These preparations are called Vaccines. A vaccine is a biological preparation that provides active acquired immunity to a particular disease. A vaccine typically contains an agent that resembles a disease-causing micro-organism and is often made from weakened or killed forms of the microbe, its toxins or one of its surface proteins.
Answer: C. Medulla and Cortex
The nephrons are found at the cortex-medulla junction. There are what we call as the juxtamedullary nephrons and cortical nephrons referring to their designated locations. The juxtamedullary nephrons are involved in the creation of concentrated urine of a person.
Answer:
The answer is <em><u>D.
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Explanation:
Viruses can evade the processing and presentation of antigens, for example by interfering with the expression of MHC class I proteins, although this increases their susceptibility to be detected by natural killer cells (NK). However, some members of the herpesvirus, papillomavirus, retrovirus, poxvirus and flavivirus families have also developed strategies to escape the attack of NK cells and promote their survival, inhibiting cell apoptosis. Finally, some pathogens often change surface antigens frequently, as in the case of influenza viruses (orthomyxovirus).
The human immunodeficiency virus (HIV) affects CD4 + T cells and degrades the host's ability to counterattack with a strong cell-mediated immune response. There are so many tactics of immune evasion used by HIV, which have so far hindered the development of an effective vaccine.
It must be C, at the Pacific Ocean
Helium does not react with any other substances, thus the substance’s internal structure is never greatly affected and thus helium cannot have any chemical properties.
