In immunology, colonal selection theory explains the functions of cells in response to specific antigens invading the body. According to this theory, a specific antigen molecule activates the immune system by identifying and binding to a specific receptor located on the membrane of a circulating lymphocyte. This bonding stimulates the lymphocyte to divide numerous times and produces a large number of clones of cells. Prior to exposure to antigens, such clones takes weeks or months to occur. Subsequent exposure causes B cell clones to develop into plasma cells and secrete antibodies. These antibodies rapidly destroy the invading antigens.
describe the colonal selection theory and explain how it accounts for the ability to defend against...
Evolution by natural selection, initially described by Charles Darwin, is the theory that explains how a population’s inherited traits change over time and describe why organisms must adapt to their environments. Evolutionary theory can explain how specialized features develop in different species.
1. Describe how the process of natural selection works, and how it results in adaptations (Darwin's Observations and Conclusions) • How does unequal reproductive success lead to natural selection? What are adaptations? Explain Darwin’s observations and conclusions. • Describe evolution by natural selection? What are some important points about evolution? 2. Describe examples of and evidence for evolution by natural selection that can be seen in your daily life. 3. Discuss the different kinds of evidence that support the theory...
Briefly describe Charles Darwin’s theory of evolution by natural selection.
A. Please explain an example of a system that is an institution, and defend that characterization through reference to at least 4 attributes of an institution. B. Which theory of institutional change best fits the institution you described earlier? Why is that theory more appropriate than the others to describe changes to that institution over time?
1. Identify and define the main tenets of Marxist theory. 2. Describe how Marxist theory enables users to challenge the status quo. 3. Explain the potential Marxist theory has as tool in the Social Sciences, and in your field, in particular.
How can a mortuary defend themselves from a case of negligence against them?
what are cyber security threats and how do you defend against them ?
1. What natural defenses are present in gastrointestinal tract? 2. How does mucus defend against microbial attack? 3. How do dental caries develop? 4. What is periodontitis and describe the features of each stage? 5. How is STEC different from other E. coli? How did it acquire this ability? 6. How does a person acquire STEC? 7, How are STEC infections treated? 8. How do natural disasters contribute to the transmission of cholera? 9. What does cholera toxin do to...
Describe Darwin's theory of Natural Selection as a means of Transmutation of Species. Focus especially on how the struggle for life produces new species. The theory as Darwin knew it was incomplete, allowing 19th century biologists and psychologists to believe in varying theories of evolution. What do we now know about in biology that Darwin did not that makes the current “NeoDarwinist” paradigm complete?
help！！ Immune system is our body defense system against foreign pathogens. Describe how innate and adaptive immunity respond and defend against a novel virus, such as SARS-CoV-2