Share
Explore BrainMass

Human Biology Questions

These are the only questions that I have left for my assignment. Any and all help would be greatly appreciated, anything added please cite your source.

EXERCISE 1 - Serodiagnosis of Infectious Disease
1. Define serum titer.
2. What are acute and convalescent sera? Why must both be tested to make a serological diagnosis of infectious disease?
3. What is the difference between an agglutination test and a precipitation test?
4. In a paired serum sample, what test results indicate recent infection?
5. What is a humoral antibody?

EXERCISE 2 - Culturing Microorganisms from the Environment
1. Why do microbiologists wear laboratory coats? Did you confirm that this is necessary?
2. Why is it necessary to wear clean, protective clothing when caring for a patient?
3. Why should hair be kept clean and out of the way when caring for patients?
4. How can the number of microorganisms in the environment be controlled?
5. When and why is hand washing important in patient care?
6. How can those who care for patients avoid spreading microorganisms among them?

EXERCISE 3 - Staphylococci
1. Differentiate the microscopic morphology of staphylococci and streptococci as seen by Gram stain.
2. What are the two types of staphylococcal coagulase?
3. What is protein A? Describe one method of detecting it.
4. What properties of S. aureus distinguish it from S. epidermidis and S. saprophyticus?
5. Why are staphylococcal infections frequent among hospital patients?

Solution Preview

EXERCISE 1 - Serodiagnosis of Infectious Disease

1. Define serum titer.

A serum titer is a serum sample containing antibody, and can be tested for the presence of detectable levels of antibody. (1)

2. What are acute and convalescent sera?

Acute sera is sera that contain the antibody level of a person who is ill. (2)
Convalescent sera is the serum of patient that has recovered from an infection after 4 weeks of treatment. (2)

Why must both be tested to make a serological diagnosis of infectious disease?

Both must be tested to make a serological diagnosis of infectious disease because the antibody of a person who is currently ill will presumably be higher confirming that the person is sick. After treatment, the convalescent sera is tested to measure the amount of antibody. The level of antibody is reduced after treatment, which we indicate that the person has recovered. Thus, the reduction of antibodies is taken to confirm the diagnosis and whether the treatment worked or not. (3)

3. What is the difference between an agglutination test and a precipitation test?
An agglutination test is the clumping of cells in the presence of an antibody; the antibody binds to multiple particles creating large complex.
It is a common method for identifying specific bacterial antigens, and the identity of bacteria. (3)

A precipitation test is based on the interaction of antibodies and antigens that come together to make one insoluble product, the precipitate. The precipitation depends on the formation of lattices ...

$2.19