Tag: science & technology

Bone marrow contains large populations of hematopoietic stem cells that continuously produce blood cells throughout life. While stem cells exist in many tissues, bone marrow is the richest source in the adult human body and is routinely harvested for medical treatments.

Chlorofluorocarbons (CFCs) release chlorine atoms in the stratosphere when broken down by UV radiation, which then catalytically destroy ozone molecules. The Montreal Protocol was established to phase out CFC production due to their severe environmental impact.

Acid rain is an environmental phenomenon caused by pollution, while photosynthesis, stomata, and carbon/oxygen cycles are all biological processes related to plants. Acid rain is the odd one out as it's harmful rather than a natural biological function.

Newton's three laws of motion describe the relationship between forces and motion (1st: inertia, 2nd: F=ma, 3rd: action-reaction). Newton's law of universal gravitation is a separate theory about gravitational attraction between masses, not part of the three laws of motion.

Different enzymes catalyze different steps of protein synthesis - aminoacyl-tRNA synthetases, peptidyl transferase, etc. There's no single enzyme responsible for the entire process. Option A correctly states that it depends on the specific protein and enzymatic step involved.

This is the law of conservation of energy - one of the fundamental principles of physics. Energy can change forms (kinetic to potential, chemical to thermal, etc.) but the total energy in a closed system remains constant - it cannot be created or destroyed.

Craig Venter was the first scientist to sequence his own complete genome through his company Celera Genomics, completing this in 2007 as part of the Human Genome Project. He pioneered shotgun sequencing techniques.

VIBGYOR represents the seven colors of the rainbow in order: Violet, Indigo, Blue, Green, Yellow, Orange, Red. Grey is not a spectral color - it's achromatic and doesn't appear in the rainbow spectrum.

Light travels at approximately 300,000 km/s. The Earth is about 150 million km from the Sun, so light takes approximately 500 seconds or 8 minutes 20 seconds to reach us. '8 minutes' is the closest correct approximation.