Hemophilia a Is an X-Linked Recessive Genetic Condition

question 75

Multiple Choice

Hemophilia A is an X-linked recessive genetic condition.In humans it is due to a mutation in the F8 gene,which encodes a protein called coagulation factor VII.Coagulation factors are proteins important in blood clotting.Individuals with hemophilia,when injured,bleed longer than a normal,healthy individual;the inability to normally clot blood can be life threatening.Which of the following statements is NOT a reason why hemophilia is much more common in males than in females?

• A)A female with one defective allele makes enough normal coagulation factor VII to clot blood and will not have hemophilia A
• B)Males are hemizygous for the F8 gene,so they will have hemophilia A if they have one defective allele
• C)Females have to receive a defective allele from both their mother and their father to get hemophilia A
• D)Males have to receive a defective allele only from their father to get hemophilia A

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Definitions:

Variable Costs

Expenses that vary directly with the level of production or sales volume, such as materials and labor.

Fixed Costs

Costs that do not change with the level of production or sales, such as rent, salaries, and insurance.

Unit Contribution Margin

The difference between the selling price per unit and the variable cost per unit, indicating how much each unit sold contributes to fixed costs and profit.

Variable Costs

Expenses that fluctuate directly with the volume of production or sales, such as raw materials and direct labor costs.