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.
1. Staphylococcus aureus-Staphylococcus aureus is a Gram-positive coccus (rounded shape) that is anaerobic. Staphylococcus aureus is also known as the golden cluster seed, golden staph and the seed gold. Staphylococcus bacteria are present in the nasal passages of humans and can be found on the skin and hair.. Listeria monocytogenes-Listeria monocytogenes is a Gram-positive rod-shaped bacterium. It is anaerobic. The most common infection that these bacteria cause is Listeriosis. Symptoms of this infection are headaches, nausea and vomiting; however, if the infection spreads to the nervous system, it can cause meningitis.