062 Pressure Changes during Breathing

This video tutorial by Leslie Samuel explores the mechanics of breathing, focusing on pressure changes during inhalation and exhalation. It covers the anatomy of the thoracic, pleural, and pulmonary cavities, and the roles of the diaphragm and intercostal muscles. The tutorial explains how these muscles contract and relax to facilitate breathing, and discusses the differences between normal and forced breathing. The video concludes with a summary and directs viewers to additional resources on interactive-biology.com.

What is the primary function of the alveoli in the lungs?

• To humidify the air

• To exchange oxygen and carbon dioxide with the blood

• To filter out dust particles

• To produce mucus

Which cavity is located inside the lungs?

• Thoracic cavity

• Pleural cavity

• Pulmonary cavity

• Abdominal cavity

What happens to the diaphragm during inhalation?

• It remains stationary

• It contracts and moves down

• It relaxes and moves up

• It contracts and moves up

How do the external intercostal muscles contribute to inhalation?

• They contract and lower the rib cage

• They relax and lower the rib cage

• They relax and raise the rib cage

• They contract and raise the rib cage

During exhalation, what causes the air to be expelled from the lungs?

• Increase in pressure inside the lungs

• Increase in pressure outside the lungs

• Decrease in pressure inside the lungs

• Decrease in pressure outside the lungs

What additional muscles are involved in forced exhalation?

• External intercostals

• Diaphragm

• Neck muscles

• Internal intercostals

What is the main difference between normal and forced breathing?

• Normal breathing decreases pressure more

• Forced breathing involves stronger muscle contractions

• Normal breathing uses more muscles

• Forced breathing uses less energy