Thank you for reporting, we will resolve it shortly
Q.
The type of immunity that is present at the time of birth in humans is:
NTA AbhyasNTA Abhyas 2020Human Health and Disease
Solution:
The innate immune system, also known as non-specific immune system, is the first line of defence. It comprises the cells and mechanisms that defend the host from infection by other organisms in a non-specific manner. This means that the cells of the innate system recognize and respond to pathogens in a generic way. Innate Immunity is present at the time of birth. Innate immunity consists of four types of barriers.
$\cdot $ Physical barriers: Skin on our body is the main barrier which prevents entry of the micro-organisms. Mucus coating of the epithelium lining the respiratory, gastrointestinal and urogenital tracts also help in trapping microbes entering our body.
$\cdot $ Physiological barriers: Acid in stomach, saliva in the mouth, tears from eyes all prevent microbial growth.
$\cdot $ Cellular barriers: Certain types of leukocytes (WBC) of our body such as polymorph nuclear leukocytes (PMNL-neutrophils) and monocytes and natural killer cells in the blood as well as macrophages in tissues can phagocytise and destroy microbes.
$\cdot $ Cytokine barriers: Virus-infected cells secrete proteins called interferon which protect non-infected cells from further viral infection.