Biology MCQs

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Metaxylem is the part of the primary xylem that differentiates after the protoxylem and that is distinguished typically by broader tracheids and vessels with pitted or reticulate walls.

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DPT is a class of combination vaccines against three infectious diseases in humans: diphtheria, pertussis (whooping cough), and tetanus. The vaccine components include diphtheria and tetanus and killed whole cells of the bacterium that causes pertussis. Diptheria is a highly contagious bacterial infection typically affecting the throat and tonsils with the formation of a thick grey membrane over those areas.   Tetanus is bacteria which lives in soil and contaminates wounds, where it produces a powerful toxin, the toxin attacks the nervous system causing increasing muscle spasm and rigidity. Whooping Cough is one of the most contagious bacterial infections known. Beginning with a runny nose and sore throat, it progresses to a severe spasmodic cough which persists for around 3 months.

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Bacillus Calmette Guérin or BCG is usually given around birth to prevent severe TB in infants. The neonatal immune system is immature. Delaying BCG vaccination from birth to 10 weeks of age would enhance the vaccine-induced immune response. The BCG vaccine is an injection given to children who have a higher risk of catching TB. The BCG vaccine helps your child’s immune system fight the germs that cause TB and helps stop them from getting serious TB disease.

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Spiders, mites, scorpions, and several related groups are not insects, but belong to the arthropod class Arachnida. About 15 families of spiders are frequently encountered in crops, where they provide benefit as natural control agents.

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Haemophilia is a mostly inherited genetic disorder that impairs the body’s ability to make blood clots, a process needed to stop bleeding. This results in people bleeding longer after an injury, easy bruising, and an increased risk of bleeding inside joints or the brain.

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• 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.

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Herpetology is the branch of zoology concerned with the study of amphibians (including frogs, toads, salamanders, newts and gymnophyonas) and reptiles (including snakes, lizards, amphibians, turtles, terrapins, tortoises, crocodiles and tuataras).

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Hemocoelic body cavity is a characteristic of Cockroach.

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A capsid is the protein shell of a type of virus, which encloses its genetic material.

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The common name of pteridophytes is Ferns. Ferns are vascular plants that differ from lycophytes in having true leaves that are often pinnate.