There are many different kinds of sewage treatment plants which vary in the process by which they treat wastewater. Generally, they can be classified into the following types of system: 1  Activated sludge plant (ASP). 2  Rotating disc system. 3  Submerged aerated filter (SAF). 4  Suspended Media Filters (SMF).
In certain species of sea life, male pregnancy is common. The male incubates and births live young instead of the female. Human males are not able to do so, and medical risks of a male pregnancy are extreme. Transgender individuals can become pregnant if reproductive organs are left intact. A common phenomenon is a sympathetic pregnancy, where a man exhibits all the symptoms of pregnancy along with his expectant partner.
The average human pregnancy is 40 weeks long. However, a pregnancy is considered full term between week 37 of pregnancy and week 42 of pregnancy. Babies born during week 36 of pregnancy or earlier are considered preterm or premature. Babies born during week 43 of pregnancy or after are consider post-term or post-date.