Explanation

The lifespan of a red blood cell is around 120 days.

Blood cells are made in the bone marrow.

Explanation

Nitrous oxide, commonly known as laughing gas.

It is a chemical compound, an oxide of nitrogen with the formula N. O.

At room temperature, it is a non-flammable gas, with a slight metallic scent and taste.

Explanation

The human body typically has 206 bones

At the time of birth, there are 270 bones which fuse with time to come to a total of 206 bones.

The total bones of our body can be divided into:

• the axial skeleton (80) 
• the appendicular skeleton (126)

The newborn child has 300 bones.

Longest bone: Femur (thigh bone)

Shortest: Stapes (one of the 3 small bones inside the ear)

The human head has 22 bones.

Explanation

The hardest substance in the world is diamond.

Its hardness is due to the strong covalent bonding between its carbon atoms.

This making it the most resistant to scratching.

Category: Native minerals

Cleavage: 111 (perfect in four directions)

Crystal class: Hexoctahedral (m3m); H-M symbol: (4/m 3 2/m)

Crystal habit: Octahedral

Crystal system: Cubic

Dana classification: 1.3.6.1

Density: 3.5–3.53 g/cm3 3500–3530 kg/m3

Explanation

The blue whale, a marine mammal in the suborder of baleen whales.

It is the largest known animal to have ever existed.

It measuring up to 30 meters (98 feet) in length and weighing 180 metric tons (200 short tons) or more.

Explanation

The Sun is a star.

There are lots of stars, but the Sun is the closest one to Earth.

It is the center of our solar system.

The Sun is a hot ball of glowing gases.

The sun is composed of layers made up almost entirely of hydrogen and helium.

Explanation

• Sunlight is a good source of vitamin D.
• When our skin is exposed to sunlight, it produces vitamin D, which is essential for bone health, immune function, and the regulation of calcium levels in the blood.
• Deficiency of Vitamin D results in Rickets.

Explanation

Confusion

Meteorology is a branch of the atmospheric sciences.

Metrology is the scientific study of measurement.

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Agrostology: Study of Grasses 

Agronomy: soil management and crop production 

Odontology: study of teeth 

Arthrology: Study of joints 

Nephrology: study of kidneys

Hematology: Study of blood  

Dermatology:  Study of skin

Explanation

Dry ice is a solid form of carbon dioxide.

...

"Dry ice" is solid, frozen carbon dioxide, which is sublimated at a chilly -78.5 °C (-109.3°F).

Dry ice is used primarily as a cooling agent.

Dry ice does not melt into a liquid when heated instead, it changes directly into a gas.

ND16-8-2023

Explanation

The usual gases used for lifting airships are hydrogen and helium.

Hydrogen is the lightest known gas and thus has great lifting capacity,

Helium is not as buoyant but is far safer than hydrogen because it does not burn.