Biology MCQs

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Ductless glands which are also known as internally secreting glands or endocrine glands secrete their products or hormones directly into the blood stream in response to instructions from the brain.

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The corpus luteum is a hormone-secreting structure that forms in the ovary after an egg has been released during ovulation. It is made up of cells that were part of the follicle that contained the egg, and it produces the hormones progesterone and estrogen, which help to support pregnancy. The corpus luteum is important for maintaining the lining of the uterus and preparing the body for pregnancy. If pregnancy does not occur, the corpus luteum will break down and be absorbed by the body.

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The lungs serve to exchange the two gases in the blood. Oxygen enters the blood from the lungs and carbon dioxide is expelled out of the blood into the lungs. The blood serves to transport both gases. Oxygen is carried to the cells and tissues.

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Vitamin B9 is also called as the folic acid. Folic acid is converted into folate in the human body. Folate is essential for making DNA and RNA.
Extra info: Folic acid /B9 is recommended to the pregnants to reduce the risk of Neural Tube Defects in the foetus.

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In biology, a scheme of classifying organisms into six kingdoms: Proposed by Carl Woese et al: Animalia, Plantae, Fungi, Protista, Archaea/Archaeabacteria, and Bacteria/Eubacteria.

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Those organisms which can live on both land and water are called amphibians. Some examples of amphibians are frogs and toads, newts, salamanders and caecilians.

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Nostoc, also known as star jelly, troll’s butter, witch’s butter, and witch’s jelly, is a genus of cyanobacteria. Nostoc does not have a nuclear membrane. This is a characteristic of prokaryotic cells, which lack a nucleus. The genetic material in these cells is found in the cytoplasm, not enclosed within a nuclear membrane. On the contrary, Volvox, Agaricus, and Penicillium are all eukaryotic organisms, hence possess a nuclear membrane.

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An anticodon is found at one end of the transfer RNA (tRNA) molecule. During protein synthesis, each time an amino acid is added to the growing protein. A tRNA forms base pairs with its complementary sequence on the mRNA molecule and ensures that the appropriate amino acid is inserted into the protein.

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Fertilization is a process of sexual reproduction, which is followed by pollination and germination. Porogamy, Chalazogamy, and Mesogamy are types of fertilization.

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Fruits are fleshy substances that usually surround the seeds. Flowers help in seed dispersal.