1. discussion of marx, how does marx defines class and what problem does he have.

Question

2. discussion between social class and health inequalities.

Answer 1

I refer you to
http://en.wikipedia.org/wiki/Social_class
which contains the sentence:
"Karl Marx defined class in terms of the extent to which an individual or social group has control over the means of production."

As to your second question, there is a risk that the poorer members of society, or poor social classes, receive less that adequate health care. Government programs such as Medicaid and Medicare, and health insurance provided by SOME employers help alleviate this problem in the USA. Most countries have some form of universal health coverage.

Answer 2

Beside some genetic differences, the less-educated persons, usually lower class, are less aware of methods of maintaining good health, are more likely to be present-oriented ("live for today") than future-oriented (plan ahead), and tend to be more suspicious of society's institutions (including health institutions).

See http://www.members.cox.net/dagershaw/lol/PastPresentFuture.html

I hope this helps a little more. Thanks for asking.