Physics Chemistry & Biology Test 7
Which gas is essential for respiration ?
Explanation: Oxygen is vital for respiration, the process where living organisms break down food molecules to release energy. It helps produce ATP, the main energy source in body cells.
Which planet is known as the “Morning Star” ?
Explanation: Venus appears bright before sunrise and after sunset, so it’s called the Morning Star or Evening Star. It reflects sunlight strongly due to its thick cloudy atmosphere.
Which part of the cell controls all its activities ?
Explanation: The nucleus is the control center of the cell. It contains DNA, which stores genetic information and directs cell growth, division, and protein synthesis.
What is the chemical formula of water ?
Explanation: Water’s chemical formula H₂O means it has two hydrogen atoms and one oxygen atom. It’s essential for life processes, temperature regulation, and chemical reactions in all organisms.
Which gas is essential for photosynthesis ?
Explanation: Plants use carbon dioxide during photosynthesis to produce glucose and oxygen. With the help of sunlight and chlorophyll, CO₂ combines with water to make food for the plant.
What is the SI unit of force ?
Explanation: The SI unit of force is the Newton (N), named after Sir Isaac Newton. One Newton equals the force required to accelerate a 1 kg mass by 1 m/s².
Which part of the human body controls balance ?