compromised body in low numbers), organisms that are normally nonpathogenic can cause infection. The infectious dose will vary with the organism and the health of those infected. For example, Shigella flexneri requires the ingestion of only a few hundred organisms to cause intestinal disease. Salmonella typhi requires

Molecular biologists routinely use restriction enzymes as key reagents for a variety of applications including genomic mapping, restriction fragment length polymorphism (RFLP) analysis, DNA sequencing, and a host of recombinant DNA methodologies. Few

Unit Seven Text B l. Pre-reading Task ll. Related Information Ill. Detailed Study IV. Outline& Summary V. Home Assignment

I. Pre-reading Task II. Related Information III. Detailed Study IV. Outline& Summary V. Home Assignment

I. Pre-reading Task II. Related Information III. Detailed Study IV. Outline& Summary V. Home Assignment

Text A Pre-reading task Before reading the passage, read the questions carefully and then try to find the answers as you read the passage What may the following paragraphs tell us about?

Circle the best answer according to the passage A. he wanted to make sure the telephone number he dialed was correct B the man on the other end was very rude C. he was a policeman then D. he felt there might be something

Unit Five Text A Unit One Text B I. Pre-reading Task II. Related Information III. Detailed Study IV. Outline& Summary V. Home Assignment

Unit Seven Text A Unit Seven Text A I. Pre-reading Task II. Related Information III. Outline& Summary IV. Detailed Study V. Home Assignment By Zhu Ruina

Unit Seven Text B Unit Seven Text B I. Pre-reading Task I I. Related Information I I I. Outline Summary IV. Detailed Study V. Home Assignment