#ssc 10th
- Smoking tobacco mainly damages the Answer: B. lungs Smoking damages the lungs and can cause lung cancer and bronchitis. 1
- Cirrhosis is a disease of the liver commonly caused by Answer: C. excessive consumption of alcohol Long-term alcohol abuse damages liver cells, leading to cirrhosis. 1
- Which of the following is a geological natural disaster? Answer: A. Earthquake Earthquakes are caused by movements in the earth's crust; the others are man-made. 1
- The first aid for a minor burn is to Answer: B. pour cool clean water over the burnt area Cool running water reduces pain and damage. Do not burst blisters or apply ink. 1
- The theory of natural selection was proposed by Answer: A. Charles Darwin Charles Darwin proposed the theory of natural selection in 'On the Origin of Species'. 1
- The theory of inheritance of acquired characters was proposed by Answer: B. Lamarck Lamarck proposed that characters acquired during an organism's life are passed on to the next generation. 1
- Which of the following is a vestigial organ in human beings? Answer: A. Vermiform appendix The vermiform appendix has no useful function in humans, so it is a vestigial organ. 1
- Archaeopteryx is considered a connecting link between Answer: D. reptiles and birds Archaeopteryx had feathers and wings like birds, and teeth and a long tail like reptiles. 1
- Peripatus is a connecting link between Answer: C. annelids and arthropods Peripatus has segmented body like annelids and jointed appendages and trachea like arthropods. 1
- The process of formation of mRNA from DNA is called Answer: B. transcription The information in DNA is copied into mRNA during transcription. Protein formation from mRNA is translation. 1
- The age of fossils is commonly found by Answer: A. carbon dating using C-14 The proportion of radioactive C-14 left in the fossil is used to estimate its age. 1
- A codon on mRNA consists of Answer: C. three nucleotides Each codon is a triplet of nitrogenous bases (nucleotides) that codes for one amino acid. 1
- The duck-billed platypus is a connecting link between Answer: C. reptiles and mammals The platypus lays eggs like reptiles but has hair and mammary glands like mammals. 1
- The forelimbs of human, whale and bat are similar in structure but different in function. Such organs are called Answer: C. homologous organs Homologous organs have similar structure and origin but different functions; they show common ancestry. 1
- The flow of energy in an ecosystem is Answer: C. unidirectional Energy flows from the sun to producers and then consumers, and is lost as heat at each level; it does not return.... 1
- The book 'On the Origin of Species' was written by Answer: C. Charles Darwin Charles Darwin wrote 'On the Origin of Species' (1859). 1
- The wings of a butterfly and the wings of a bird are Answer: C. analogous organs They perform the same function (flight) but differ in structure and origin, so they are analogous. 1
- The mutation theory of evolution was proposed by Answer: D. Hugo de Vries Hugo de Vries proposed that sudden changes (mutations) lead to new species. 1
- In aerobic respiration, the final acceptor of electrons is Answer: C. oxygen In the electron transport chain, oxygen accepts electrons and combines with hydrogen to form water. 1
- Mitosis in one cell produces Answer: C. two daughter cells Mitosis gives two daughter cells with the same chromosome number as the parent cell. 1
- One gram of fat on complete oxidation gives about Answer: B. 9 kcal Fats give about 9 kcal/g, while carbohydrates and proteins give about 4 kcal/g. 1
- Bryophyllum is propagated vegetatively by its Answer: C. leaves Buds on the margins of Bryophyllum leaves grow into new plants. 1
- Pollen grains are produced in the Answer: D. anther The anther of the stamen produces pollen grains. 1
- In human beings, implantation of the embryo takes place in the Answer: B. uterus The embryo implants in the inner wall of the uterus. 1