Free CELSA Knowledge Questions and Answers
Which element is known as the building block of life?
Carbon is often referred to as the building block of life due to its unparalleled ability to form stable bonds with many elements, including itself. This property allows carbon to form a diverse array of complex organic molecules, which are fundamental components of biological organisms. Carbon's versatile bonding makes it central in the chemistry of almost all living creatures and is thus critical to the study and understanding of biochemistry.
How many stripes are there on the US flag?
There are 13 stripes on the US flag. Each stripe represents one of the original 13 colonies that declared independence from Great Britain and formed the United States. The stripes alternate between red and white, with a total of seven red stripes and six white stripes. This design has been in use since 1777 when the Second Continental Congress passed the Flag Resolution, establishing the flag's design.
What is the color of blood when it's inside your body?
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The color of blood when inside the body is red. This is due to hemoglobin, a protein that binds with oxygen and gives blood its red hue. The presence of oxygenated or deoxygenated blood determines its shade of red.
Which is the fastest bird in the world?
Renowned for its remarkable flight speed, the peregrine falcon is distinguished as the fastest bird globally, capable of reaching speeds exceeding 300 km (186 miles) per hour during dives. This exceptional velocity also earns it the title of the fastest animal on Earth.
What is the capital city if Canada?
Ottawa is the capital city of Canada. It is located in the province of Ontario and serves as the political center of the country, hosting the federal government, including Parliament Hill. Toronto, while being the largest city and a financial hub, is not the capital. Similarly, Vancouver and Montreal are major cities in Canada but do not serve as the capital.
About how many scents can a human nose remember?
The human nose is capable of remembering around 50,000 scents. This is due to the olfactory system, which is responsible for our sense of smell. The olfactory system contains millions of olfactory receptors that can detect different scents. These receptors send signals to the brain, remember such a large number of scents is impressive and highlights the complexity and sensitivity of the human sense of smell.
Which ancient civilization is credited with the invention of wheel?
The Sumerians, an ancient civilization that flourished in Mesopotamia, are credited with the invention of the wheel around 3500 B.C. This innovation greatly facilitated transportation and trade for ancient societies by allowing the construction of wheeled vehicles, which could carry heavy loads over long distances more efficiently than previously possible.
What was the main purpose of the pyramids built by the ancient Egyptians?
The pyramids of ancient Egypt were monumental structures built primarily as tombs for the country's pharaohs and their consorts. The most famous pyramid complex, which includes the Great Pyramid of Giza, highlights this function. These massive architectural feats were intended to protect the deceased and their belongings and to celebrate the pharaohs' life and afterlife, according to Egyptian religious beliefs.
What is the tallest waterfall in the world?
The tallest waterfall in the world is Angel Falls in Venezuela. With a height of 3,212 feet (979 meters) and continuous drop, Angel Falls holds the title as the highest waterfall on the planet.
Which food item never spoils?
Honey never spoils because it has a very low moisture content and high acidity level, which creates an inhospitable environment for bacteria and other microorganisms to grow. Additionally, honey contains natural preservatives such as hydrogen peroxide and high sugar content, which further inhibit the growth of bacteria and spoilage. These factors make honey an extremely shelf-stable food that can last indefinitely if stored properly.
Which planet is known as the "Red Planet"?
Mars is commonly referred to as the "Red Planet" due to its reddish appearance, which is visible from Earth. This characteristic color comes from iron oxide, or rust that covers much of the planet's surface. Mars' distinct hue makes it visually distinctive object in the night sky and has also influenced a significant amount of scientific research focused on its geology and potential for supporting life.