Homeostasis. The biological definition of homeostasis is âthe tendency of an organism or cell to regulate its internal environment and maintain equilibrium, usually by a system of feedback controls, so as to stabilize health and functioningâ.ositive feedback mechanisms. A positive feedback mechanism is the exact opposite of a negative feedback mechanism. With negative feedback, the output reduces the original effect of the stimulus.
Bacteria produce disease in one of two general ways; some bacteria damage the cells and tissues of the infected organism directly by breaking down the cells for food, other bacteria release toxins (poisons) that travel throughout the body interfering with the normal activity of the host. Pathogens.
1 Some infectious bacteria give off toxins which can make some diseases more severe. 2  Bacteria are spread in many ways including: 3  Spread by aerosols (through coughing and sneezing). 4  For example, Streptococcus. 5  Spread by surface and skin contact. 6  For example, Staphylococcus aureus, including MRSA.