topic 3: gas exchange system and respiration
Each day we breathe about 20,000 times. All of this breathing couldn't happen without help from the gas exchange system. With each breath, you take in air through your nostrils and mouth, and your lungs fill up and empty out. As air is inhaled, the mucous membranes of the nose and mouth warm and humidify the air.
Although we can't see it, the air we breathe is made up of several gases. Oxygen is the most important for keeping us alive because body cells need it for energy and growth. Without oxygen, the body's cells would die.
Carbon dioxide is the waste gas that is produced when carbon is combined with oxygen as part of the body's energy-making processes. The lungs and gas exchange system allow oxygen in the air to be taken into the body, while also enabling the body to get rid of carbon dioxide in the air breathed out.
Although we can't see it, the air we breathe is made up of several gases. Oxygen is the most important for keeping us alive because body cells need it for energy and growth. Without oxygen, the body's cells would die.
Carbon dioxide is the waste gas that is produced when carbon is combined with oxygen as part of the body's energy-making processes. The lungs and gas exchange system allow oxygen in the air to be taken into the body, while also enabling the body to get rid of carbon dioxide in the air breathed out.
Identify the organelle that produces energy
It is the many internal folds of the inner membrane that allow mitochondria to be efficient at producing ATP. And in the presence of oxygen, the organelle is highly efficient. Even though, cells that needs lots of energy may have thousands of these organelles.
The aerobic phases of cellular respiration in eukaryotes occur within organelles called mitochondria. These aerobic phases are the Krebs Cycle and the electron transport chain. Mitochondria are sometimes referred to as the "power plants" of the cell, as these are the organelles that generate most of the cell's supply of ATP.
The aerobic phases of cellular respiration in eukaryotes occur within organelles called mitochondria. These aerobic phases are the Krebs Cycle and the electron transport chain. Mitochondria are sometimes referred to as the "power plants" of the cell, as these are the organelles that generate most of the cell's supply of ATP.
Define and Explain the process of respiration releases energy in living organisms
image from bioaktivator.systime.dk
Respiration is the process of releasing energy from the breakdown of glucose. Respiration takes place in every living cell, all of the time and all cells need to respire in order to produce the energy that they require.
During the process of respiration, oxygen is ingested and chemically broken down, or oxidized, to provide energy for the living organism. This process takes place in the mitochondrion of the cell. The end process is the formation of energy and the expulsion of carbon dioxide, water vapor and heat. For humans, oxygen is inhaled through the lungs and broken down as carbon dioxide is exhaled, while with plants, the opposite occurs, and carbon dioxide is ingested and oxygen is produced instead.
There is an important distinction between plants that absorb carbon dioxide and animals that inhale it. For plants, their process is referred to as cellular respiration while respiration that solely inhales oxygen and emits carbon dioxide is simply referred to as respiration. This process happens for all kinds of living creatures. Mammals experience it in the lungs, fish experience it in the gills, earthworms experience it in their skin and amoebas experience it in their cell surface.
During the process of respiration, oxygen is ingested and chemically broken down, or oxidized, to provide energy for the living organism. This process takes place in the mitochondrion of the cell. The end process is the formation of energy and the expulsion of carbon dioxide, water vapor and heat. For humans, oxygen is inhaled through the lungs and broken down as carbon dioxide is exhaled, while with plants, the opposite occurs, and carbon dioxide is ingested and oxygen is produced instead.
There is an important distinction between plants that absorb carbon dioxide and animals that inhale it. For plants, their process is referred to as cellular respiration while respiration that solely inhales oxygen and emits carbon dioxide is simply referred to as respiration. This process happens for all kinds of living creatures. Mammals experience it in the lungs, fish experience it in the gills, earthworms experience it in their skin and amoebas experience it in their cell surface.
