A Microbiologist Is Reading a Sputum Culture When She Notices

question 22

Multiple Choice

A microbiologist is reading a sputum culture when she notices tiny,translucent colonies growing closely around a b-hemolytic colony on sheep blood agar (SBA) .In fact,the colonies are growing in the area where the blood has been hemolyzed.What is the probable identity of the organism that is growing closely to the b-hemolytic organism,and why are they growing in the hemolyzed area?

• A) Neisseria spp., because they need the factor X in this area
• B) Haemophilus spp., because they need the factor V in this area
• C) Acinetobacter spp., because they need the factors X and V
• D) Alcalgenes spp., because they require antibiotics be added to the media

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Definitions:

Phenotypic Plasticity

Phenotypic plasticity refers to changes in the phenotype produced by a single genotype in different environments.

Reaction Norm

Reaction norm refers to the pattern of phenotypic expression of a single genotype across a range of environments. In a sense, reaction norms depict how development maps the genotype into the phenotype as a function of the environment.

Genotype

Genotype describes the genetic makeup of an individual. Although a genotype includes all the alleles of all the genes in that individual, the term is often used to refer to the specific alleles carried by an individual for any particular gene.

Natural Selection

The process by which individuals with characteristics suited to their environment are more likely to survive and reproduce, thereby influencing the genetic makeup of populations.