Physiology

Question 1

oxygen is transported efficiently throughout the body because of a substance called ______ contained in the _____

Answer 1

Hemoglobin. Red blood cells

Question 2

_______is the fluid in which all the components in blood are suspended.

_____ comprise ____% of the blood mass

Answer 2

Plasma

Red blood cells

45%

Question 3

Without hemoglobin blood would have to circulate 15-20 times faster to transport oxygen to keep up with body? T/F

Answer 3

True

Question 4

Large amounts of CO2 can be carried by the circulatory system back to the lungs for expiration primarily because ______

Answer 4

Can be converted into bicarbonate

Question 5

You breathe deeply in scuba diving in order to compensate for the
A) increased dead air spaces resulting from snorkel and regulator
B) reduced lung volume from compression of chest
C) increased amount of alveolar CO2 due to increased resistance of breathing while submerged

Answer 5

A, B , C

Question 6

You breathe slowly when scuba diving because
A) minimize resistance caused by turbulence in the airways
B) compensate for the decrease in energy from cold water
C) avoid potential for thoracic squeeze

Answer 6

A

Slower breathing reduces turbulence. Turbulence results in increased resistance and therefore increased effort

Question 7

When a breathe hold diver immerses his _____ in cold water his heart rate _____

Referred to as the _______ diving reflex, which is common to all diving mammals.

Answer 7

Head
Decrease
Mammalian

Question 8

To reduce the demand for O2 while breath holding diving the diver should
A) take a few rapid deep breathes before diving
B) take lots of rapid breathes before diving
C) move slowly and deliberately underwater
D) breathe pure O2

Answer 8

C

Question 9

Breathing slowly from the diaphragm before a dive can
A) promote relaxation
B) promote better gas exchange
C) reduce dead air volume

Answer 9

All

Question 10

Breathing is regulated based on the amount of _____ in the blood

Answer 10

CO2

Question 11

The urge to breathe is suppressed because of the low level of oxygen in breath holding diving? T/F

Answer 11

False CO2

Question 12

In breath holding diving if the tissues continue to be air starved they begin to cease functioning and the diver loses consciousness due to lack of CO2? T/F

Answer 12

False loose consciousness due to lack of Oxygen even though lack of CO2 caused the issue initially

Question 13

Hypoxia results when the diver’s CO2 can’t accumulate to a level high enough to stimulate breathing before the tissues consume available oxygen? T/F

Answer 13

True

Question 14

Blackout on ascent occurs because the _____ ______ of the alveolar ______ rapidly decreases

Answer 14

Partial pressure O2

Question 15

Hyperventilating at the surface prior to a breath hold dive reduces the level of ____

Answer 15

CO2

Question 16

The carotid- sinus receptors, which are located in the carotid arteries stimulate the ____ ____ _____ which is located in the _____

Answer 16

Cardio inhibitory center. brain

Question 17

If the neck seal of your dry suit is too tight it could cause the carotid sinus reflex causing heart rate to decrease/increase because the brain thinks the blood pressure is to low/high

Answer 17

Decrease high

Question 18

Carbon monoxide is ____ and _____ which makes it hard to detect

Answer 18

Odorless. Tasteless

Question 19

Carbon monoxide bonds with hemoglobin ____ times more readily than _____ and can take _____ hours for the circulatory system to eliminate

Answer 19

200
Oxygen
8-12 hours

Question 20

Symptoms of carbon monoxide not as noticeable at _____ because high levels of _____ are dissolved in the ______ allowing tissues to meet their _____ requirement

Answer 20

Depth. Oxygen. Plasma. Oxygen

Question 21

How can the plasma carry more oxygen at depth?

Answer 21

Because higher partial pressure of oxygen

Question 22

Smoking cigarettes prior to diving can raise the ____ _____ level _____ times above normal which impairs _____ transport and _____ elimination

Answer 22

Carbon monoxide. 3-12. Oxygen. Carbon Dioxide

Question 23

Carbon monoxide locks up the ____ in the blood impairing the transport of _____ and elimination of _______

Answer 23

Hemoglobin. Oxygen. Carbon Dioxide

Question 24

Factors that cause body tissues to absorb and eliminate nitrogen at different rates
A) high or low blood supply
B) distance from skin surface
C) tissue density
D) distance from lungs