Explain how oxygen is required by all cells to carry out cellular respiration (more complicated knowledge of
the process is not required)
the process is not required)
Energy is needed for life processes such as:
- growth and repair
- movement
- control of body temperature in mammals
State the primary energy sources within an organism
In photosynthesis: 6CO2 + 12H2O > C6H12O6 + 6O2 + 6H2O
So the plant takes up carbon dioxide and gives out oxygen
In respiration: C6H12O6 + 6H2O > 6CO2 + 6H2O
So the plant gives out carbon dioxide
So the plant takes up carbon dioxide and gives out oxygen
In respiration: C6H12O6 + 6H2O > 6CO2 + 6H2O
So the plant gives out carbon dioxide
Compare aerobic and anaerobic respiration
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The respiration process is carried out in two ways in living organisms; Aerobic and Anaerobic.
Aerobic respiration:
This is a very complex process and involves chemical reactions during which oxygen is used in converting glucose into carbon dioxide and water. In this process energy is generated in the form of ATP, which are the carriers of energy. The start and end of aerobic respiration is usually the same if the glucose is to be broken down. Although burning is a type of aerobic process, the energy released in it is heat. But in aerobic respiration the release of energy is done in controlled way and hence very little energy is wasted in the form of heat. Most of the energy released is utilized by cells for growth and other activities.
Anaerobic respiration:
During this process glucose is broken down and energy, lactic acid or ethanols along with carbon dioxide are released as the byproduct. This process is also known as fermentation. The anaerobic respiration is carried out in humans for only a short time. When the respiration has build up enough, muscles stop the production of lactic acid. But this process is extensively carried out in micro organisms like yeast which undergoes aerobic respiration when oxygen is present and in its absence respires anaerobically and creates alcohol
Aerobic respiration:
This is a very complex process and involves chemical reactions during which oxygen is used in converting glucose into carbon dioxide and water. In this process energy is generated in the form of ATP, which are the carriers of energy. The start and end of aerobic respiration is usually the same if the glucose is to be broken down. Although burning is a type of aerobic process, the energy released in it is heat. But in aerobic respiration the release of energy is done in controlled way and hence very little energy is wasted in the form of heat. Most of the energy released is utilized by cells for growth and other activities.
Anaerobic respiration:
During this process glucose is broken down and energy, lactic acid or ethanols along with carbon dioxide are released as the byproduct. This process is also known as fermentation. The anaerobic respiration is carried out in humans for only a short time. When the respiration has build up enough, muscles stop the production of lactic acid. But this process is extensively carried out in micro organisms like yeast which undergoes aerobic respiration when oxygen is present and in its absence respires anaerobically and creates alcohol
Express aerobic respiration by a balanced equations
Express anaerobic respiration by a balanced equations
Explain the difference between breathing and respiration
Breathing is the mechanical action of getting air in and out of the lungs.
It is carried out by expanding and contracting the ribcage using the muscles located in between the ribs (these comprise the meat eaten when people have ribs from pork or whatever animal). The diaphragm is another muscle that participates in this process. It is a thin layer of muscle, separating the thoracic cavity from the abdominal cavity. When the diaphragm moves downwards it pulls air into the body as if it was the plunger of a syringe.
Respiration is the chemical reaction that provides the energy that makes the organism function. It occurs in the cells, more precisely in the mitochondria.
Organisms need energy to move, to keep warm, to perform digestion and other chemical processes.
Respiration is a chemical reaction that tranfers chemical energy contained in the glucose molecule to the ATP molecule, which is the energy "currency" of living things.
It is carried out by expanding and contracting the ribcage using the muscles located in between the ribs (these comprise the meat eaten when people have ribs from pork or whatever animal). The diaphragm is another muscle that participates in this process. It is a thin layer of muscle, separating the thoracic cavity from the abdominal cavity. When the diaphragm moves downwards it pulls air into the body as if it was the plunger of a syringe.
Respiration is the chemical reaction that provides the energy that makes the organism function. It occurs in the cells, more precisely in the mitochondria.
