Q31. What is the term for the process by which plants lose water vapor through small pores on their leaves?
a) Osmosis
b) Transpiration
c) Respiration
d) Photosynthesis
Show Answer
Correct Answer: b) Transpiration
Explanation: Transpiration is the process by which plants lose water vapor through small openings called stomata on the surface of their leaves. It helps to regulate water uptake from the soil and maintain plant hydration.
Q32. Which of the following is a type of symbiotic relationship where both species benefit?
a) Mutualism
b) Parasitism
c) Commensalism
d) Predation
Show Answer
Q33. What is the term for the specific location of a gene on a chromosome?
a) Allele
b) Phenotype
c) Genotype
d) Locus
Q34. Which of the following is NOT a nitrogenous base found in DNA?
a) Adenine
b) Guanine
c) Thymine
d) Uracil
Show Answer
Correct Answer: d) Uracil
Explanation: Uracil is a nitrogenous base found in RNA but not in DNA. In DNA, the nitrogenous bases are adenine (A), cytosine (C), guanine (G), and thymine (T).
Q35. What is the term for the process by which organisms evolve similar traits due to similar environmental pressures?
a) Convergent evolution
b) Divergent evolution
c) Coevolution
d) Adaptive radiation
Show Answer
Correct Answer: a) Convergent evolution
Explanation: Convergent evolution occurs when unrelated species independently evolve similar traits in response to similar environmental pressures, resulting in analogous structures with similar functions but different evolutionary origins.
Q36. Which of the following is a nitrogenous waste product excreted by mammals?
a) Urea
b) Ammonia
c) Uric acid
d) Nitrate
Show Answer
Correct Answer: a) Urea
Explanation: Urea is the primary nitrogenous waste product excreted by mammals, including humans. It is produced in the liver from ammonia and carbon dioxide and is excreted in urine.
Q37. What is the term for the process by which plants convert nitrates into nitrogen gas, returning it to the atmosphere?
a) Nitrogen fixation
b) Nitrification
c) Denitrification
d) Ammonification
Show Answer
Correct Answer: c) Denitrification
Explanation: Denitrification is the process by which certain bacteria convert nitrates (NO3-) in the soil into nitrogen gas (N2), which is released back into the atmosphere. It completes the nitrogen cycle by returning nitrogen to its gaseous form.
Q38. Which of the following is NOT a characteristic of the kingdom Plantae?
a) Autotrophic nutrition
b) Multicellular organization
c) Cell walls made of chitin
d) Presence of chlorophyll
Show Answer
Correct Answer: c) Cell walls made of chitin
Explanation: The kingdom Plantae includes organisms that are autotrophic, multicellular, and possess cell walls made primarily of cellulose, not chitin. Chitin is found in the cell walls of fungi.
Q39. What is the term for the process by which an organism’s genetic makeup is modified by exposure to external factors?
a) Mutation
b) Adaptation
c) Gene flow
d) Epigenetics
Show Answer
Correct Answer: d) Epigenetics
Explanation: Epigenetics refers to the study of heritable changes in gene expression or cellular phenotype caused by mechanisms other than changes in the underlying DNA sequence. These changes can be influenced by environmental factors.
Q40. Which of the following is a characteristic of the kingdom Animalia?
a) Autotrophic nutrition
b) Cell walls made of cellulose
c) Heterotrophic nutrition
d) Chlorophyll for photosynthesis
Show Answer
Correct Answer: c) Heterotrophic nutrition
Explanation: The kingdom Animalia consists of multicellular, eukaryotic organisms that obtain nutrients by consuming other organisms or organic matter. They exhibit heterotrophic nutrition, in contrast to autotrophic organisms, which produce their own food.