Respiratory system Flashcards
Explain the structure of the respiratory system
-nose, pharynx, larynx
-trachea
-bronchi
-bronchioles
-alveoli/lungs
Functions of the nasal cavity and mouth?
Air enters and leaves the body
-cavity is convoluted and lined w/mucous membrane
-air is filtered in
-warmed and humidified
-nose lets out secretion of mucous
-contain anti-bacterial enzymes that trap debris before lung entrance
Function of the pharynx
Also known as the throat
-the region from the nasal cavity to the top of the trachea and oesophagus
Function of larynx
Vocal chords
-constructed from 9 cartilages
-mucous membranes and air vibrations
-it’s entrance is protected by the epiglottis
Function of the trachea
-made up of c shaped cartilage rings which hold it together and prevent collapsing of tubes during inhalation
-lining of trachea secretes mucous to trap dust and debris (pathogens)
Sections of bronchi and their function
Has cilia and mucus working together to rid the lungs of dust and dirt
Starting from trachea:
-primary bronchi
-secondary bronchi
-tertiary bronchi
What is pleura?
Membrane covering the surface of the lungs (protection and cushioning)
-contains pleural fluid
Function of the alveoli
Location of gas exchange
-air sacs internally covered with oxygen dissolving fluid
-makes lungs moist
-allows for efficient gas diffusion
-has large SA
-1 cell layering surrounded by blood vessels
Define what occurs in inspiration/inhalation
Breathing in
-air moves form high to low pressure
-pressure inside lungs must be less than atmosphere
-lung volume increases while diaphragm and intercoastals contract
-ribcage becomes flatter and moves up and out while pleura adheres to the wall
Define expiration/exhalation
Air leaving the lungs
-pressure from high to low
-pressure in the atmosphere must be lower than in lungs
-lung volume will decrease as intercoastals and diaphragm relax
-diaphragm concaves and rib moves down and in
-pleura adheres to the chest wall
Why are lungs well suited to gas exchange
-Large internal SA-alveoli
-large amounts of gas are exchanged
-blood vessels well supplied
-membrane is thin so gas won’t travel far
How is concentration gradient for oxygen and carbon dioxide maintained?
-constants blood flow through the capillaries
-movement of air though the alveoli
Define anabolism and catabolism
Anabolism:
Process using energy to build/create larger or complex molecules
e.g. protein synthesis
Catabolism:
Breaking down of large molecules into smaller ones
e.g. digestion
-breaking down molecules releases energy
What is cellular respiration?
Process that releases energy by breaking down glucose and other molecules, taken in as food, in the presence of oxygen.
What is the equation for respiration?
C6H12O6 + 6O2 —–> 6CO2 + 6H2O + energy
What occurs during the change from ATP to ADP?
-phosphate molecule is stripped
-60-80% energy is released as heat
-remaining is used for biological processes
What are biological uses of ATP?
-muscle contraction
-active transport of substrates through a membrane
-growth and repair
-cell division
-transmission of nerve impulses
What is anaerobic respiration?
The release of energy from breaking down glucose which can convert 2 molecules of ADP to ATP
-without the presence of oxygen
What is glycolysis?
An anaerobic and catabolic process responsible for the breaking down of glucose into 2 pyruvate molecules.
-energy from this reaction then makes 2 ATP molecules
-occurs in the cytoplasm
Link between anaerobic respiration and vigorous activity.
Pyruvate molecules from glycolysis convert into lactic acid through fermentation due to lack of oxygen
-During vigorous activity, anaerobic respiration is used as extra energy causing lactic acid to collect in muscles, causing pain
-can be fixed when blood takes acid to the liver where it is converted into glucose
-called oxygen recovery
What is aerobic respiration?
The complete breakdown of glucose into carbon dioxide and water
-requiring the presence of oxygen
-occurs in the mitochondria
How does aerobic respiration occur
Citric acid cycle (occurs in inner membrane of mitochondria)
-Pyruvate from glycolysis converts to acetyl coenzyme A
-CoA enters the citric acid cycle (krebs cycle)
-Carbon atoms are released in carbon dioxide
-For every CoA that enters cycle, 1 molecule of ATP is produced
Therefore, 2 ATP molecules are produced from one glucose
Electron transport system (occurs in outer membrane of mitochondria)
-electrons pass between molecules
-resulting in oxygen molecules which form water
-about 26-34 ATP are produced in this process
How does gas exchange occur?
-artery to lungs brings deoxygenated blood to capillaries surrounding alveoli
- C02 diffuses from high conc in blood in capillaries to low conc in the air in the alveoli
-oxygen diffuses from higher conc in air in the alveolus to lower conc in blood
-the one cell thick wall of capillary and alveolus allows for the diffusion, through the film of moisture lining the alveolus
-now oxygenated blood leaves the capillaries of the alveoli and is taken to heart in the veins from the lungs
