1. Explain the evolutionary pressures (microbial pathogens) that led to the deve

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Question

1. Explain the evolutionary pressures (microbial pathogens) that led to the development of the innate and adaptive immune systems 2. Provide examples and describe some key differences between components of intrinsic immunity, innate immunity and adaptive immunity 3. Describe the fundamental properties of defensins. 4. Explain the general features of the alternate, lectin, and classical complement pathways. How are the pathways initiated, what intermediates are produced, what is the end result? 5. Predict consequences for individuals that lack specific complement components due to genetic anomalies (eg non- functional genes). 6. Describe the key properties of a substance that functions as an opsonin. Explain the benefit of opsonization Describe the complement products that function as opsonins. 7. Correctly identify complement cleavage products that function as anaphylatoxins. Describe the functions and beneficial properties of an anaphylatoxin. 8. Correctly list the 4 hallmark features of inflammation (heat, swelling. pain, redness) and describe some of the biological processes involved in causing inflammation. 9. Describe the source (liver) and the biological activities of mannose binding lectin and C-reactive protein. 10. Describe examples of inhibitors of the complement pathways. Explain why it is important to have normal levels of inhibitory complement proteins. 11. Use your understanding and knowledge of these issues to speculate and theorize about the cause, treatment, and consequences of complement-related health issues.

Explanation / Answer

1). The evolutionary force that led to the development of innate and adaptive immunity is the natural selection. The inheritance of immune system mechanisms from the mother to offspring is called "innate immunity," and the adaptive immunity develops after exposure to the pathogen. The driving force for the development of adaptive immunity is exposure to pathogens. The individuals with the functional innate and adaptive immunity can better survive against the infectious diseases, which increases the reproductive and survival fitness.

2).

The body’s ability to fight against infections and prevent the invasion of foreign substances is called, “immunity.”

The primary function of immune system is to provide protection against the pathogenic organisms. The two-types of immunity are,

Innate immunity (inherited) is a nonspecific resistance (body’s 1st line of defence) that we have from the time of birth. Innate immunity is not triggered by the specific antigens. So, it is a non-specific defence system regardless of the type of invading agent.

Adaptive immunity (acquired) provides specific immunity against particular pathogens (generates specific antibodies) and is acquired after birth.

The difference between innate (natural) and adaptive (acquired) immunity:

Innate immunity

Adaptive immunity

Present in the body from the time of birth

Acquired after birth

Provides general protection against a wide -range of pathogens

Provides specific immunity against selective pathogen

Response is immediate

Response is late

Speed of response is constant throughout the life tome

Response speed increases with successive exposure (this is due to immunological memory)

No memory cells mediated attacks are provided during immune response, attack is rapid.

Memory cells are stored for each specific pathogen, and the attack is very diverse and specific.

Prior exposure is not required to start an immediate attack

Attack occurs from second exposure onwards.

The term "intrinsic immunity" refers to the particular mechanisms that offer specific immunity against the viral infections. For example, the genetically encoded proteins.