Answer 24

A C

ie bone denser than skin; density effects how gas is focused when reaches the skin

Blood supply differs among tissues; more blood supply will have more gas delivered and eliminated

Question 25

Bubble formation cannot occur until the tissues become _______

Answer 25

Supersaturation

Question 26

Supersaturation cannot occur until the ambient pressure is _______ upon ______

Answer 26

Reduced. Ascent

Question 27

You can get DCS if you stay at a depth indefinitely? T/F

Answer 27

False, you can remain at depth indefinitely

Question 28

Decompression sickness occurs upon surfacing rather than at depth because ______ does not occur in body tissues until the ambient pressure is reduced

Answer 28

Supersaturation

Question 29

Any amount of supersaturation results in significant bubble formation?T/F

Answer 29

False Otherwise gets DCS going to top of skyscraper

Question 30

Factors increasing susceptibility to DCS A) tissue half times B) physical conditioning C) changes to respiration D) changes to circulation

Answer 30

B D

Question 31

We can only control which factor that effects gas absorption?

Answer 31

Amount of blood flow (circulation) Can’t control tissue density

Question 32

Circulation changes in the following ways effecting gas absorption ______ circulation efficiency with age ______ circulation from exercise changes in circulation during ______ consumption Recent _____ or _______

Answer 32

Decreased Increased Alcohol Illness injury

Question 33

Silent bubbles cause signs and symptoms of DCS? T/F

Answer 33

False- Are so small they do not cause signs and symptoms of DCS

Question 34

What device used to detect presence of silent bubbles is it a stethoscope? Y/N

Answer 34

No Doppler Ultrasound Flowmeter

Question 35

A criterion used to test decompression models and some dive tables/computers are the presence of silent bubbles as they travel in venous circulation to the lungs detected with the Doppler Ultrasound Flowmeter? T/F

Answer 35

True

Question 36

Silent bubbles are thought to form because of the presence of ____ _____

Answer 36

Gas seeds (micro nuclei)

Question 37

Why don’t oxygen bubbles cause DCS

Answer 37

Metabolized by body

Question 38

Inert gases are ones such as nitrogen not metabolized by the body? T/F

Answer 38

True

Question 39

In DCS bubbles form because the nitrogen can’t escape quickly enough to remain in solution? T/F

Answer 39

True

Question 40

Whatever nitrogen is absorbed as the ambient pressure ______ must be eliminated as the ambient pressure is _____

Answer 40

Increases. Reduced

Question 41

Why does breathing pure Oxygen help with DCS

Answer 41

It increases the pressure gradient between the tissue nitrogen level and the alveolar nitrogen levels resulting in a significant increase in the driving force of the tissue nitrogen aiding in its elimination

Question 42

If the nitrogen in the tissues is high but low in the alveolar air what happens to the nitrogen

Answer 42

It comes out

Question 43

Narcosis results from disruptions in ______ impulses transmissions. _____ gases particularly when breathed under pressure have the capacity to cause this disruption. Can Oxygen or CO2 cause gas narcosis?

Answer 43

Nerve. inert Yes

Question 44

Nitrogen has no effect at surface pressure but when breathed under sufficient pressure can cause disruption of nerve impulses? T/F

Answer 44

True

Question 45

The degree of disruption from narcosis depends on how well the gas dissolved into the lipid? T/F

Answer 45

True

Question 46

Gas narcosis signs and symptoms typically begin at _____. Yet many divers have succumbed much shallower particularly where _____ or ____ have been consumed.

Answer 46

30m/100’ Drugs. Alcohol

Question 47

What are signs and symptoms of gas narcosis?

Answer 47

Poor judgement Decreased coordination A feeling of false security Others include foolish behavior, anxious or uncomfortable feelings and a general disregard for safety

Question 48

Barotrauma means

Answer 48

Pressure injury

Question 49

An excessively forceful Valsalva maneuver could cause a _____ _____ rupture or rupture of your ___ ___

Answer 49

Round window Ear drum

Question 50

Severe lung squeeze could result if a skin diver descends with his lungs nearly ____

Answer 50

Empty Could result in severe tissue damage and bleeding

Question 51

Squeezes take place on _____ whereas reverse squeezes take place on _____

Answer 51

Descent. Ascent

Question 52

Vertigo can be caused by A) ear squeeze B) inner ear barotrauma C) decompression sickness

