SORU: aşağıdaki parçaya göre cevaplayınız
It is understood from the passage that ----.
There are several factors that increase the risk of
cancer. Mutations that affect genes are believed to
contribute to the development of cancer. These genes
produce proteins that regulate growth and alter cell
division and other basic cell properties. Cancer-causing
genetic mutations may result from the damaging effects
of drugs and viruses. Additionally, environmental factors
such as air pollution and radiation increase the risk of
cancer. Some chemicals like pesticides are known to
cause cancer, and many others are suspected of doing
so, but more study is needed to identify those chemicals
that increase the risk. The threat of cancer may also
vary according to geographical features. This
geographic variation in cancer risk is multifactorial: a
combination of genetics, diet and environment. For
example, the Japanese, who follow a diet that mainly
includes smoked foods, have high rates of colorectal
cancer. When they immigrate to the US and eat a
Western diet, the risk level declines to that of the US.
Age is another risk factor. While some cancers like
Vilms’ tumor occur almost exclusively in children,
cancers of the lungs and kidneys are more common in
older people, probably due to constant exposure to
carcinogens and weakening of the body’s immune
system. However, not all people who are exposed to
carcinogens or who have other risk factors develop
cancer.