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 pneumoniae, or pneumococcus, is a Gram-positive, alpha-hemolytic, facultative anaerobic member of the genus Streptococcus.A significant human pathogenic bacterium, S. pneumoniae was recognized as a major cause of pneumonia in the late 19th century, and is the subject of many humoral immunity studies.. pneumoniae is one of the most common causes of bacterial meningitis in adults and young adults, along with Neisseria meningitidis, and is the leading cause of bacterial meningitis in adults in the USA. It is also one of the top two isolates found in ear infection, otitis media.