Age of Menarche. Menarche marks the commencement of the reproductive phase of a woman's life. Records suggest that there was a secular decline in the average age at menarche in developed countries across the 19th and 20th Centuries until the 1950s, with an average age at menarche of 15-17 years reported in the mid-19th Century.
CHARACTERISTICS: Streptococcus pyogenes is an aerobic, gram-positive extracellular bacterium. It is made up of non-motile, non-sporing cocci that are less then 2 Âµm in length and that form chains and large colonies greater then 0.5 mm in size.HARACTERISTICS: Streptococcus pyogenes is an aerobic, gram-positive extracellular bacterium. It is made up of non-motile, non-sporing cocci that are less then 2 Âµm in length and that form chains and large colonies greater then 0.5 mm in size.
Streptococcus is a genus of coccus (spherical) gram-positive bacteria belonging to the phylum Firmicutes and the Lactobacillales (lactic acid bacteria) order.n the medical setting, the most important groups are the alpha-hemolytic streptococci S. pneumoniae and Streptococcus viridans group, and the beta-hemolytic streptococci of Lancefield groups A and B (also known as âgroup A strepâ and âgroup B strepâ).