Biology MCQs

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Green diesel is also a type of biofuel, produced by hydrocarbon oil and fat feedstock. Bio-ethers and Re-formulated gasoline are also a type of biofuels.

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Bt cotton is a transgenic plant. Plants in which one or more genes of another species have been introduced into the genome using genetic engineering procedures are called transgenic plants.

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The nitrogen-fixing capability of Azolla an aquatic pteridophyte has led to it being widely used as a biofertiliser for increasing the productivity of rice fields. When rice paddies are flooded in the spring, they can be inoculated with Azolla, which then quickly multiplies to cover the water, suppressing weeds. The rotting plant material releases nitrogen to the rice plants, increasing the rice yield equivalent to that produced by 30-60 kg N/ha.

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Solitary cymose inflorescence refers to a determinate inflorescence composed of a single flower. Examples include poppy, gardenia (ornamental plant), tulip, etc. Flowers are said to be solitary when the plant bears only one, or when single flowers appear on the ends of lateral branches that are remote from one another.

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Prokaryotic cells do not contain a nucleus or any other membrane-bound organelle. The word “prokaryotic” means “before nucleus.” Prokaryotes include two groups: bacteria and another group called archaea. In contrast, eukaryotic cells have a “true” nucleus containing their DNA.

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A wisdom tooth, in humans, is any of the usual four third molars. Wisdom teeth usually appear between the ages of 16 and 25. They are generally thought to be called wisdom teeth because they appear so late – much later than the other teeth, at an age where people are presumably “wiser” than as a child, when the other teeth erupt.

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The life span of a parrot depends on the species. Smaller types of parrots generally have a life span of 15 to 20 years, while some larger varieties can live up to 120 years. The amount of time that a parrot lives greatly depends on its species, level of care, and overall health. It is not a rare occurrence for a pet parrot to outlive its owner.

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Liver produces bile which is stored in the gall bladder. Liver is the largest gland in the body. Bite contains bite pigments and bite salts i.e. sodium and potassium glycocholates.

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A Barr body is the inactive X chromosome in a female somatic cell in those species in which sex is determined by the presence of the Y or W chromosome rather than the diploidy of the X or Z. A typical human female has only one Barr body per somatic cell, while a typical human male has none.

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Evolutionary biologists classify tailbone as vestigial organs, or body parts that have become functionless due to evolution. It is perhaps the most commonly touted example in man of a “useless” evolutionary vestige. Also known as coccyx (because of its similarity to the shape of a cuckoo’s beak), tailbone is a vestigial tail left over from our tailed monkey- like ancestors.