Answer to Question 1
The textbook suggests that the development of mental operations, which are actions that are performed on objects or ideas to consistently yield a result, is a hallmark development associated with the concrete operational stage. A child's ability to understand reversibility is an indication of this development.
As a child gets to the formal operational stage, they will learn to draw conclusions from a set of facts. This is called deductive reasoning. It indicates a more sophisticated way of taking in and manipulating information and is usually seen in early adolescence.
Answer to Question 2
Although American adolescents generally enjoy very good health, one out of five
adolescents has at least one serious health problem. American teenagers may even be
less healthy than their parents were at a comparable age. The primary causes appear
to be changes in lifestyle and engaging in risky behavior. These behaviors include
excessive drinking, substance abuse, reckless driving, disorders in eating behavior, and
engaging in unprotected sex. The leading causes of death among adolescents are
accidents, suicides, and homicides. African-American males and females are
significantly more likely than their European-American counterparts to die from
homicide. Sixty percent of all adolescent deaths are due to accidents, and a majority of
these accidents involve alcohol.
Changes that occur during an action potential.
Bony processes found on the femur.
Normal development of posture and spinal curves. (A) Toddler: Protruding abdomen; lumbar lordosis. (
Ectopic pregnancies. (a) An ectopic pregnancy may occur in any of the locations shown. Interstitial
A Dorsal view of a scan of the hand phalange of a child from Denisova that yielded mtDNA that differ
Processes of the Middle and Upper Troposphere: Rossby Waves and Vorticity