Class 12 Biology MCQ

1. Which term refers to the variety and variability of life on Earth? a) Ecosystem b) Biogeography c) Biodiversity d) Speciation Click to View Answer and Explanation Answer: c) Biodiversity Explanation: Biodiversity encompasses the range of variation among living organisms from all sources, including terrestrial, marine, and other ecosystems. 2. Which of the following is […]

1. Which component of an ecosystem includes living organisms? a) Abiotic b) Biotic c) Decomposers d) Producers Click to View Answer and Explanation Answer: b) Biotic Explanation: The biotic component of an ecosystem includes all living organisms, from plants to animals to microorganisms. 2. What are the primary producers in a pond ecosystem? a) Fishes

1. Which of the following is NOT an abiotic factor in an ecosystem? a) Temperature b) Soil c) Bacteria d) Light Click to View Answer and Explanation Answer: c) Bacteria Explanation: Bacteria are living organisms and therefore are considered biotic factors in an ecosystem. 2. The phenomenon where some organisms suspend their metabolic activities during

1. Which of the following is NOT an application of biotechnology? a) Producing synthetic polymers b) Genetically modified crops c) Gene therapy d) Biofuel production Click to View Answer and Explanation Answer: a) Producing synthetic polymers Explanation: While synthetic polymers have numerous applications, their production is not directly linked to biotechnology. 2. Bt cotton is

1. Which enzyme is used to join two pieces of DNA? a) DNA ligase b) Helicase c) DNA polymerase d) Restriction enzyme Click to View Answer and Explanation Answer: a) DNA ligase Explanation: DNA ligase facilitates the joining of DNA strands by forming phosphodiester bonds. 2. Which organism is most commonly used as a host

1. Which of the following microbes is used in the production of bread? a) Saccharomyces cerevisiae b) Lactobacillus c) Acetobacter d) Pseudomonas Click to View Answer and Explanation Answer: a) Saccharomyces cerevisiae Explanation: Saccharomyces cerevisiae, commonly known as baker's yeast, is used for fermenting the dough in bread-making. 2. The process of converting milk into

1. Which method involves the crossing of two genetically different individuals for improvement? a) Hybridization b) Mutation c) Parthenogenesis d) Cloning Click to View Answer and Explanation Answer: a) Hybridization Explanation: Hybridization is the process of crossing two genetically different individuals to combine the best traits of both. 2. The Green Revolution in India primarily

1. Who is often referred to as the father of the theory of evolution by natural selection? a) Isaac Newton b) Gregor Mendel c) Charles Darwin d) Albert Einstein Click to View Answer and Explanation Answer: c) Charles Darwin Explanation: Charles Darwin, along with Alfred Russel Wallace, proposed the theory of evolution by natural selection.

1. Which cells in the human body are primarily responsible for immune response? a) Neurons b) Red Blood Cells c) White Blood Cells d) Muscle Cells Click to View Answer and Explanation Answer: c) White Blood Cells Explanation: White Blood Cells, or leukocytes, play a vital role in defending the body against pathogens and foreign

1. Who were the scientists credited with the discovery of the structure of DNA? a) Watson and Crick b) Mendel and Morgan c) Chargaff and Franklin d) Beadle and Tatum Click to View Answer and Explanation Answer: a) Watson and Crick Explanation: James Watson and Francis Crick are credited with proposing the double helical structure

1. Who is considered the "Father of Genetics"? a) Charles Darwin b) Gregor Mendel c) James Watson d) Rosalind Franklin Click to View Answer and Explanation Answer: b) Gregor Mendel Explanation: Gregor Mendel's pioneering work with pea plants laid the groundwork for the field of genetics. 2. Which law states that alleles segregate independently of

1. The human male reproductive system includes which of the following glands? a) Thyroid b) Pancreas c) Prostate d) Adrenal Click to View Answer and Explanation Answer: c) Prostate Explanation: The prostate is a part of the male reproductive system and secretes a fluid component of semen. 2. Which stage of development implants itself into

1. Which part of a flower matures into a fruit? a) Ovary b) Stamen c) Petal d) Sepal Click to View Answer and Explanation Answer: a) Ovary Explanation: After fertilization, the ovary of the flower develops into a fruit. 2. The transfer of pollen from an anther to a stigma is called: a) Fertilization b)

1. Which type of reproduction involves only one parent and gives rise to offspring identical to the parent? a) Sexual reproduction b) Fragmentation c) Budding d) Asexual reproduction Click to View Answer and Explanation Answer: d) Asexual reproduction Explanation: Asexual reproduction involves only one parent and produces offspring that are genetically identical to the parent.