Which five statements about hemoglobin and myoglobin structure are true? Each hemoglobin molecule can bind four oxygen molecules
, and each myoglobin can bind only one oxygen molecule. Molecular oxygen binds irreversibly to Fe2+ in heme. By itself, heme is not a good oxygen carrier. It must be part of a larger protein to prevent a change in the oxidation state of the iron ion. Both hemoglobin and myoglobin contain a prosthetic group called heme, which contains a central iron ion. Heme is composed of an organic protoporphyrin component and a metal ion. Each iron ion can form six coordination bonds: One of these bonds is formed between iron and oxygen. Hemoglobin and myoglobin are heterotetramers.
Pathogenicity is the ability to produce disease in a host organism
Microbes express their pathogenicity by means of their virulence, a term which refers to the degree of pathogenicity of the microbe
The relationship between a host and a pathogen is dynamic, since each modifies the activities and functions of the other
The outcome of such a relationship depends on the virulence of the pathogen and the relative degree of resistance or susceptibility of the host, due mainly to the effectiveness of the host defense mechanisms
Hence, general requirements for any organism to cause disease within a host are: evasion of host defenses
, gaining access to the host via a portal of entry, adherence to host tissues
As a rule of thumb, in order to improve the reliability and accuracy of an experiment, it is best if the experiment is repeated several times. The increased number of trials ensures that the readings observed have minimal random error.