what is its layered defense ?
Physical barriers prevent pathogens such as bacteria and viruses from entering the organism.
Immune system
physical barriers prevent pathogens such as bacteria and viruses from entering the organism.
where is the thymus gland located in the human body The thymus is located in the upper front part of the chest, in the anterior superior mediastinum, behind the sternum, and in front of the heart. what is this gland ? The thymus is a specialized primary lymphoid organ of the immune system. can it be removed ? Yes, The thymus is a specialized primary lymphoid organ of the immune system. what is its structure ? In children, the thymus is pinkish-gray, soft, and lobulated on its surfaces. At birth it is about 4–6 cm long, 2.5–5 cm wide, and about 1 cm thick. It increases in size until puberty, where it may have a size of about 40–50 g, following which it decreases in size in a process known as involution. is it present in any other animal ? Yes, The thymus is present in all jawed vertebrates what is the system you mentioned above ? The immune system is a host defense system comprising many biological structures and processes within an organism that protects against disease.
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Immune system [SEP] Layered defense
The immune system protects its host from infection with layered defenses of increasing specificity. In simple terms, physical barriers prevent pathogens such as bacteria and viruses from entering the organism. If a pathogen breaches these barriers, the innate immune system provides an immediate, but non-specific response. Innate immune systems are found in all plants and animals. If pathogens successfully evade the innate response, vertebrates possess a second layer of protection, the adaptive immune system, which is activated by the innate response. Here, the immune system adapts its response during an infection to improve its recognition of the pathogen. This improved response is then retained after the pathogen has been eliminated, in the form of an immunological memory, and allows the adaptive immune system to mount faster and stronger attacks each time this pathogen is encountered.