Biology - Online Test
Q1. Cardiac muscles are
Answer : Option A
Explaination / Solution:
Cardiac muscle tissue is a contractile tissue present only in the heart. The cardiac muscle fibres are elongated, branched and uninucleate. They appear striated due to the presence of alternate light and dark band. Cardiac muscles are self-contracting and involuntary in nature. They contract in rythmic fashion and help the heart to pump the blood.
Q2. The blue-green algae are also referred as
Answer : Option D
Explaination / Solution:
Blue green algae are also called as cyanobacteria. They are considered as most primitive organism that still survives. It includes different forms of unicellular and multicellular organisms.
Q3. If an endosperm cell of angiosperm contain 24 chromosome, the number of chromosome in each cell of root is
Answer : Option C
Explaination / Solution:
Endosperm cells are triploid as they are formed by triple fission of two polar nuclei and one male gamete. So, haploid cell will contain 8 chromosomes only. Root cells are diploid. Hence root cell will contain 16 chromosomes.
Q4. An example of predation is
Answer : Option C
Explaination / Solution:
Biological control method adopted in agricultural pest control are based on the ability of predator to regulate prey population.
Q5. Analysis of xylem sap shows
Answer : Option A
Explaination / Solution:
Mineral salts are translocated through xylem along with the ascending stream of water, which is pulled up through the plant by transpirational pull.
Q6. Active form of Which enzyme hydrolyses milk protein in stomach?
Answer : Option B
Explaination / Solution:
Rennin is a proteolytic enzyme found in gastric juice of infants which helps in the digestion of milk proteins.
Q7. AIDS can be transmitted by
Answer : Option C
Explaination / Solution:
AIDS can be transmitted from infected person to healthy person through blood transfusion. The most common way of transmission of AIDS is during sexual intercourse with multiple partners without protection.
Q8. Sneha ceased to get smell of a perfume applied to her clothes but her friend Reema who passed by complimented her for the noticeable fragrance. This is an example of :
Answer : Option C
Explaination / Solution:
The sensory organs detect all types of changes in the environment and send appropriate signals to the CNS, where all the inputs are processed and analysed.
Q9. Bryophytes flourish is moist and shady environments because
Answer : Option D
Explaination / Solution:
These plants can live in soil but are dependent on water for sexual reproduction as they release antherozoids into water where they come in contact with archegonium to produce zygote. They usually occur in damp, humid and shaded localities.
Q10. The eukaryotic ribosomes are of
Answer : Option D
Explaination / Solution:
The eukaryotic ribosomes are 80S while the prokaryotic ribosomes are 70S. Here ‘S’ stands for the sedimentation coefficient; it indirectly is a measure of density and size.
