Biology MCQs

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Nutrition is plants is classified into two main categories: autotrophic and heterotrophic. Heterotrophic plants are further classified into saprophytes, parasite and insectivores.
Saprophytes are those plants which grow and live on dead organic matter including animal and plant remains
Insectivorous plants are autotrophic but develop adaptations to trap insects in order to supplement the deficiency of Nitrogen in the soil. They feed on insects. They are generally found in nitrogen deficient habitats and hence to compensate the loss, they use insects as a source of nitrogen.

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Plasma is 55% of the blood by volume and constitutes 5% of the body weight. Plasma is a pale yellow transparent clear fluid which consists of 90-92% water and 8-10% organic and inorganic substances. Organic substances are mainly plasma proteins viz. albumin, globulin, prothrombin and fibrinogen. Albumins are responsible for maintenance of osmotic pressure of Blood. Globulins are chief sites for formation of antibodies; while prothrombin and fibrinogen are essential for clotting of blood

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Flowering in long day plants is related to Gibberlin. Long-day plants usually flower when the night length falls below their critical photoperiod. Many of our summer blooming flowers and garden vegetables are long day plants.

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Albumin is most abundant in eggs. Albumin is a family of globular proteins are water-soluble, moderately soluble in concentrated salt solutions, and experience heat denaturation. Substances which contain albumins are called albuminoids.

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This process requires that a high pressure be exerted on the high concentration side of the membrane.

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Viruses are small infectious agents that can replicate only inside the living cells of an organism. Viruses are classified based on the type of genetic material they contain. Some viruses have DNA as their genetic material, while others have RNA. Some viruses have both DNA and RNA as their genetic material.

DNA viruses have double-stranded DNA as their genetic material. They replicate their DNA using the enzymes and machinery of the host cell. Examples of DNA viruses include herpes viruses, pox viruses, and adenoviruses.

RNA viruses have single-stranded RNA as their genetic material. They replicate their RNA using the enzymes and machinery of the host cell. Examples of RNA viruses include influenza viruses, HIV, and coronaviruses.

Viruses that have both DNA and RNA as their genetic material are known as “retroviruses.” These viruses contain a single strand of RNA, but they use an enzyme called reverse transcriptase to convert their RNA into DNA. The DNA is then integrated into the host cell’s genome and replicated along with the host cell’s DNA. Examples of retroviruses include HIV and the human T-cell leukemia virus.

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Ishihara Test is used for the diagnosis of ‘Colour-Blindness’ in people. The test contains a number of colored plates, called Ishihara plates. Each of these plates contain a circle of dots appearing randomized in color and size.

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The movement of water through semipermeable membrane from region of higher concentration to region of lower concentration is called Osmosis. The uptake or absorbtion of water by solid substance without forming solution is called Imbibition.

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Mitochondrion carries on the process of cell respiration converting glucose to ATP energy the cell can use. An organelle found in large numbers in most cells, in which the biochemical processes of respiration and energy production occur. It has a double membrane, the inner part being folded inwards to form layers.

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Most accurate way to estimate tree age is to count the annual rings of wood growth. Each ring marks a complete cycle of seasons, or one year, in the tree’s life.