What Is the Basic Hemoglobin Defect in the Thalassemias

question 19

Multiple Choice

What is the basic hemoglobin defect in the thalassemias?

• A)One of the globin chains has an amino acid substitution.
• B)A structurally normal globin chain is absent or produced at lower levels.
• C)Heme is produced at a lower concentration.
• D)Iron is not incorporated into the protoporphyrin ring to form heme.

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Definitions:

Ecology

A discipline of biology that studies the interrelations among living things and their environments.

Zero Population Growth

Point at which the birth rate equals the death rate. A population with zero population growth does not change in size.

Increase

A rise or growth in quantity, size, intensity, or some other measure.

Population Density

The number of individuals of a species per unit of area or volume at a given time.