501. The Primary Consumers are also called as

A. Herbivores
B. Carnivores
C. Enzymes
D. None of these
✅ The correct answer is option A.
Primary consumers are animals that eat primary producers; they are also called herbivores (plant-eaters). Secondary consumers eat primary consumers. They are carnivores (meat-eaters) and omnivores (animals that eat both animals and plants).

503. Black lung disease is associated with

A. Farmers
B. Coal miners
C. Textile industry workers
D. Sweepers
✅ The correct answer is option B.
Coal workers’ pneumoconiosis (CWP), also known as black lung disease or black lung, is caused by long-term exposure to coal dust. It is common in coal miners and others who work with coal. It is similar to both silicosis from inhaling silica dust and asbestos dust.

506. Producers are otherwise known as

A. Organisms
B. Manufacturers
C. Organic compounds
D. Autotrophs
✅ The correct answer is option D.
Producers are organisms that make their own food; they are also known as autotrophs. They get energy from chemicals or the sun, and with the help of water, convert that energy into usable energy in the form of sugar, or food. The most common example of a producer are plants.

507. Suppose last night was clear and calm. Tonight low clouds will be present. From this you would conclude that tonight’s minimum temperature will be:

A. Higher than last night’s minimum temperature
B. Lower than last night’s minimum temperature
C. The same as last night’s minimum temperature
D. Above freezing
✅ The correct answer is option A.
Tonight’s minimum temperature will be higher than last night’s minimum temperature.

508. Non-lonizing radiations with specific biological effects are

A. Gamma rays
B. Beta-rays
C. UV radiations
D. X-rays
✅ The correct answer is option C.
In terms of potential biological effects, the non-ionizing portion of the spectrum can be subdivided into: The optical radiation portion, where electron excitation can occur (visible light, infrared light) The portion where the wavelength is smaller than the body. Heating via induced currents can occur.