Breathing and Respiration in Humans

• When you breathe in, your ribs move up and out.
• The diaphragm is the muscle that moves up and down to help with breathing.
• When breathing in, the gas you take in is oxygen.
• When you breathe out, the gas released is carbon dioxide.
• The diaphragm moves up when you exhale.
• The main purpose of respiration is to release energy.
• The word equation for aerobic respiration: Glucose + Oxygen → Carbon dioxide + Water + Energy.
• Respiration happens in the mitochondria of the cell.
• Cells use glucose for energy during respiration.
• Breathing is a physical process, while respiration is a chemical process that happens in cells.
• The main function of the lungs is to absorb oxygen and remove carbon dioxide.
• The volume of the chest increases when you inhale.
• Ciliated cells in the airways filter and remove mucus and dust.
• The trachea connects the mouth and nose to the lungs.
• The ribs protect the lungs and help them expand.
• Respiration involves the release of energy from food.
• Carbon dioxide is a waste product of respiration.
• Mitochondria's role in respiration is to release energy from glucose.
• Aerobic respiration is the type that requires oxygen.
• Respiration is needed to release energy for body functions.
• The trachea carries air from the throat to the lungs.
• When you inhale, the diaphragm moves down.
• Breathing allows the intake of oxygen and removal of carbon dioxide.
• Lungs expand when air enters.
• The epiglottis prevents food from entering the trachea when swallowing.
• Alveoli are responsible for gas exchange in the lungs.
• A key function of respiration is to release energy from food.
• The respiratory system is responsible for respiration.
• Aerobic respiration produces carbon dioxide, water, and energy.
• Oxygen is needed for aerobic respiration.
• Red blood cells transport oxygen during respiration.
• Respiration occurs in the mitochondria in a cell.

Medium Difficulty

• During inhalation, chest cavity volume increases.
• Intercostal muscles help expand and contract the ribcage for breathing.
• Alveoli have thin walls to allow gases to diffuse quickly.
• Cartilage rings prevent the trachea from collapsing.
• Exhaled air contains more carbon dioxide and less oxygen than inhaled air.
• Mucus and cilia trap dust and microbes in the respiratory system.
• Respiration releases energy from glucose in cells.
• Glucose is broken down to release energy during aerobic respiration.
• Aerobic respiration uses oxygen, unlike anaerobic respiration.
• Muscles produce lactic acid during anaerobic respiration due to a lack of oxygen.
• Mitochondria releases energy from glucose.
• Energy released in respiration is used for movement, heat, and growth.

Hard Difficulty

• During inhalation, the volume of the chest cavity increasing lowers air pressure.
• Alveoli have a large surface area to increase the rate of gas exchange.
• Cilia and mucus remove dust and microbes in the airways.
• During exhalation, the ribcage moves down and in.
• Intercostal muscles help expand and contract the ribcage to assist airflow.
• A decrease in the number of capillaries surrounding the alveoli, would make gas exchange in the lungs less efficient.
• Respiration is important because it provides energy for essential processes.
• Aerobic respiration releases energy by breaking down glucose using oxygen.
• Muscle cells need more energy for movement, requiring more mitochondria than skin cells.
• The main disadvantage of anaerobic respiration in humans is lower energy production and lactic acid buildup.
• Glucose is broken down to release energy during respiration.
• A high energy demand, such as during exercise, increases the rate of respiration in cells.

Harder Difficulty

• Oxygen diffuses into the blood in the lungs because the blood has a lower oxygen concentration than the alveoli, creating a concentration gradient.
• Smoking damages the respiratory system by destroying cilia, leading to a buildup of mucus and reduced airflow.
• Surfactant in the alveoli reduces surface tension to prevent alveoli from collapsing.
• People living at high altitudes have a higher red blood cell count due to lower oxygen levels stimulating the body to produce more red blood cells to carry oxygen efficiently.
• Increased carbon dioxide levels in the blood increase breathing rate by stimulating the respiratory center in the brain.
• Hyperventilation before swimming underwater increases the risk of drowning because it tricks the brain into thinking there is less carbon dioxide, delaying the urge to breathe and increasing the risk of blackout.
• Anaerobic respiration is less efficient due to producing less ATP per glucose molecule and lactic acid accumulation.
• Energy is stored temporarily as ATP molecules in the mitochondria before usage by cells.
• Oxygen acts as the final electron acceptor in the electron transport chain during aerobic respiration.
• Lactic acid produced during anaerobic respiration in muscles is broken down in the liver using oxygen in a process called the oxygen debt.
• Cyanide poisoning inhibits enzymes in the electron transport chain, stopping ATP production, thus negatively affecting cellular respiration.
• Respiration is linked to the circulatory system because blood transports oxygen and glucose to cells and removes carbon dioxide.

Extra Hard Difficulty

• Deep-sea divers use a special gas mixture to prevent nitrogen from dissolving into the blood at high pressure, reducing the risk of decompression sickness.
• Chemoreceptors detect pH changes in the blood and stimulate the respiratory center in the brain to detect an increase in carbon dioxide levels.
• Premature babies struggle to breathe properly because their lungs have not produced enough surfactant, which causes alveoli to collapse.
• During intense exercise, the body switches to anaerobic respiration to compensate for a temporary lack of oxygen, producing lactic acid for short-term energy.
• Cyanide poisoning causes rapid death at the cellular level because it blocks the final step of the electron transport chain, preventing ATP production.
• When ATP levels drop too low, cells switch to anaerobic respiration to temporarily produce more energy.
• Many small alveoli provide a larger surface area for gas exchange, making it better for the lungs.
• If the diaphragm failed to contract properly, the volume of the chest cavity would not increase properly, reducing inhalation efficiency.

Impossible Difficulty

• If alveoli were coated with a thick layer of fluid, oxygen is unable to dissolve in the fluid, preventing diffusion into the blood, which is, in turn, the 1st and MOST IMMEDIATE impact on gas exchange.
• If lactic acid could NOT be removed from muscles cells after prolonged activity, the pH of the muscle tissue could drop, leading to enzyme denaturation and muscle failure.

Discover how your body breathes and respires. Learn about the roles of the diaphragm, lungs, and cellular respiration. Understand the difference between breathing and respiration, and the importance of oxygen and carbon dioxide exchange.