Practice Questions

1.Explain why two parents without cystic fibrosis can have a child with the disorder.

Cystic fibrosis (CF) is caused by a recessive gene, which means a person needs two faulty copies to have the disease.

If both parents have one dominant and one recessive allele, they will not have the disorder themselves, but they can pass on the harmful recessive allele. 

If the offspring receives one recessive allele from each parent, then they will have the condition.

2.Give two advantages of embryo screening.

Helps to prevents serious genetic diseases

It can reduce suffering

Allows parents to make an informed decision about whether to continue or terminate the pregnancy.

3.Describe how gene therapy can be used to treat inherited disorders.

Identify the faulty gene that causes the disorder.

Insert a working copy of that gene into the patient’s cells. This is usually done using a harmless virus as a “delivery vehicle.”

The new gene produces the correct protein, which helps the cells work properly.

Over time, this can reduce or even remove the symptoms of the inherited disorder