Answer 52

All

Question 53

Sound vibrations transferred from the outer ear to inner ear via

Answer 53

Ossicles

Question 54

Series of bones attached at one end of tympanic membrane (ear drum)

Answer 54

Ossicles

Question 55

Ossicles are connected to the ____ _____ of the inner ear

Answer 55

Oval window

Question 56

Vestibular canals (semi circular canals) are located in the ____ ____ and are responsible for _____

Answer 56

Inner ear. Balance

Question 57

Movement of air in the vestibular canals can be interpreted by the brain to determine balance and orientation? T/F

Answer 57

False - movement of fluid in canals

Question 58

Portion of ear most effected by pressure changes Why not the others

Answer 58

Middle ear Inner ear not because fluid filled Outer ear not because open to the water

Question 59

Symptom of air embolism may be sudden ____ while two symptoms of decompression sickness may be ____ ____ _____ ______ and _____

Answer 59

Sudden Unconsciousness Pain in the joints and fatigue

Question 60

In an air embolism air bubbles are transported into the pulmonary vein then to the heart and then most likely to the brain? T/F

Answer 60

True

Question 61

Air embolism- air bubbles block arterial circulation when too numerous to pass through the blood vessels? T/F

Answer 61

False - too large

Question 62

Decompression sickness from nitrogen elimination occurring so quickly that it comes out of solution and forms bubbles? T/F

Answer 62

True

Question 63

Decompression sickness occurs immediately/over time

Answer 63

Over time (usually 30 minutes or more)

Question 64

In terms of symptom location, air embolism is characterized by one/both sides of body whereas decompression sickness is characterized by one/both sides of the upper or lower body

Answer 64

Air embolism- one side of body like a stroke; entire right or left side effected DCS- both sides upper or lower, like paralysis when involves CNS, depends on where bubble damage is in spinal cord

Question 65

In terms of change of symptoms, air embolism is characterized by improvement/worsening/neither from first aid while DCS is characterized by improvement/worsening/neither from first aid

Answer 65

Improvement of symptoms for AGE No change for DCS with first aid as condition requires time to develop and therefore requires time and aggressive treatment to improve

Question 66

The most serious form of lung overexpansion injury is an _____ Why

Answer 66

AGE Air Bubbles enter arterial circulation (similar to stroke) block blood flow; bubbles usually migrate to brain and expand as diver ascends

Question 67

When breathing normally could a diver suffer from a lung over expansion injury? Y/N

Answer 67

Yes - any obstruction can cause over pressurization, including one deep in the lungs caused be asthma and other pulmonary disorders.

Question 68

A more prevalent cause of lung obstructions in divers are those resulting from ______ or diving after having a severe ____ _____.

Answer 68

Smoking Chest cold

Question 69

Surfactant is a substance that coats the inner surfaces of ____ and ______ help prevents them from ______

Answer 69

Bronchioles and alveoli Collapasing

Question 70

_____ ______ destroys the _____ in bronchioles and alveoli, which inhibits their reopening

Answer 70

Smoking cigarettes Surfactant

Question 71

During exhalation the bronchioles and alveoli _____ because of their size and flexibility

Answer 71

Collapse

Question 72

There are higher than normal CO2 levels in the alveoli when diving brought about by the increased resistance of breathing while submerged? T/F

Answer 72

True

Question 73

Turbulence causes breathing to become more/less difficult which is why you should breathe slowly/quickly

Answer 73

More Slowly

Question 74

An AGE usually occurs within the ____ ____ ______whereas DCS tends to be _____ usually more than _____ minutes after the dive.

Answer 74

First five minutes Delayed 30

Question 75

Most common symptom of AGE vs DCS

Answer 75

Sudden unconsciousness Pain in joints, fatigue

Question 76

When administering O2 to someone with DCS you have them

Answer 76

Lay on left side with head low??? (Rainbow reef) Or Lay flat (PADI)

Question 77

Too much CO2 in the blood is known as

Answer 77

Hypercapnia

Question 78

Skin divers use ____ to increase breath hold times by reducing the level of CO2 in lungs

Answer 78

Diaphragmatic breathing

Question 79

When diving in a current a poorly adjusted regulator may cause a diver to A) become over exerted B) have excessive CO2 build up C) have labored shallow breathing

Answer 79

All