NCERT Biology class 12 online notes - Pathogen
Takshila Learning offers animated videos, NCERT solutions, question bank and sample papers for school courses and designed according to latest pattern of CBSE question papers. Further, Takshila learning also provides online classes for CS Course, Banking exam preparation, and Digital Marketing. We regularly provide different blogs and articles on important articles, news, and information related to CBSE exams.
Biology class 12 : We define a pathogen as a biological agent that causes disease or illness to its host (an organism which is attacked by the pathogen).
Most often the pathogens disrupt the normal physiology of a multi-cellular animal or plant. However, pathogens can infect unicellular organisms from all of the biological kingdoms. There are several substrates and pathways whereby pathogens can invade a host. The human body contains many natural defenses against some of the common pathogens in the form of the human immune system and by some “helpful” bacteria present in the human body’s normal flora. Some pathogens have been found to be responsible for massive amounts of casualties and have had numerous effects on afflicted groups. Today, while many medical advances have been made to safeguard against infection by pathogens, through the use of vaccination, antibiotics, and fungicide, pathogens continue to threaten human life. Social advances such as food safety, hygiene, and water treatment have reduced the threat from some pathogens.
Pathogens have evolved specific mechanisms for interacting with their hosts
The human body is a complex and thriving ecosystem. It contains about 1013 human cells and also about 1014 bacterial, fungal, and protozoan cells, which represent thousands of microbial species. These microbes, called the normal flora, are usually are found in certain areas of the body, including the skin, mouth, large intestine, and vagina. In addition, humans are always infected with viruses, most of which rarely, if ever, become symptomatic. If it is normal for us to live in such close intimacy with a wide variety of microbes, how is it that some of them are capable of causing us illness or death?
Pathogens are usually distinct from the normal flora. Our normal microbial inhabitants only cause trouble if our immune systems are weakened. The pathogens have developed highly specialized mechanisms for crossing cellular and biochemical barriers and for eliciting specific responses from the host organism that contribute to the survival and multiplication of the pathogen.
In order to survive and multiply in a host, a successful pathogen must be able to:
(1) Colonize the host
(2) Find a nutritionally compatible niche in the host body.
Read more... Biology class 12 online Notes - Pathogen
For Class 12th online classes, NCERT solutions, CBSE guide, sample papers, latest updates from CBSE Board, enroll in Takshila Learning.
Comments
Post a Comment
Thank you we will contact ASAP.