Biology MCQs

Notes:
Phenylketonuria (PKU) is an inborn error of metabolism due to atrophy of endocrine glands that results in decreased metabolism of the amino acid phenylalanine. Untreated, PKU can lead to intellectual disability, seizures, behavioral problems, and mental disorders. It may also result in a musty smell and lighter skin.

Notes:
• If you are colorblind, you have difficulty distinguishing certain colors, such as blue and yellow or red and green. Color blindness is an inherited condition that affects males more frequently than females
• Hemophilia A and hemophilia B are inherited in an X-linked recessive pattern. The genes associated with these conditions are located on the X chromosome, which is one of the two sex chromosomes. In females (who have two X chromosomes), a mutation would have to occur in both copies of the gene to cause the disorder.
• Sickle cell anemia is inherited as an autosomal recessive condition. This means that the gene can be passed on from a parent carrying it to male and female children.

Notes:
There are 13 essential nutrients required by plants for its healthy and proper growth. Now these nutrients are divided into two categories:
Macronutrients (nitrogen, phosphorus, potassium, calcium, magnesium and sulphur)
Micronutrients (iron, copper, manganese, zinc, boron, molybdenum and chlorine)
Additional mineral nutrient elements which are beneficial but not necessary are sodium, cobalt, vanadium, nickel, solenium, aluminium and silicon. Thus boron, zinc and copper falls into category of essential micronutrients while sodium does not.
 

Notes:
Alpha-keratin, or α-keratin, is a type of keratin found in vertebrates. This protein is the primary component in hairs, horns, mammalian claws, nails and the epidermis layer of the skin. α-keratin is a fibrous structural protein, meaning it is made up of amino acids that form a repeating secondary structure.

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Histochemistry combines the techniques of biochemistry and histology in the study of the chemical constitution of cells and tissues.

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Vitamin D was discovered by Sir Edward Mellanby.

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The change from lysogeny to lymph is usually induced by ultraviolet light. Lysogeny is a type of life cycle that occurs when a bacteriophage infects certain types of bacteria.

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Pertussis is a respiratory disease commonly known as whooping cough. It is a very contagious disease caused by a type of bacteria called Bordetella pertussis.

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The smallest gymnosperm is Zamia pygmia which reaches a height of 25 cm.

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The pericarp is a part of the fruit. Petals, Sepals, Pistil, and Stamen are parts of the flower.