Final answer:
People with hemophilia bleed more when cut or bruised due to a lack of clotting factors in their blood. Different versions of a gene determine whether or not a person has hemophilia.
Step-by-step explanation:
People with hemophilia bleed more when they are cut or bruised because they lack clotting factors in their blood. Clotting factors are proteins that help the blood clot, which is necessary to stop bleeding. Hemophilia is caused by different versions of a gene that determine whether or not a person has the condition.
In hemophilia A, the most common form of the disease, there is a deficiency of factor VIII, a clotting factor. Hemophilia B, the second most common form, is caused by a deficiency of factor IX.
Both of these genetic defects are linked to the X chromosome and are typically passed from a healthy female carrier to her male offspring. Females would need to inherit a defective gene from each parent to have hemophilia. Hemophilia C is a rare condition that is triggered by a nonfunctional factor XI gene on an autosomal chromosome.
In summary, different versions of a gene determine whether or not a person has hemophilia. Depending on the specific genetic defect, individuals with hemophilia have deficiencies in certain clotting factors, which causes them to bleed more when they are cut or bruised.