Explanation

• Solar power is a renewable energy source that generates electricity from sunlight.
• It does not emit carbon dioxide (CO2) or any other greenhouse gases.

The sources of carbon dioxide emissions:

• Burning of fossil fuels (such as coal, oil, and natural gas) releases CO2 into the atmosphere.
• Burning wood (such as in fireplaces or woodstoves) also releases CO2.
• Respiration (the process by which living organisms breathe) releases CO2 as a byproduct.
• Car exhaust smoke (from internal combustion engines) contains CO2, as well as other pollutants.

Explanation

• Camels have a special water storage space in their humps, which store fatty tissue.
• When food and water are scarce, the camel's body metabolizes the fatty tissue in the hump, providing energy and water.
• This allows camels to survive for extended periods without water.

Explanation

Calcium is crucial for:

• Building and maintaining strong bones and teeth
• Muscle function and contraction
• Nerve function and transmission
• Blood clotting and wound healing

Explanation

Proteins are an essential nutrient that helps our body grow and repair tissues and muscles.

They are made up of amino acids, which are the building blocks of protein.

Proteins are necessary for:

• Building and repairing muscle tissue
• Supporting growth and development
• Maintaining healthy skin, hair, and nails
• Producing enzymes and hormones

Explanation

The intensity of an earthquake is measured by the Richter scale.

It quantifies the energy released.

It was developed in 1935.

The Richter scale is used in seismology, the study of earthquakes.

Explanation

Amphoteric substances are those that can react with both acids and bases.

They can donate or accept protons (H+ ions), depending on the conditions.

Examples of amphoteric substances include water (H2O), amino acids, and certain metals like zinc and aluminum.

Explanation

• Red stars, also known as red dwarfs, typically have a surface temperature around 3000°C (5400°F).
• This is the coolest temperature range for stars, and it's what gives them their distinctive red color.

Explanation

A refracting telescope has two lenses:

1. A primary lens (objective) that collects and focuses light.
2. A secondary lens (eyepiece) that magnifies the focused light to form an image.

Explanation

• In a mercury thermometer, the mercury in the bulb expands and rises in the tube, which has a linear scale ranging from 94°F to 108°F.
• This specific range is commonly used for medical thermometers to measure human body temperature.

Explanation

• Atmospheric pressure is a scalar quantity that acts equally in all directions, pressing on surfaces from all sides.
• This is why a balloon expands in all directions when inflated, and why a submarine is squeezed from all sides by the surrounding water pressure.