diving response 1

Question 1

How do hydrostatic pressure and water temperature affect the body during diving?

Answer 1

Hydrostatic Pressure: The deeper you dive, the greater the pressure on the body, affecting gas volumes and circulation.

Water Temperature:

Cooler water can alter metabolism, slowing physiological processes.

Causes peripheral vasoconstriction, reducing blood flow to the extremities to preserve core temperature.

Question 2

hat happens to the body and gases as you go deeper in the ocean?

Answer 2

Pressure increases with depth, compressing air spaces in the body (lungs, sinuses, ears).

Gas volumes decrease according to Boyle’s Law.

Water temperature drops, causing slower metabolism and peripheral vasoconstriction.

Physiological risk: Deep dives increase the risk of lung squeeze and oxygen-related issues.

Question 3

What does Boyle’s Law state, and why is it important for diving?

Answer 3

Boyle’s Law: At constant temperature, gas volume varies inversely with pressure.

Pressure doubles → volume halves.

Pressure halves → volume doubles.

Diving implication: During ascent, expanding gases must escape through the nose or mouth; otherwise, lungs can rupture from the expanding air.

Particularly critical in SCUBA diving, where compressed air expands rapidly as divers ascend.

Question 4

How does Boyle’s Law limit diving depth and affect the body?

Answer 4

Answer: Diving depth is limited because increasing pressure compresses the chest and lungs, restricting blood accumulation and lung expansion.

Explanation: Under hyperbaric conditions, the chest deforms due to pressure. This sets physical limits on how much blood can be centralized and prevents overexpansion of gases, protecting the lungs from injury.

Question 5

What are the possible lung outcomes from excessive pressure on the chest during apnea?

Answer 5

Alveolar collapse (atelectasis) – complete or partial collapse of lung or lobe.

Fluid infiltration – liquid from capillaries enters airways and alveoli.

Alveolar-capillary membrane disruption – bleeding into alveolar spaces.

Question 6

What is Henry’s Law and why is it important in diving?

Answer 6

Answer: At constant temperature, the amount of gas dissolved in a liquid is directly proportional to its partial pressure and solubility.

Explanation: In diving, this explains why more nitrogen dissolves in the blood and tissues at depth. Rapid ascent can cause the dissolved gas to form bubbles, leading to decompression sickness (“the bends”).

Question 7

What happens to your lungs and oxygen when you dive down and then ascend?

Answer 7

Descent: Increased water pressure compresses the lungs, oxygen is more concentrated, and the urge to breathe may be reduced.

Ascent: Pressure decreases, trapped air expands, and failing to exhale can damage lungs.

Question 8

What are the risks of expanding air in the lungs during ascent?

Answer 8

Pneumothorax – lung rupture from overexpansion.

Arterial gas embolism (AGE) – nitrogen bubbles enter the bloodstream, blocking blood vessels.

Cerebral arterial gas embolism (CAGE) – bubbles reach the brain, causing serious neurological damage.

Question 9

How can divers reduce the risks of arterial gas embolism and decompression sickness?

Answer 9

Arterial gas embolism: Avoid breath-holding, rapid ascent, and diving with pulmonary disease or infection.

Decompression sickness: Reduce exposure to inert gases, use higher oxygen concentrations, and follow a decompression schedule with stops (typically every 3 m) during ascent.

Question 10

What is the difference between arterial gas embolism (AGE) and decompression sickness (DCS), and how are they prevented?

Back (Answer/Explanation):

Answer 10

Arterial Gas Embolism (AGE):

Cause: Expanding air ruptures alveoli; bubbles enter arteries.

Trigger: Breath-holding or rapid ascent.

Onset: Immediate after ascent.

Prevention: Avoid breath-holding, rapid ascent, and diving with pulmonary disease.

Decompression Sickness (DCS):

Cause: Dissolved inert gases (e.g., nitrogen) form bubbles in tissues/blood.

Trigger: Staying too long at depth or ascending too quickly.

Onset: Minutes to hours after ascent.

Prevention: Follow decompression schedules, ascend slowly, use safety stops, and reduce inert gas load.

Question 11

How does snorkel design affect breathing and tidal volume?

Answer 11

Answer: A snorkel increases pulmonary deadspace, so you must increase tidal volume to access fresh air effectively.

Question 12

How does hydrostatic pressure affect breathing as a diver descends?

Answer 12

Answer: Increased hydrostatic pressure compresses the chest, making it harder for the inspiratory muscles to expand the lungs.

Explanation:

As a diver descends, water pressure pushes against the chest cavity.

At sufficient depth, the external pressure exceeds the strength of the inspiratory muscles, limiting tidal volume and gas exchange.

This is a key factor in deep diving physiology and can restrict how much oxygen is inhaled.

ydrostatic pressure is the pressure exerted by a fluid (water) at a given depth. The deeper you go, the higher the hydrostatic pressure on your body.

Question 13

What are the main components of the mammalian dive response?

Answer 13

Answer: The dive response includes:

Apnea – voluntary or reflexive cessation of breathing

Bradycardia – slowed heart rate mediated by the parasympathetic nervous system

Peripheral vasoconstriction – reduced blood flow to the extremities via the sympathetic nervous system

Splenic contraction – releases red blood cells to increase oxygen-carrying capacity

Question 14

This reflex is
triggered by the
innervation of the
_________ nerve

Answer 14

Trigeminal nerve (cranial nerve V)