Chapter 1: Overview of innate versus adaptive immunity

·        Immunity is defined as having the adequate biological defenses to disease, specifically infectious disease, or any unwanted biological invasion.
·       The collection of cells, tissues, and molecules that has the capability to resist harmful microorganisms or viruses is called the immune system, and the coordinated reaction of these cells and molecules to infectious microbes is the immune response.

Chapter 1: Overview of innate versus adaptive immunity

Immune response: Our body responds to infection by potential pathogens in different ways. These responses are known as immune responses.
Innate immune responses:
·        Innate immune responses are responses that are ‘inborn’ or ‘natural’.
·        The innate immune system provides a quick and nonspecific response to infection or foreign invasion.
·        It lacks immune memory.
·        It resists infection through several physical, chemical, and cellular approaches.
Adaptive immune responses:
·        Specific immune responses, such as the production of antibodies against a particular pathogen or its products, are known as adaptive immune responses.
·        They are developed during the lifetime of an individual as an adaptation to infection with that pathogen.
·        It is the slow response that occurs when there is a contact with the disease-causing agent.
·        Such agent can also be induced deliberately and that is called vaccination.

Lines of defense:
·        Physical and chemical barriers that tend to prevent the entry of pathogens are an organism’s first line of defense against infection. Epithelial surfaces and pH are examples of the first line of defense.
·        The second line of defense is nonspecific resistance that destroys invaders in a generalized way. Examples include phagocytes, inflammation, the complement system and fever.
·        Adaptive immunity provides the third line of defense through macrophages, T cells, and B cells. 

Table 1.1: Characteristics of Innate and Adaptive Immunity.
Innate Immunity
Adaptive Immunity
Nonspecific, first defense against pathogens.
Specific, antigen-dependent activation.
Macrophages, neutrophils, natural killer cells, and dendritic cells.
B-lymphocytes and T-lymphocytes.
Develops within minutes to hours.
Develops over period of days.
No memory.

Exercise 1.1
Which components of the immune system do the following belong to - innate or adaptive?

1. Lysozyme
2. Natural Killer cells
3. T lymphocytes
4. Epidermis
5. Fever
6. Antigen presenting cell
7. Interferon
8. Plasma cells
9. Complement
10. Toll like receptors
11. Vomiting

Post answers below!

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  1. 1 lysozymes- innate
    2 nkc- innate
    3 t lymphocytes- adaptive
    4 epidermis- innate
    5 fever- innate
    6 APC- adaptive
    7 interferon- innate
    8 plasma cells- adaptive
    9 compliment- innate
    10 tlr- adaptive
    11 vomiting- innate

  2. 1. Lysozyme - Innate
    2. Natural Killer cells - Innate
    3. T lymphocytes - Adaptive
    4. Epidermis - Innate
    5. Fever - Innate
    6. Antigen presenting cell - Adaptive
    7. Interferon - Adaptive
    8. Plasma cells - Adaptive
    9. Complement - Innate
    10. Toll like receptors - Innate
    11. Vomiting - Innate