Everyday Science MCQ (Multiple Choice Questions)

Correct Answer: B. 250 million years.
The time taken by the Sun to complete one revolution around the center of our galaxy is approximately 250 million years. This is known as a galactic year or cosmic year. The motion of the Sun and other stars around the center of the galaxy is due to the gravitational attraction of the massive black hole located at the center of the Milky Way. During this time, the Sun and its planets move through the spiral arms of the galaxy, experiencing various cosmic phenomena such as supernovae and cosmic rays.

Correct Answer: A. Protons.
Primary cosmic rays are composed largely of very fast-moving protons, which are high-energy particles that originate from sources outside of our solar system. These particles are accelerated to incredibly high speeds by powerful events like supernovae explosions and the accretion of matter onto black holes. When these high-energy particles collide with the Earth’s atmosphere, they create a shower of secondary particles, including muons, electrons, and gamma rays, which can be detected by ground-based instruments.

Correct Answer: A. Nuclear fusion.
The Sun produces most of its energy through the process of nuclear fusion, which occurs in its core. In this process, hydrogen atoms combine to form helium, releasing a tremendous amount of energy in the form of light and heat. This energy is what provides warmth and light to the Earth and sustains life on our planet. Nuclear fission is a different process, where an atomic nucleus is split into two smaller nuclei, releasing energy. This process is used in nuclear power plants to generate electricity, but it is not the primary source of energy for the Sun.

Correct Answer: A. Bronchiole.
Inhaled air passes through the following structures in the respiratory system: nose/mouth, pharynx, larynx, trachea, bronchi, bronchioles, and finally the alveoli, where gas exchange occurs. The bronchioles are the smallest branches of the bronchial tubes in the lungs, and they play a key role in regulating air flow and delivering air to the alveoli.

Correct Answer: C. Cornea.
In eye donation, the cornea is used for transplantation to restore vision in individuals with corneal blindness. The cornea is the clear, outermost layer of the eye that covers the iris and the pupil. It plays a vital role in focusing light that enters the eye, and any damage to the cornea can result in vision impairment or loss. Corneal transplantation involves replacing the damaged cornea with a healthy cornea from a deceased donor. The procedure is safe and effective and has restored vision in millions of people worldwide.

Correct Answer: C. hypothalamus.
The hypothalamus is a small but important part of the brain that regulates a wide range of bodily functions, including body temperature, hunger and thirst, and sleep and wake cycles. It acts as a control center, receiving signals from the body and adjusting its output accordingly to maintain homeostasis. When the body’s temperature rises or falls too far from the normal range, the hypothalamus sends signals to activate processes that either generate or release heat to bring the body back to a stable temperature.

Correct Answer: B. Bromine.
Bromine is the only non-metal that remains liquid at room temperature. It is a halogen and its atomic number is 35. It is a dense, reddish-brown liquid that evaporates easily at room temperature, giving off a red vapor that has a strong and irritating odor. It is used in the production of flame retardants, agricultural chemicals, and pharmaceuticals, among other things.

Correct Answer: A. Graphite.
Graphite is a soft, black, carbon-based mineral that is used in pencils. When graphite is mixed with clay, it forms a mixture that is used to make the “lead” in pencils. The more graphite there is in the mixture, the softer and darker the pencil lead will be. Silicon is a chemical element used in various industrial applications, such as electronics and solar cells. Charcoal is a black, carbon-based material made by burning wood in the absence of oxygen, and it is used for cooking and art. Phosphorous is a chemical element used in various industrial applications, such as fertilizers and flame retardants.

Correct answer: B. 3.
A frog heart has three chambers: two atria and one ventricle. The two atria receive oxygenated blood from the lungs and skin, and the ventricle pumps the oxygenated blood out to the body. The ventricle is partially divided by a septum, which helps to keep the oxygenated and deoxygenated blood separated to some extent. However, in frogs, there is some mixing of the two types of blood in the ventricle, which limits the efficiency of their circulatory system.

Correct Answer: D. Inability to sleep.
Insomnia is a sleep disorder characterized by difficulty falling asleep, staying asleep, or both, despite having the opportunity to do so. People with insomnia often feel tired, have low energy, and may have difficulty concentrating during the day. Insomnia can be acute, lasting for a few days or weeks, or chronic, lasting for a month or longer. It can be caused by various factors such as stress, anxiety, depression, medical conditions, and certain medications. Treatment for insomnia may include behavioral changes, therapy, and medication.