Explanation

A nucleotide, the building block of DNA and RNA, consists of three components:

1. A phosphate group (phosphate)
2. A sugar molecule (deoxyribose in DNA and ribose in RNA)
3. One of four nitrogenous bases (Adenine, Guanine, Cytosine, and Thymine in DNA; Adenine, Guanine, Cytosine, and Uracil in RNA)

Explanation

The structure of the brain is similar to the structure of a Walnut, with both having:

• A hard outer layer (cranium vs. shell)
• A wrinkled surface (brain's cerebral cortex vs. walnut's surface)
• A distinct left and right half (brain's hemispheres vs. walnut's halves)

Explanation

• Deforestation is the permanent destruction of forests to make the land available for other uses.
• Such as agriculture, urbanization, and logging.

Explanation

• Venera-9 was the first spacecraft to land on the surface of Venus.
• Launched by the Soviet Union in 1975.
• It was designed to study the Venusian atmosphere and surface.
• It successfully transmitted data from the planet's surface for 53 minutes before its batteries failed.

Explanation

• The optical centre is the point within a lens where a ray of light passes through without changing its direction or path.
• This point is located at the centre of the lens, on the optical axis.

Explanation

• The pressure exerted by a liquid at a given point increases with the depth of the liquid, as the weight of the liquid above increases.
• This is described by Pascal's Law, which states that the pressure at a point in a fluid is proportional to the depth of the fluid.

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

• Measurement involves comparing an unknown quantity (the measured) with a standard quantity (the unit) to determine its value.
• This process is a fundamental aspect of science and engineering, allowing us to quantify physical properties and phenomena.

Explanation

The correct order from least to most acidic:

• Ammonia (pH 11-12, strongly basic)
• Blood (pH 7.4, slightly basic)
• Milk (pH 6.5-7, slightly acidic)
• Orange juice (pH 3.5-4.5, strongly acidic)

Explanation

• The products in the reaction are Carbon dioxide (CO2) and Water (H2O).
• These products are formed through the combustion of Methane (CH4) and Oxygen (O2), releasing energy in the process.