Question

down syndrome *
occurs only in females.
occurs in males and females equally.
is a result of an extra chromosome.
is caused by a missing chromosome.
where does the exchange of oxygen and carbon dioxide occur in the circulatory *
system
arteries
veins
capillaries
heart

Explanation:

• Down Syndrome: It is a genetic disorder caused by an extra copy of chromosome 21 (trisomy 21). It can occur in both males and females. So, the correct statement about Down Syndrome is that it is a result of an extra chromosome.
• Exchange of oxygen and carbon dioxide: Capillaries are the smallest blood vessels with thin walls. They allow for the exchange of oxygen (from blood to tissues) and carbon dioxide (from tissues to blood). Arteries carry oxygen - rich blood away from the heart, veins carry deoxygenated blood back to the heart, and the heart is a pump for the circulatory system.

Answer:

• For Down Syndrome: is a result of an extra chromosome.
• For the exchange of oxygen and carbon dioxide: Capillaries.