HTHSCI 2HH3 Lecture Notes - Lecture 3: Cyclic Adenosine Monophosphate, Enzyme, Botulism

• School: McMaster University
• Department: Health Sciences
• Course: HTHSCI 2HH3
• Professor: Kirsten Culver

Document Summary

Many benefit the host, or simply colonize the host without causing disease. Human body: 10 trillion cells + 100 trillion bacterial cells: bacteria far exceed the number of somatic cells that make up the body. Host factors greatly influence the relationship between microbe and host. Mice born without any bacteria performed very poorly: with each successive addition of bacteria, they began to perform significantly better. Saprophytic mycobacteria of the ear and external genitals: live on secretions and sloughed-off cells causing no benefit or harm to the host. Escherichia coli in the large intestine synthesize vitamin k: vitamin k is absorbed into the blood stream and is used by the host. In return, the large intestine of the host provides nutrients used by the bacteria, facilitating their survival. This is the relationship we are concerned about in this course. This is an infectious process not colonization. One organism benefits from the relationship at the expense of the other.