A major branch of virology is virus classification. Viruses can be classified according to the host cell they infect: animal viruses, plant viruses, fungal viruses, and bacteriophages (viruses infecting bacterium, which include the most complex viruses). Another classification uses the geometrical shape of their capsid (often a helix or an icosahedron) or the virus's structure (e.g. presence or absence of a lipid envelope). Viruses range in size from about 30 nm to about 450 nm, which means that most of them cannot be seen with light microscopes. The shape and structure of viruses has been studied by electron microscopy, NMR spectroscopy, and X-ray crystallography.

The most useful and most widely used classification system distinguishes viruses according to the type of nucleic acid they use as genetic material and the viral replication method they employ to coax host cells into producing more viruses:

• DNA viruses (divided into double-stranded DNA viruses and single-stranded DNA viruses),

• RNA viruses (divided into positive-sense single-stranded RNA viruses, negative-sense single-stranded RNA viruses and the much less common double-stranded RNA viruses),

• reverse transcribing viruses (double-stranded reverse-transcribing DNA viruses and single-stranded reverse-transcribing RNA viruses including retroviruses).

1. Application Form

2. Certificate of HSK

Band 6 or above (Not needed for English taught programs)

3. Photocopy of valid passport

With name, passport number & expiration date, and photo included

4. Passport photo

A recent passport-sized photo of the applicant

5. Undergraduate school transcript

6. Bachelor's degree diploma

Graduation certificate in languages other than Chinese or English should be translated into Chinese or English and be certified by notarization.

7. Two recommendation letters

Issued by Associate Professors (or above).

• Question: What is the cost of applying through ACASC?

Answer: ACASC charges a service fee of 50$ for using its online application portal. Applying through ACASC into Chinese universities attracts a service fee of $50.

• Question: Can I apply to the university directly?

Answer: Yes. ACASC gives the applicants, the chance to directly apply to their desired universities through our online application portal. We have synchronized our system to create a simple platform that connects universities and colleges in China to international students all around the world.

• Question: How can I track my application status?

Answer: To track the application status, please log in your ACASC personal account. Whenever there’s an update, you will be informed on your application status through ACASC system within a day as soon as we receive university’s notification. You will simultaneously receive ACASC auto-email about the application status. To directly inquire about your application status, feel free to send us an email to admission@acasc.cn and our team will keep you updated.

• Question: How to deal with a pending application?

Answer: When an application is pending a decision it means that your school has received it and no admissions decision has been made yet. The admissions office may have reviewed your application package or may not have.

The main cause of a pending application is usually incomplete application documents. As a result you will be requested by the school’s admission office to re-check and modify all submitted application documents or perhaps even add extra documents and then re-submit them.

To avoid further delays, carefully read the university’s comments, modify your application form on ACASC, and re-upload the required application documents. You can contact ACASC on admission@acasc.cn for any help with regards to your pending application

• How long does it take to process my application?

Processing time varies for different applications. For example to process a degree program application requires more time than a Chinese language application. Confirmation for Chinese language application by the admission office usually takes 2 to 4 weeks. However, time for degree programs application differs. For example fall semester application processing is after March, and it takes a period of 1 to 2 months. This also depends on your qualification and the number of applicants.