B9: Respiration Flashcards Preview

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Flashcards in B9: Respiration Deck (16)
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Aerobic Respiration

 - what is it?

 - The equation

It is an exothermic reaction (cooler, transfers energy to the environment) where glucose is broken down reacting with oxygen to produce Carbon Dioxide and Water this releases energy from the cells which is vital for everything that goes on in your body.

  • Carbon Dioxide and Water are waste products
  • Called aerobic respiration because it uses oxygen from the air


Why do we need energy from respiration?

  • Living cells...
  • Animals...
  • Mammals and birds...
  • Plants...


  • Living cells need energy to carry out the basic functions of life
  • Animals = energy from respiration is transferred to make the muscles contract
  • Mammals and Birds = need to maintain a constant internal body temperature, ignoring the surrounding temperature
  • Plants = energy from respiration is transferred to move mineral ions, convert sugars and nitrates etc into amnio acids which build up proteins



In aerobic respiration there is a lot of chemical reactions, and these take place in the mitochondria of your cells. 

What is it?

  • Tiny rod-shaped parts (organelles) found in most plant and animal cells.
  • Folded inner membrane providing a large surface area for enzymes involved in aerobic respiration
  • Number of mitochondria in a cell shows how active the cell is



Carbohydrate store in animals


Response to exercise...


Anaerobic respiration

 - What is it

 - The equation

 - process of anerobic respiration in yeast called?

 - explain why the body uses anaerobic during vigorous exercise?

An exothermic reaction where glucose is broken down without oxygen to produce lactic acid in animals. Ethanol and Carbon Dioxide in plants and yeast. A small amount of energy is transferred for the cells (a lot less than aerobic).

  • Not as efficient as aerobic because glucose molecules aren't broken down completely.
    • Because imcomplete, it make lactic acid, not carbon dioxide and water

 - The process of anaerobic respiration in yeast is called fermentation.

 - Why the body uses anaerobic during vigorous exercise is because the body can't supply enough oxygen to the muscles and it uses anaerobic to provide energy without using oxygen which keeps the muscles going for longer.


What happens if your muscles fibres are being using vigorously for a long time?

They become fatigued and stop contracting efficiently. 


Causes of Muscle Fatigue?

Build up of lactic acid which creates an oxygen debt



Oxygen Debt 

Extra Oxygen that has to be taken into the body after exercise has stopped to finish the aerobic respiration of lactic acid.



Anaerobic respiration in other organisms...

In plant cells and some microorganisms (i.e. yeast) results in the production of ethanol and carbon dioxide.


Metabolic reactions

  - examples of this


In what organ is lactic acid converted back to glucose?




Role of the Liver

Cells grow, regenerate very rapidly. 

Metabolic functions...

  • Detoxifying poisonous substances (ethanol from alcoholic drinks)
  • Passing the breakdown products into the bood so they can be excreted in the urine via the kidneys
  • Breaking down old, worn out blood cells and storing the iron until it is needed to synthesise more blood cells

Removing Lactic Acid:

  • Remove lactic acid made by the muscles during anaerobic repiration
  • Blood flows through the muscles (transporting the lactic acid) to the liver where it converts it back to glucose.
    • Oxygen debt is repaid once lactic acid has been converted back 
    • The glucose has now been completely broken down in aerobic respiration to form carbon dioxide and water
      • if not needed, may be converted to glycogen and stored in the liver until needed


Give 2 examples of how animals use the energy transferred by respiration?

  1. Muslces contracting
  2. To keep body temperature steady
  3. To build up larger molecules from smaller ones


What is metabolism?

The sum of all of the reactions that happen in a cell or the body.


What happens to muscles when they become fatigued?

Muscles get tired and then stop contracting efficiently.