Organisms need energy to move, to keep warm, to perform digestion and other chemical processes.
Respiration is a chemical reaction that tranfers chemical energy contained in the glucose molecule to the ATP molecule, which is the energy "currency" of living things.
Explain the role of diffusion in gas exchange
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Diffusion is the movement of particles from an area of high density to an area of low density. In this way gasses will move from an area dense with gas to an area of low density.
In the circulatory system oxygen enters the blood and carbon dioxide leaves the blood via gaseous exchange. Gasses move across the walls of alveoli to an area of lower density than they are in: Oxygen moves into the blood as there is a low density of oxygen in the blood; Carbon dioxide moves into the lungs as it is an area of lower density. This is actually a form of excretion would you believe it, as carbon dioxide is a metabolic waste product from respiration.
In the circulatory system oxygen enters the blood and carbon dioxide leaves the blood via gaseous exchange. Gasses move across the walls of alveoli to an area of lower density than they are in: Oxygen moves into the blood as there is a low density of oxygen in the blood; Carbon dioxide moves into the lungs as it is an area of lower density. This is actually a form of excretion would you believe it, as carbon dioxide is a metabolic waste product from respiration.
image from ernursescare.blogspot.com
Explain the difference between inhaled and exhaled air
The composition of exhaled air (air that is breathed out) is very different from the composition of inhaled air (air that is breathed in). Inhaled air has the same composition as normal air, it contains:
- 78% nitrogen
- 21% oxygen
- 1% inert gas such as argon
- 0.04% carbon dioxide
- little water vapour
- 78% nitrogen
- 17% oxygen
- 1% inert gas such as argon
- 4% carbon dioxide
- saturated with water vapour
Explain how alveoli are adapted for gas exchange by diffusion between air in the lungs and blood in capillaries
image from www.getting-in.com
Lungs contain millions of microscopic air sacs called alveoli. Each alveolus is made from a single layer of thin, flat cells called alveolar epithelium. This means there’s a short diffusion pathway (which speeds up diffusion).There is a large number of alveoli in the lungs, which means there’s a big surface area for exchanging oxygen (O2) and carbon dioxide (CO2). The large number of alveoli means there’s a large surface area for gas exchange. The alveoli are surrounded by a network of capillaries which are also single layer thin.
Describe the circulatory system as a system of tubes with a pump and valves to ensure one way flow of blood
throughout the body
throughout the body
The circulatory system is the system of organs that circulates blood and lymph through the body, consisting of the heart, blood vessels, blood, lymph, and the lymphatic vessels and glands. The structure of the circulatory system is a blood vessels that transports nutrients and oxygen throughout the body.
Blood travels in a circular path through the circulatory system. The heart pumps blood to all parts of the body, and within about a minute, that blood returns to the heart to be pumped out once again. All cells of the body get their resources from the circulatory system, either directly or indirectly, depending on their proximity to blood vessels. Within the structure of the circulatory system, the heart is its center.
Blood travels in a circular path through the circulatory system. The heart pumps blood to all parts of the body, and within about a minute, that blood returns to the heart to be pumped out once again. All cells of the body get their resources from the circulatory system, either directly or indirectly, depending on their proximity to blood vessels. Within the structure of the circulatory system, the heart is its center.
Describe the structure and functions of arteries, veins and capillaries
here are three kinds of blood vessels: arteries, veins, and capillaries. Each of these plays a very specific role in the circulation process.
Arteries carry oxygenated blood away from the heart. They’re tough on the outside but they contain a smooth interior layer of epithelial cells that allows blood to flow easily. Arteries also contain a strong, muscular middle layer that helps pump blood through the body.
Capillaries connect the arteries to veins. The arteries deliver the oxygen-rich blood to the capillaries, where the actual exchange of oxygen and carbon dioxide occurs. The capillaries then deliver the waste-rich blood to the veins for transport back to the lungs and heart.
