Glossary of Key Terms

• Alveoli: Tiny air sacs in the lungs where gas exchange occurs.

• Arteries: Blood vessels that carry oxygenated blood away from the heart.

• Capillaries: Tiny blood vessels that connect arteries to veins, allowing for gas and nutrient exchange.

• Circulatory System: A network of organs and vessels that transport blood, nutrients, and oxygen throughout the body.

• Digestive System: A system of organs that breaks down food, absorbs nutrients, and eliminates waste.

• Excretory System: A system of organs that removes waste products from the body, including the kidneys, ureters, bladder, and urethra.

• Heart: A muscular organ that pumps blood throughout the body.

• Kidneys: Organs that filter blood and produce urine.

• Lungs: Organs that facilitate gas exchange between the blood and air.

• Veins: Blood vessels that carry deoxygenated blood back to the heart.