Why is a person who has klinefelter's syndrome (xxy) a male, even though he has two x chromosomes in his cells?

Which of the following describes a difference when gram-positive bacteria are compared to gram-negative bacteria?

The carbon cycle is best defined as a process in which a. carbon changes from inorganic forms to organic forms and back b. carbon is changed into other elements such as oxygen or nitrogen c. carbon is continually created from the sun’s energy by plants d. carbon is consumed and regenerated from other elements such as oxygen and nitrogen

What are the student's observations and inferences before he starts his investigation?