928 by Frederick Griffith. It was one of the first experiments showing that bacteria can get DNA through a process called transformation.
Griffith carried out experiment on mice using pneumonia causing bacteria to show that DNA is the genetic material by transforming non-virulent strain into virulent strain which is called bacterial transformation.
Q10. Carbon dioxide is fixed in
Answer : Option B
Explaination / Solution:
Photosynthesis occurs in two steps- light reaction and dark reaction. During light reaction ATP and NADPH molecules are formed and in dark reaction carbon dioxide is fixed.
