Lung Trivia Quiz Questions With Answers

Trivia quiz questions with answers about the human lung.

Lung Trivia Quiz Questions With Answers

What are lungs?
A: The lungs are the primary organs of the respiratory system in humans and many other animals including a few fish and some snails.

Humans have how many lungs?
A: 2, a right lung and a left lung.

They are situated where?
A: Within the thoracic cavity of the chest.

Which lung is bigger?
A: The right lung is bigger than the left.

Which lung shares space in the chest with the heart?
A: The left lung.

The lungs together weigh approximately how much?
A: 1.3 kilograms (2.9 lb), and the right is heavier.

The lungs are part of the lower respiratory tract that begins where?
A: At the trachea and branches into the bronchi and bronchioles.

Together, the lungs contain approximately how many miles of airways?
A: 2,400 kilometres (1,500 mi).

How many alveoli?
A: 300 to 500 million.

Each lung is enclosed within a pleural sac which allows the inner and outer walls to what?
A: Slide over each other whilst breathing takes place, without much friction.

This sac also divides each lung into sections called what?
A: Lobes.

The right lung has how many lobes?
A: Three lobes.

How many does the left lung have?
A: Two.

The lobes are further divided into what?
A: Bronchopulmonary segments and lobules.

The tissue of the lungs can be affected by a number of diseases, including what?
A: Pneumonia and lung cancer.

Chronic obstructive pulmonary disease includes chronic bronchitis and what?
A: Emphysema.

In embryonic development, the lungs begin to develop as an outpouching of the foregut, a tube which goes on to form what?
A: The upper part of the digestive system.

The lungs are conical in shape with a narrow rounded apex at the top, and a broad concave base that rests on the convex surface of the what?
A: Diaphragm.

The left lung shares space with the heart, and has an indentation in its border called what?
A: The cardiac notch.

The front and outer sides of the lungs face the what?
A: The ribs, which make light indentations on their surfaces.

Both lungs have a central recession called the hilum at the root of the lung, where what happens?
A: The blood vessels and airways pass into the lungs.

The lungs are surrounded by what?
A: The pulmonary pleurae.

The right lung has what?
A: Both more lobes and segments than the left.

The entire lower respiratory tract including the trachea, bronchi, and bronchioles is lined with what?
A: Respiratory epithelium.

This is a ciliated epithelium interspersed with goblet cells which produce what?
A: Mucus, and club cells with actions similar to macrophages.

Incomplete rings of cartilage in the trachea and smaller plates of cartilage in the bronchi do what?
A: Keep these airways open.

The alveolar macrophages have an important what?
A: Immunological role.

They remove substances which deposit in the alveoli including what?
A: Loose red blood cells that have been forced out from blood vessels.

The trachea receives air from the pharynx and travels down to a place where it splits (the carina) into what?
A: A right and left bronchus.

Oxygen breathed in, diffuses through the walls of the alveoli into the enveloping capillaries and into the circulation and carbon dioxide does what?
A: Diffuses from the blood into the lungs to be breathed out.

Estimates of the total surface area of lungs are what?
A: About 50 to 75 square metres (540 to 810 sq ft), roughly the same area as one side of a tennis court.

Air is warmed to 37 °C (99 °F), humidified and cleansed by what?
A: The conducting zone.

Particles from the air are removed by the what?
A: Cilia on the respiratory epithelium lining the passageways.

Pulmonary stretch receptors in the smooth muscle of the airways initiate a reflex known as the Hering–Breuer reflex that prevents the lungs from what, during forceful inspiration?
A: Over-inflation.

The lungs have a dual blood supply provided by what?
A: A bronchial and a pulmonary circulation.

The bronchial circulation supplies oxygenated blood to what?
A: The airways of the lungs.

There are usually how many arteries?
A: Three, two to the left lung and one to the right.

Where does the pulmonary circulation carry deoxygenated blood?
A: From the heart to the lungs and returns the oxygenated blood to the heart to supply the rest of the body.

What is the blood volume of the lungs?
A: It’s about 450 milliliters on average, about 9 per cent of the total blood volume of the entire circulatory system.

The lungs are supplied by nerves of the what?
A: The autonomic nervous system.

Input from the parasympathetic nervous system occurs via what?
A: The vagus nerve.

The action of breathing takes place because of nerve signals sent by the respiratory centres in the brainstem, along the phrenic nerve to what?
A: The diaphragm.

At birth, the baby's lungs are filled with fluid secreted by the lungs and are what?
A: Not inflated.

After birth the infant's central nervous system reacts to the sudden change in what?
A: Temperature and environment.

This triggers what?
A: The first breath, within about 10 seconds after delivery.

After the first breath, the fluid in the lungs is quickly what?
A: Absorbed into the body or exhaled.

At birth the lungs are very undeveloped with only around one sixth of the what?
A: The alveoli of the adult lung.

The alveoli continue to form into what?
A: Early adulthood.

The lungs are not capable of expanding to breathe on their own, and will only do so when there is an increase in the volume of what?
A: The thoracic cavity.

This is achieved by the muscles of respiration, through the contraction of the what?
A: The diaphragm, and the intercostal muscles which pull the rib cage upwards.

During breathing out the muscles relax, returning the lungs to what?
A: Their resting position.

The lungs possess several characteristics which protect against what?
A: Infection.

The respiratory tract is lined by what?
A: Epithelia with hair-like projections called cilia that beat rhythmically and carry mucus.

This mucociliary clearance is an important defense system against what?
A: Air-borne infection.

The dust particles and bacteria in the inhaled air are caught in the mucosal surface of the airways, and are moved up towards the pharynx by what?
A: The rhythmic upward beating action of the cilia.

The lining of the lung also secretes immunoglobulin A which does what?
A: Protects against respiratory infections.

In addition, the lining of the lung also contains macrophages, immune cells which do what?
A: Engulf and destroy debris and microbes that enter the lung in a process known as phagocytosis.

The lungs are involved in maintaining homeostasis, helping in the regulation of what?
A: Blood pressure as part of the renin–angiotensin system.

The lungs are involved in the blood's acid-base homeostasis by doing what?
A: Expelling carbon dioxide when breathing.