Veins carry the blood back to the heart. They’re similar to arteries but not as strong or as thick. Unlike arteries, veins contain valves that ensure blood flows in only one direction. (Arteries don’t require valves because pressure from the heart is so strong that blood is only able to flow in one direction.) Valves also help blood travel back to the heart against the force of gravity.
Arteries carry oxygenated blood away from the heart. They’re tough on the outside but they contain a smooth interior layer of epithelial cells that allows blood to flow easily. Arteries also contain a strong, muscular middle layer that helps pump blood through the body.
Capillaries connect the arteries to veins. The arteries deliver the oxygen-rich blood to the capillaries, where the actual exchange of oxygen and carbon dioxide occurs. The capillaries then deliver the waste-rich blood to the veins for transport back to the lungs and heart.
Veins carry the blood back to the heart. They’re similar to arteries but not as strong or as thick. Unlike arteries, veins contain valves that ensure blood flows in only one direction. (Arteries don’t require valves because pressure from the heart is so strong that blood is only able to flow in one direction.) Valves also help blood travel back to the heart against the force of gravity.
Describe the transfer of materials between capillaries and tissue (diffusion and osmosis)
Capillary exchange includes all exchanges that happen at the microcirculatory or capillary level. When capillaries penetrate the tissues, they branch or arborize out to maximize the surface area for the exchange of material that includes gases, nutrients, ions, and waste products. This also minimizes the distance between the capillaries and interstitial regions where such exchanges will occur. Altogether, capillaries contain about 7% of the blood in the body, and they are continuously exchanging material between the interstitial fluid.
Substances are exchanged between capillaries and interstitial fluid via three mechanisms:
The only things excluded from passing through the capillary wall are plasma proteins and whole cells. Other properties that regulate capillary exchange include:
Substances are exchanged between capillaries and interstitial fluid via three mechanisms:
- Diffusion - is the primary mechanism by which small molecules flow across capillaries and into the interstitial fluid, and vice versa, from the interstitial fluid into the capillaries
- Bulk flow - is used for the exchange of small lipid-insoluble substances. This exchange is regulated by the architecture of the capillaries with continuous capillaries that have a tight structure reducing bulk flow.
- Transcytosis or vesicular transport - is when substances in the blood move across the endothelial cell lining, but exit these cells via exocytosis.
The only things excluded from passing through the capillary wall are plasma proteins and whole cells. Other properties that regulate capillary exchange include:
- Close proximity of a capillary to an interstitial fluid region, which decreases the capillary diffusion rate distance.
- A large surface area due to capillary branching within the tissue that maximizes the surface area available for capillary exchange.
- The blood flow in the capillaries, however, is relatively slow.
Describe how our body sense that we need to breathe faster
Everyday functions of the body like digesting your food, moving your muscles or even just thinking, need oxygen. When these processes happen, a gas called carbon dioxide is produced as a waste product. The job of your lungs is to provide your body with oxygen and to get rid of the waste gas, carbon dioxide.
The regular, rhythmic contractions of the diaphragm are controlled by the brain stem. It sends nerve impulses to the diaphragm through the autonomic nervous system. The brain stem monitors the level of carbon dioxide in the blood. If the level becomes too high, it “tells” the diaphragm to contract more often. Breathing speeds up, and the excess carbon dioxide is released into the air. The opposite events occur when the level of carbon dioxide in the blood becomes too low. In this way, breathing keeps blood pH within a narrow range
When you’re active, your breathing can increase up to about 40-60 times a minute to cope with the extra demand. The delivery of oxygen to your muscles also speeds up, so they can do their job efficiently. The increase in your breathing also makes sure there’s no build-up of carbon dioxide in your bloodstream.
