Answer:
Life expectancy is affected by both genes and environment because; 1) one could have genetic underlying health issues that could cause an untimely demise, and 2) the environment in which they live could have uncontrollable events which may shorten one's life, such as violence, limited access to health care, and pollution.
Humans possess 24 ribs, which come in pairs that are located on each side of the body. These bony structures are flattened, elongated and slightly bent around the cavity. The ribs are generally classified into three: true ribs, false ribs and floating ribs. The true ribs are directly connected to the sternum while the false ribs, or ribs eight to 10, are indirectly attached. The floating ribs, or ribs 11 to 12, are joined to the vertebrae.
