Biology MCQs

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The pylorus is the furthest part of the stomach that connects to the duodenum. It is divided into two parts, the antrum and the pyloric canal. The antrum connects to the body of the stomach, and the pyloric canal connects to the duodenum.

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Pink eye or Conjunctivitis is an irritation or inflammation of the conjunctiva, which covers the white part of the eyeball. It can be caused by allergies or a bacterial or viral infection.

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Maximum Proteins part of our food are digested in stomach and duodenum part of small intestine. Enzyme pepsin is secreted in the stomach and trypsin, chymotrypsin, and carboxypeptidase are secreted from the pancreas for digestion of protein.

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Britain is the first country to issue research licenses for human embryonic cloning to create stem cells. The cloning procedure involves the process of combining a patient’s body cell with an unfertilized egg cell from a donor.

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Alonsoa grandiflora is an ornamental plant

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Defensin-1 is the name of a protein, which has the property of resistance of epithelial surfaces to microbial colonization. This protein has the potential to develop drugs for antibiotic resistant bacteria. Honey bees make this protein and adds to honey and the scientists at the Academic Medical Centre, Amsterdam say that one day the drugs developed by Honey containing Defensin-1 , could combat antibiotic-resistant infections.

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The Coral Reef ecosystem showcases the highest biodiversity among the options provided. This is due to the ideal tropical environment in which they exist, offering a wide range of habitats, shelter, and nourishment for an astonishing array of marine life. In terms of biodiversity, they are second only to tropical rainforests. Interestingly, despite covering less than 1% of the ocean floor, coral reefs support about 25% of all known marine species.

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The most primitive life forms on Earth are prokaryotes, which are the simplest cellular forms of life. Prokaryotes include archaea and bacteria, which have been found on Earth for 3.5 to 3.8 billion years.
The earliest known life forms on Earth are fossilized microorganisms found in hydrothermal vent precipitates. These microorganisms are believed to be about 3.42 billion years old.
The first life forms were probably a tiny bacteria called archaebacteria. These bacteria thrive in very hot, chemically rich places.

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Mitochondria, Chloroplasts, Golgi Bodies, Lysosomes, Endoplasmic reticulum and Peroxisomes are absent in prokaryotic cells. Ribosomes are smaller in prokaryotic cells and larger in eukaryotic cells.

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Peepal tree has the capability to absorb CO² at night due to Crassulacean Acid Metabolism (CAM). It’s a photosynthesis pathway primarily found in desert plants and epiphytes (those that live on larger trees). During the day, CAM plants break down the malate created at night and use the released CO² to create sugars, similar to C3 plants. But, CAM, being energy inefficient, is used only under certain conditions. It seems that peepal trees use CAM when they are epiphytic and switch to C3 photosynthesis when they settle in the soil.