The regular, rhythmic contractions of the diaphragm are controlled by the brain stem. It sends nerve impulses to the diaphragm through the autonomic nervous system. The brain stem monitors the level of carbon dioxide in the blood. If the level becomes too high, it “tells” the diaphragm to contract more often. Breathing speeds up, and the excess carbon dioxide is released into the air. The opposite events occur when the level of carbon dioxide in the blood becomes too low. In this way, breathing keeps blood pH within a narrow range
When you’re active, your breathing can increase up to about 40-60 times a minute to cope with the extra demand. The delivery of oxygen to your muscles also speeds up, so they can do their job efficiently. The increase in your breathing also makes sure there’s no build-up of carbon dioxide in your bloodstream.
Describe how gas levels differ during light exercise as compared to intense exercise
Design experiments to investigate the effect of exercise on breathing in humans
Key Terms:
|
aerobic
anaerobic bronchioles alveoli veins arteries |
lactic acid
ethanol pressure differentiation capillaries exhale |
mitochondria
respiration oxygen debt exhalation carbon dioxide |
ventilation
breathing inhale diffusion |
inhalation
oxygen carbon dioxide haemoglobin |
Class Material:
Respiration in Athletics (worksheet)
Respiration of Living Organisms practical
Exhale Air practical
Control of Human Gasses practical
Anaerobic Respiration practical.
Lung worksheet
Take Your Breath Away (practical designed in class)
Effects of Smoking on the Body
Useful Links:
How The Body Responses to Exercise
Respiration from S-Cool
BBC Bitesize
Gas Exchange from Science Daily
Animation on Gas Exchange
Check out this video clip on Gas Exchange
Try Doc Brown´s quiz.
Revise respiration on Bitesize.
Revise the respiratory system on Bitesize.
Revise gas exchange on Bitesize.
Watch this excellent breathing animation
Video clips:
Respiration in Athletics (worksheet)
Respiration of Living Organisms practical
Exhale Air practical
Control of Human Gasses practical
Anaerobic Respiration practical.
Lung worksheet
Take Your Breath Away (practical designed in class)
Effects of Smoking on the Body
Useful Links:
How The Body Responses to Exercise
Respiration from S-Cool
BBC Bitesize
Gas Exchange from Science Daily
Animation on Gas Exchange
Check out this video clip on Gas Exchange
Try Doc Brown´s quiz.
Revise respiration on Bitesize.
Revise the respiratory system on Bitesize.
Revise gas exchange on Bitesize.
Watch this excellent breathing animation
Video clips:
Learn about aerobic respiration and the importance of oxygen and glucose
Respiration is the chemical process that supplies the body with energy for all other life processes: growth and repair of cells, muscle contraction, protein synthesis, sending nerve impulses, absorbing molecules in active transport to name just a few.
Ever wondered why feel all stiff the day after doing lots of exercise, in order for you to contract your muscles they need the energy that is released in respiration. However, when you're doing heavy exercise for a long time the muscles can't always get the oxygen they need to carry out aerobic respiration
Lauren explores what's actually happening when we make bread. Hint: It involves plenty of yeast, trapping carbon dioxide and linking gluten molecules.
3-D Image of the Diaphragm
Join the Amoeba Sisters for a brief tour through the human respiratory system! This video will discuss why the respiratory system is so important and address major structures such as the pharynx, larynx, trachea, bronchi, alveoli, and lungs.
When you breathe, you transport oxygen to the body’s cells to keep them working, while also clearing your system of the carbon dioxide that this work generates. How do we accomplish this crucial and complex task without even thinking about it? Emma Bryce takes us into the lungs to investigate how they help keep us alive.
Nice video clip on gas exchange
Explore the process of aerobic cellular respiration and why ATP production is so important in this updated cellular respiration video by The Amoeba Sisters!
Animals need oxygen to carry out aerobic respiration and they need to get rid of the waste product called carbon dioxide. This is called gas exchange. Swapping one gas for another.
Fish breathing
You’d think that animals that lived in water wouldn’t have to drink it -- but some fish do. Learn all about how different kinds of fish get the fresh water that they need to survive.
