Gas exchange

Alveoli

Tiny air sacs in the lungs where gas exchange occurs, characterized by thin walls and a large surface area.

Gas Exchange Surface Features

Includes large surface area, thin surface walls, and good blood and air supply to facilitate efficient gas exchange.

Inspired Air Composition

The composition of air entering the lungs, approximately 21% oxygen, 0.04% carbon dioxide, and 78% nitrogen.

Expired Air Composition

The composition of air exhaled from the lungs, approximately 16% oxygen, 4% carbon dioxide, and unchanged nitrogen content.

Role of Ribs in Breathing

Protect the lungs and assist in the mechanical process of inhalation and exhalation.

Intercostal Muscles

Muscles located between the ribs that help in expanding and contracting the thoracic cavity during breathing.

Diaphragm

A dome-shaped muscle at the bottom of the thorax essential for inhalation and exhalation.

Function of Goblet Cells

Cells that produce mucus to trap foreign particles and pathogens, aiding in lung protection.

Ciliated Cells

Cells with hair-like structures that move mucus toward the throat to be swallowed or expelled, helping to keep the airway clean.

Effect of Exercise on Breathing

Increased breathing rate and depth to meet higher oxygen demands and remove carbon dioxide efficiently.