Form 3 Science: Human Respiration

Vocabulary flashcards covering the human respiratory system based on the provided Science Form 3 lecture notes.

Respiration

The process of releasing energy from food.

Primary Respiratory Organ

The lungs.

Pathway of Air (Inhalation)

Nose -> trachea -> bronchus -> bronchiole -> alveolus.

Function of the Nose

To filter, warm, and moisten air.

Nasal Hair

Filters dust and foreign particles.

Mucus

A substance in the respiratory tract that traps dust and microorganisms.

Cilia

Small hair-like structures that push mucus and foreign particles out of the respiratory tract.

Trachea

The tube that carries air to the bronchus.

Cartilage Rings

Ensure that the trachea remains open.

Bronchus

The two main branches that the trachea divides into.

Bronchiole

A small branch leading from the bronchus.

Alveolus

Small air sacs inside the lungs.

Function of the Alveolus

The site of gas exchange.

Gas Diffusion (Alveolus to Blood)

Oxygen.

Gas Diffusion (Blood to Alveolus)

Carbon dioxide.

Gas Exchange Mechanism

Diffusion.

Thin Alveolar Walls

Facilitate the diffusion of gases.

Large Surface Area (Alveolus)

Increases the rate of gas exchange.

Capillary Network

Surrounds the alveolus to speed up gas exchange.

Main Respiratory Muscles

The diaphragm and intercostal muscles.

Diaphragm (Inhalation)

Contracts and flattens.

Rib Cage (Inhalation)

Moves upwards and outwards.

Thoracic Cavity Volume (Inhalation)

Increases.

Lung Air Pressure (Inhalation)

Decreases.

Diaphragm (Exhalation)

Relaxes and curves upwards.

Rib Cage (Exhalation)

Moves downwards and inwards.

Thoracic Cavity Volume (Exhalation)

Decreases.

Lung Air Pressure (Exhalation)

Increases.

Effect of Smoking

Damages the lungs and affects breathing.

Smoking-related Respiratory Diseases

Lung cancer, emphysema, or bronchitis.