Calf Muscles. 1  The calf muscles are six in number: the gastrocnemius, the soleus, the popliteus, the tibialis posterior, the flexor digitorum longus, and the flexor hallucis longus. 2  The gastrocnemius and the soleus run between the knee and the ankle. 3  One of the calf muscles, the soleus, has a special ability.
Air pollution leads to ozone pollution and acid rain. CFC compounds, used in aerosol sprays prior to 1995, destroy the ozone layer. Ozone pollution can cause damage to human respiratory tracts. Ozone can damage the vascular system of plants.
Secondary pollutants include: 1  Particulates created from gaseous primary pollutants and compounds in photochemical smog. Smog is a kind of air pollution. 2  Ground level ozone (O3) formed from NOx and VOCs. Ozone (O3) is a key constituent of the troposphere. 3  Peroxyacetyl nitrate (C2H3NO5) - similarly formed from NOx and VOCs.