The question asks for the primary reason organisms respire. Respiration is a fundamental biological process essential for life. We need to identify its main purpose among the given options.
C) To release energy from food. Cellular respiration is the metabolic process that converts biochemical energy from nutrients into adenosine triphosphate (ATP), and then releases waste products. This ATP is the energy currency that powers all cellular activities, including growth, repair, movement, and reproduction.
The question asks to identify an example of anaerobic respiration. We need to understand the definition of anaerobic respiration and differentiate it from aerobic respiration and other respiratory processes.
B) Breakdown of glucose without using oxygen — This is the defining characteristic of anaerobic respiration, where energy is released from glucose in the absence of oxygen.
The question asks for the typical breathing rate of an adult human when at rest. This is a standard physiological value that competitive exam aspirants should be familiar with.
Correct Option: B) 15–18 times/min
The question asks about the primary cause of muscle cramps after heavy exercise. This is a common physiological response to intense physical activity. We need to identify the metabolic byproduct that accumulates in muscles under anaerobic conditions, leading to pain and cramps.
Correct Option: C) Accumulation of lactic acid
UPSC - 2019
The question asks to identify the incorrect statement regarding recent developments in science, particularly in the field of biotechnology and genetic engineering. We need to evaluate each option based on current scientific capabilities.
Correct Option: A) Functional chromosomes can be created by joining segments of DNA taken from cells of different species. This statement is incorrect. While recombinant DNA technology allows joining DNA segments from different species, creating a fully functional, hybrid chromosome with all necessary structural and regulatory components by simply joining segments from different species is not currently possible.
The question asks to identify the primary organ responsible for gas exchange in the human body. This is a fundamental concept in human anatomy and physiology, specifically related to the respiratory system.
C) Lungs — The lungs are the primary organs of the respiratory system where the vital process of gas exchange (oxygen intake and carbon dioxide release) takes place in the alveoli.