1. Memory cells that trigger a secondary immune response
2. Specific antibodies that remain concentrated in the bloodstream for life after the first infection event
3. Memory cells that trigger a primary immune response
4. T cells that trigger a primary immune response
Answer:
1. Memory cells that trigger a secondary immune response
Explanation:
During the first infection when the body is invaded by a particular antigen, the immune system tries to identify the type of antigen. B lymphocytes make antibodies when the antigen has been identified in the event of a primary infection. The response of the immune system during the primary infection of that pathogen is usually slow. As soon as the primary infection is arrested by the antibodies produced in response, memory cells such as the memory B cells is formed, which enables the immune system to identify the same pathogen, and thereby triggers a faster secondary immune response in subsequent infections by the same pathogen.
If you don't understand how to upload a file for your question you just look for the button that says attach file, and the letter B is for if you want to put an answer in bold.
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I found some articles on the internet that may be helpful (took me three minutes of searching). Hope these help?
http://www.huffingtonpost.com/ravishly/neuroscience-proves-what-_b_6494820.html
http://sitn.hms.harvard.edu/flash/2016/gender-lines-science-transgender-identity/
Answer:
Red blood cells, also called erythrocytes, are the most abundant cell type in the blood.
The primary function of red blood cells is to transport oxygen to body cells and deliver carbon dioxide to the lungs.
Rhenium is the very dangerous (hazard wise) it should be handled carefully and you should understand that THIS should not be taken lightly I hope this helps!:)
