It is important to understand that the biological meaning of ‘Respiration’ refers to a chemical process taking place in all living cells. The function of this chemical process is to make energy available for all the cell’s activities which keep it alive. ‘ Breathing’, in some cases, plays a part but ‘respiration’ to a biologist does not mean the same as ‘breathing’.
Some of the energy released in living organisms always appears in the form of heat
Coal and wood are the carbon sources. The carbon dioxide goes up the chimney.
The word ‘respiration’ is used in everyday language to mean breathing; as in,for example, ‘respiration rate’ (breathing rate) or ‘artificial respiration’. In biology, it is best to avoid confusion by using the term ‘respiration’ for the chemical reaction in cells. ‘Artificial respiration’, is better described as ‘resuscitation’.
Organisms living in water absorb oxygen from it. But it is not the O of H 2 O that they use. The oxygen which they can use is dissolved in the water and comes, originally, from the air.
These are only a few examples. Every living process in living organisms needs energy from respiration
The drawing represents the human arm bones with two of the muscles which produce movement (biceps and triceps)
The water produced as a waste product of respiration is picked up by the blood stream and may be lost in sweat, water vapour from the lungs or in urine
The carbon dioxide bubbles plus some of the beer constituents produce a dense froth on top of the beer. The fermentation vessel is an old-fashioned open type.
All living cells are made up of chemical substancesThe processes of living involve reactions between thesubstancesFor exampleC + O2 CO2carbon oxygen carbon dioxideis an event whichproduces a changein a substance
The reaction between carbon andoxygen also releases energy in theform of heat and light (flames)Living organisms get their energy fromreactions like this (but not reactionswhich are violent enough to produceflames)
energy releasesource of carbon source ofcarbonoxygenCO2
One of the energy-producing reactions is calledrespiration(Respiration is not breathing)takes placein allall living cellsThe reaction takes place between oxygen and asubstance which contains carbon. The reactionproduces carbon dioxide and water, and releasesenergyenergy
The carbon-containing substances come fromFOOD (GLUCOSE)The oxygen comes from the AIR (or water)The energy is used to drive other chemicalreactions taking place in cellsC6H12O6 + 6O2 6CO2 + 6H2O + energysugar(glucose)oxygen carbondioxidewater
Respirationsuppliesthe energy formusclecontractiongerminationcell divisionchemical changes in cellsSome examples of the useof energy in organisms
The blood stream brings foodand oxygen to the musclecells. Respiration occurs inthe cells and releases energywhich……shoulder bladeupper armbonelower arm bonesEnergy use in muscle contraction
…….makes the muscle contractand pull the lowerarm up
(a)(b)(a) is a section cut through thelength of a maize seedling. Areasof rapid respiration are stained pink.(b) and (c) are drawings of the seedand the seedling that grows from it.Can you suggest reasons whyrespiration should be so rapid in thestained regions?embryoshootembryorootfood storeroot(c)shootroot
AnswerThe most intensely stained areas are in the root tip and theshoot tip. These are regions where very rapid cell division istaking place to produce growth. Making new cells and newcytoplasm takes a great deal of energy.You might also have noticed that, in the root, there are twofaint streaks of pink. These occur in the conducting tissue ofthe seedling. Energy is needed to transport food from thefood store to the growing region.
Glucose andoxygen react toproduce energy formuscle contraction4 RESPIRATION5 Carbon dioxideis carried to the lungsby the bloodOne example of respiration in ourselvesOne example of respiration in ourselves1. Air taken in1.Food taken in2. The lungs absorb oxygenfrom the air2.The stomach andintestine digest food.One of the productsis glucose3.The blood streamcarries glucose andoxygen to the muscles
RespirationRespirationThe glucose is notnot completely broken down to CO2 and H2Obut to CO2 and alcohol (ethanol).release of energy when foodstuffs suchas glucose react with oxygenwith oxygen to producecarbon dioxide and water.aerobic respiration.which does not need oxygendoes not need oxygenand is called anaerobicrespiration
C6H12O6 2C2H5OH + 2CO2glucose alcoholenergyFor example, our own muscles resort to anaerobicrespiration when oxygen is not delivered to them fastenough.* LESS energy released* Anaerobic respiration takes place at some stage in the cellsof most living organisms.anaerobic respiration
sugar is broken down to alcohol and carbon dioxide* pizza-making* pizza-making* brewing* brewing* wine-making* wine-makingfermentation.One form of anaerobic respiration in bacteria and yeastsis called
AEROBICRESPIRATIONSIMILARITIES ANAEROBICRESPIRATION*USES O2 *E released by breakdownof SUGAR*Don’t use O2* always producesCarbon dioxide+water*ATP made *CO2 sometimesmade*Large amount of EEreleased*Some energy lost as HEATHEAT *Small amount of eereleased*ALCOHOL orLACTID ACID made