breath
Definition
Breath is the process of inhaling and exhaling air. It is essential for life because it provides our cells with oxygen. Oxygen is needed for cellular respiration, which is the process by which cells convert food into energy.
The process of breathing can be divided into two phases: inspiration and expiration. Inspiration is the process of inhaling air into the lungs. Expiration is the process of exhaling air from the lungs.
The respiratory system is responsible for breathing. The respiratory system consists of the lungs, the airways, and the muscles that help us breathe.
How can the word be used?
The wind blew gently, and I could feel the breath of the ocean on my face.
Different forms of the word
Noun:
breath (the act of breathing).
breath (the air that is breathed in and out).
breath (a light current of air).
Adjective:
breathless (unable to breathe easily).
Verb:
to breathe (to take in and expel air).
to breathe (to give life or spirit to).
Etymology
The word "breath" has an interesting etymology. It comes from the Old English word bræth, which means "breathing." The Old English word bræth is thought to be related to the Proto-Germanic word brēthan, which also means "breathing.".
Question
Why does humans need breath?
AQA Science Exam Question and Answer
Question:
Define the term "breath" in the context of respiration. Describe the process of breathing in humans and its significance in obtaining oxygen for the body.
Answer:
In the context of respiration, "breath" refers to the act of inhaling and exhaling air, which is essential for the exchange of gases in the lungs.
Process of Breathing in Humans:
Breathing in humans involves two phases: inhalation and exhalation. During inhalation, the diaphragm contracts, and the ribcage expands, causing the chest cavity to increase in volume. This expansion lowers the air pressure in the lungs, allowing air to rush in through the nose or mouth and fill the air sacs called alveoli. In contrast, during exhalation, the diaphragm relaxes, and the ribcage returns to its original position, decreasing the volume of the chest cavity. This compression increases air pressure in the lungs, forcing the air containing carbon dioxide to be expelled from the body.
Significance of Breathing for Oxygen Obtaining:
Breathing is vital in obtaining oxygen for the body. When we inhale, oxygen-rich air enters the lungs and diffuses into the bloodstream, where it binds to red blood cells and is transported to various tissues and cells throughout the body. Oxygen is crucial for cellular respiration, the process by which cells produce energy (ATP) from glucose, to fuel essential bodily functions. During exhalation, carbon dioxide, a waste product of cellular respiration, is expelled from the body, maintaining the balance of gases in the bloodstream and preventing carbon dioxide buildup, which could be harmful to the body.