Biology - Online Test
Q1. Main function of lenticel is
Answer : Option C
Explaination / Solution:
Lenticels are minute pore in stems through which exchange of gases takes place between plant and atmosphere.
Q2. Seed dispersal helps the species to
Answer : Option A
Explaination / Solution:
Seeds have adaptive strategies for dispersal to new habitat and help the species to colonies in new areas. Dispersal may occurs physically or with the help of birds and other animals.
Q3. Unit of evolution and ecology is
Answer : Option B
Explaination / Solution:
The unit of evolution and ecology is population. Evolution occurs due to change in genome of individual that affects the whole population. Ecology is the study of population along with their variation in ecosystem.
Q4. It is the technique of growing plants in above-ground strands provided with fine mist of normal solution.
Answer : Option B
Explaination / Solution:
Aeroponics is the technique of growing plants in above ground strands provided with fine mist of normal solution. It is used to know the deficiency symptoms of minerals.
Q5.
Match the following:
| Digestive Disorder | Cause |
| a) Constipation | i) gallstones |
| b) Jaundice | ii) reflex actionanxiety |
| c) Indigestion | iii) intentinal ischemia |
| d) Vomiting | iv) irregular bowel movements |
Answer : Option D
Explaination / Solution:
The causes of indigestion are inadequate enzyme secretion, anxiety, food poisoning, over eating, and spicy food. In constipation, the bowel movements occur irregularly. In jaundice, deposition of bile pigments result in gall stones. A reflex action is controlled by the vomit centre in the medulla.
Q6. Statement I: Asexual reproduction involves fusion of gametes.
Statement II: Asexually produced offspring are genetically identical.
Statement III: Asexual reproduction occurs in unfavorable condition only.
Statement II: Asexually produced offspring are genetically identical.
Statement III: Asexual reproduction occurs in unfavorable condition only.
Answer : Option B
Explaination / Solution:
In asexual reproduction, fusion of gametes do not takes place and asexual reproduction occurs in favorable conditions. As fusion of gametes do not takes place, all the individuals are genetically identical to each other.
Q7. Assertion: Mast cells in the human body release excessive amounts of inflammatory chemicals, which cause allergic reactions.
Reason: Allergens in the environment on reaching human body stimulate mast cells in certain individuals.
Reason: Allergens in the environment on reaching human body stimulate mast cells in certain individuals.
Answer : Option C
Explaination / Solution:
The IgE-primed mast cell releases granules and powerful chemical mediators, such as histamine, cytokines, granulocyte macrophage colony-stimulating factor (GM-CSF), leukotrienes, heparin, and many proteases into the environment. These chemical mediators cause the characteristic symptoms of allergy.
Q8. The organelle involved in respiration is
Answer : Option A
Explaination / Solution:
Mitochondria are the sites of aerobic respiration. They produce cellular energy in the form of ATP
Q9. Which one represents the correct manner of DNA replication?
Answer : Option A
Explaination / Solution:
During replication of DNA, in one strand (3’ to 5’) replication takes place continuously and in other strand it is in small segment and joined together by DNA ligase enzyme.
Q10. In photosynthesis photolysis of water is used in
Answer : Option D
Explaination / Solution:
Breaking down of water molecules in presence of sunlight during photosynthesis is called photolysis of water. During photolysis of water reduction of NADP+ into NADPH takes place.
