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Course: Class 10 Biology (India) > Unit 1
Lesson 5: RespirationThe respiratory system review
Key terms
| Term | Meaning |
|---|---|
| Respiratory system | The body system responsible for gas exchange between the body and the external environment |
| Pharynx (throat) | Tube connected the nose/mouth to the esophagus |
| Larynx (voice box) | Tube forming a passage between the pharynx and trachea |
| Trachea | Tube connecting the larynx to the bronchi of the lungs |
| Bronchi | Branches of tissue stemming from the trachea |
| Bronchiole | Airway that extends from the bronchus |
| Alveoli | Structures of the lung where gas exchange occurs |
| Diaphragm | Thoracic muscle that lays beneath the lungs and aids in inhalation/exhalation |
The respiratory system
The process of physiological respiration includes two major parts: external respiration and internal respiration. External respiration, also known as breathing, involves both bringing air into the lungs (inhalation) and releasing air to the atmosphere (exhalation). During internal respiration, oxygen and carbon dioxide are exchanged between the cells and blood vessels.
Respiration begins at the nose or mouth, where oxygenated air is brought in before moving down the pharynx, larynx, and the trachea. The trachea branches into two bronchi, each leading into a lung. Each bronchus divides into smaller bronchi, and again into even smaller tubes called bronchioles. At the end of the bronchioles are air sacs called alveoli, and this is where gas exchange occurs.
An important structure of respiration is the diaphragm. When the diaphragm contracts, it flattens and the lungs expand, drawing air into the lungs. When it relaxes, air flows out, allowing the lungs to deflate.
Common mistakes and misconceptions
- Physiological respiration and cellular respiration are not the same. People sometimes use the word "respiration" to refer to the process of cellular respiration, which is a cellular process in which carbohydrates are converted into energy. The two are related processes, but they are not the same.
- We do not breathe in only oxygen or breathe out only carbon dioxide. Often the terms "oxygen" and "air" are used interchangeably. It is true that the air we breathe in has more oxygen than the air we breathe out, and the air we breathe out has more carbon dioxide than the air that we breathe in. However, oxygen is just one of the gases found in the air we breathe. (In fact, the air has more nitrogen than oxygen!)
- The respiratory system does not work alone in transporting oxygen through the body. The respiratory system works directly with the circulatory system to provide oxygen to the body. Oxygen taken in from the respiratory system moves into blood vessels that then circulate oxygen-rich blood to tissues and cells.
Want to join the conversation?
Why right bronchus is wider and shorter than the left one?(12 votes)
The right lung is larger as it does not need to make space for the heart .the left lung,needs to make space for the heart as the heart is located slightly to the left.(15 votes)
- Related, are our bodies only using the oxygen? or do they use the other gases as well?(15 votes)
They use the oxygen and other gases like nitrogen to create protein and other vitamins from the air and food we eat.(4 votes)
What's asthma and how is it caused ?(8 votes)
Asthma is when a person's airways becomes inflamed, narrows and swells, and produces an overabundant amount of mucus. Asthma happens when an irritant or allergen gets into the lungs.(9 votes)
- How dose the lungs look when you have asmath(3 votes)
Asthma is what is known as an acute obstructive disease. In other words a condition that can come on suddenly and make it difficult to exhale air. The changes you would see if you could see inside the airways during an attack which contribute to this difficulty breathing out include constriction of the smooth muscle in the airway, making it narrower, increase mucus production and swelling in the lining (odema) which all reduce the diameter of the airways. The lungs themselves can become hyper inflated (think of the alveoli as overinflated balloons) as the patient is still breathing in air (often rapidly) but is unable to expel the trapped air passed narrow airways.(14 votes)
why it is advisable to not breath through mouth(1 vote)
mouth has no hair and mucous lining like nose . therefore it is not advised to breathe through mouth. As air coming from mouth is not filtered as it is from nose(16 votes)
- what will happen if the food go down the wrong pipe(3 votes)
There is a flap-like structure present at the site of forking of the pharynx into larynx and (o)esophagus, known as the epiglottis. This flap prevents the food and water ingested from entering the larynx or trachea. When we try inhaling and swallowing at the same time, such a disturbance of food entering the wrong pipe can occur, which could result in chocking. That is even why it is highly advised not to talk while eating.(5 votes)
- how is respiration necessary(3 votes)
Respiration is necessary to live. It is one of the 8 main life processes common to most living beings. Living beings need respiration to get energy from food to convert it for daily activities- movement, growth, chemical reactions, active transport, cell metabolism, nerve impulses etc.
Respiration: the process of taking in oxygen to breakdown glucose to release the stored chemical energy it contains(6 votes)
Does Brain cells need oxygen?(3 votes)
What do brain cells do?
The create nerve impulses. What are nerve impulses?
They are (technically) energy. Where do they get this energy from?
From respiration. Where does respiration occur?
In mitochondria. What does mitchondria produce and what does it need?
It produces energy along with water and carbon-dioxide molecules. It needs OXYGEN and glucose to do so.
Fun Fact: Brain cells have lots of mitochondria!(4 votes)
What do our bodies do with the 71% nitrogen that we breathe?(4 votes)- This nitrogen helps in protein synthesis, amino acids that influence growth, hormones, brain functions and the immune system.(2 votes)
- can People die if the food go down in to the wrong pipe?(2 votes)
Yes, if food goes down a person’s trachea instead of the esophagus, that person can choke and die because of the lack of oxygen.(6 votes)
