General Science Mixed Quiz: Set 209

The Kelvin and Fahrenheit scales read the same at about 574.25, which is about 301 degrees Celsius. The scales are linked by K = C + 273 and F = (9/5)C + 32.

The epidemic of the 1840s destroyed the potato crop of Ireland and brought on the famine, and the study of that outbreak by Anton de Bary established plant pathology as a science.

The speed of light in a medium is inversely proportional to its refractive index, so the ratio of speeds is the inverse ratio of the refractive indices.

Codex Alimentarius is Latin for food code, and the Commission of that name draws up model standards, codes of practice, and limits for additives, contaminants and pesticide residues, which member countries use when writing their own food law and which serve as the reference in international food trade.

The resistance of a conductor depends on its material and shape, not on how much current flows through it. For a cylindrical conductor, R = ρL/A, where ρ is the resistivity of the material, L the length and A the area of cross-section.

The correct answer is B, Jharkhand, the leading lac producing state of India, which also explains why the country's lac research institute stands at Namkum near Ranchi.

Lead nitrate decomposes on heating into lead(II) oxide, nitrogen dioxide and oxygen. The balanced equation is 2Pb(NO3)2 → 2PbO + 4NO2 + O2.

Egg white is mostly water and protein, and heat denatures these proteins so that they set into an opaque white solid.

Bacteria on the floor break down the urea in urine and release ammonia, which has a sharp, pungent smell. Urea, CO(NH2)2, is the main nitrogenous waste of humans.

Insulin is a protein (peptide) hormone made in the human body by the beta cells of the islets of Langerhans in the pancreas.

Sclerenchyma cells lay down thick walls hardened with lignin, and once the wall is complete the protoplasm dies. Sclerenchyma is the plant tissue that gives strength and rigidity.

The liver needs vitamin K to make prothrombin and other clotting factors, so without it blood takes much longer to clot.

It binds oxygen at its iron-containing haem groups and carries some carbon dioxide on its protein chains. Each haemoglobin molecule has four polypeptide chains and four haem groups, and each haem iron can hold one oxygen molecule, forming oxyhaemoglobin in the lungs.

Four species of Plasmodium commonly infect human beings, of which Plasmodium falciparum is the most dangerous and Plasmodium vivax the most widespread in India.

Hallucinations, most often hearing voices that others cannot hear, are a core symptom of schizophrenia. Schizophrenia is a serious mental disorder in which a person loses touch with reality.

He held that an organ used often becomes stronger and one left unused withers, and that characters so acquired in a lifetime are passed to the offspring, the giraffe's lengthening neck being his best known illustration.

Female Anopheles mosquitoes bite humans because they need blood to mature their eggs, and the malaria parasite can cross the placenta.

Lateral meristems divide along the sides of the stem and root and add new cells that make them thicker. Meristems are groups of cells that keep dividing.

The Hardy-Weinberg principle states the opposite: allele frequencies in a population stay stable, that is constant, from generation to generation.

Light passes through the condenser to the specimen, is picked up by the objective lens, travels up the body tube and reaches the eye through the eyepiece.