Respiration

• Respiration is…

  a chemical reaction which takes place in every cell of the body to release energy
• Respiration word equation

  Glucose + oxygen > energy + carbon dioxide + water
• Released energy may be used to…

  -move muscles

  -pump chemicals in and out of cells

  -transmit impulses along nerve cells

  -make new cells

  -keep cells warm
• Air we breathe in is…

  atmospheric/inhaled air
• Air we breathe out is…

  expired/exhaled air
• Limewater(colourless to cloudy) detects…


  an increase in CO2
• Hydrogen carbonate indicator(berry red to yellow) detects…


  an increase in CO2
• Cobalt chloride paper(blue to pink) detects…


  Water molecules
• Large volume =

  small pressure
• Small volume =

  large pressure
• Inhaling

  Intercostal muscles-Contracts-pulls ribs up and out

  Diaphragm-Contracts-pulling diaphragm flat

  Thorax volume increases

  Thorax pressure decreases

  Air flow-Air sucked into lungs
• Exhaling


  Intercostal muscles-Relax-Ribs fall down and in

  Diaphragm-Relaxes-Dome shape

  Thorax volume- decreases

  Thorax pressure- increases

  Air flow- Air squeezed out of lungs
• How does breathing through your nose improve the quality of air?

  -Warmed and moistened

  -Reabsorbs water
• What happens to breathing during exercise?

  More deeply and rapidly
• What is diffusion?

  Gas exchange(through stomata/pores)
• Adaptations for gas exchange in the alveoli

  -Walls are only one cell thick

  -Large surface area

  -Moist

  -Covered by a rich network of capillaries
• The skin in the trachea and bronchi is covered in special cells:

  Ciliated epidermis
• Ciliated epidermis specialisations 


  -Some make mucus which traps germs and dust

  -Some have Cilia which waft mucus back up the throat to get swallowed and bacteria killed by stomach acid

  -If these mechanisms fail we could get colds, bronchitis, pneumonia
• Tar

  Full of carcinogens
• Carbon monoxide

  Attaches to haemoglobin faster than oxygen
• Nicotine

  Heart beats faster, raises blood pressure, thickens blood
• Smoking related diseases

  -Cancer

  -Chronic airways disease(emphysema)

  -Coronary heart disease
• Plant: cell type, respiration, photosynthesis

  -plant cells

  -respire 24/7

  -photosynthesise when light is available
• Animal: cell type, respiration, photosynthesis

  -animal cells

  -respire 24/7

  -never photosynthesise