Physiology

Question 1

What are cones in the eye used for?

Answer 1

Colour and acuity

Question 2

What are rods in the eye used for?

Answer 2

Seeing at night/dusk.
Detecting light intensity
Peripheral vision

Question 3

Why can’t we look directly at objects at night?

Answer 3

The fovel centratils only has cones, no rods

Question 4

How do we look at items at night?

What do we do differently from day?

Answer 4

We use our prepherial vision, so need to look to the side.

Question 5

How long does it take for eyes to adjust at night

Answer 5

Rods take 20-30 minutes to adapt

Question 6

How long do cones take to adjust

Answer 6

Cones adapt in 6-8 minutes

Question 7

What is the most important sense?

Answer 7

Vision

Question 8

What senses motion?

For the body

Answer 8

Inner ear ( vestibular system )

Question 9

What is the sclera?

Answer 9

It gives the eye its form. Outside the retina

Question 10

What is the cornea?

Answer 10

The cornea is the transparent part of the sclera

Question 11

What is the iris?

Answer 11

It controls the amount of light allowed into the eye

Question 12

What is the lens?

Answer 12

The lens is used to focus the eye.

Question 13

What are cones?

Answer 13

Cones detect colour
Cones provide visual acuity

Question 14

Where are rods and cones concentrated?

Answer 14

Cones in the Macula.
Rods in on the edges

Question 15

What is empty field myopia

Answer 15

Eyes will focus at default ( 3 to 4m )
Pilot will think they are looking outside, they only see the front of the plane.

Question 16

What is the recommended scanning rate

Answer 16

No more than 10 degrees per second

Question 17

How long is our reaction time when looking?

Time between seeing and doing something

Answer 17

About 1 1/2 seconds

Question 18

What is perception?

Answer 18

Organisation, identification and interpretation of sensory information.
It has a lot of baises

Question 19

What are the limitations of a mental model?

Answer 19

Founded on incomplete facts
Is flexible - both in a positive and negative way
Is limited compared to actual world

Question 20

What is bottom up processing?

Answer 20

Sensory information going directly to the brain. No thinking required

Question 21

What is top down processing?

Answer 21

Using top down to make sense of the world. E.g relative sizes of things to decide what is closer.

Question 22

What decreases or increases the amount of attention needed?

Answer 22

Pre-existing knowledge - requires less attention
Talking - requires attention

Question 23

What is working memory?

Answer 23

Short term memory.
Fills up quickly and easily wiped.

Question 24

What is long term memory?
What is the main problem?

Answer 24

Important information is held here.
Problem is retrieval

Question 25

What is the cause of motion sickness?

Answer 25

Slow unfamiliar movements Mismatch of sensory inputs

Question 26

What is the gas mix in the atmosphere ?

Answer 26

1% other 21% Oxygen 78% Nitrogen

Question 27

Cause of air sickness ( and how address them )

Answer 27

Slow or slight movements you are unfamiliar with To fix: - look outside at a fixed point.

Question 28

What is the rapid eye movement between fixed points called?

Answer 28

Nystagamus

Question 29

What is partial pressure?

Answer 29

Pressure of a single gas in the atmosphere.

Question 30

Action coping, cofniative coping, symptom directive coping

Answer 30

**Action Coping** - Taking action, for example talking to someone who is causing stress. **Cognitive coping** - taking mental steps to avoid stress, based on perception. However, may not always be addressing the root cause ( for example suppression or avoidance ) **Symptom Directive Coping** - Using drugs or alcohol, excessive exercise. To 'take your mind off it'

Question 31

What is the decrease in temp as we increase altitude

Answer 31

Approximately 2 degrees c Per 1000 feet

Question 32

How does altitude increase affect our lungs the ability to absorb oxygen?

Answer 32

Results in a lower pressure of air, therefore lower partial pressure and lower water saturated partial pressure **Sealevel ** Air 760 mmHG PO2 159 PAO2 103 **10,000 Ft ** Air 523 PO2 109 PAO2 61

Question 33

Difference between acute and chronic fatigue

Answer 33

Acute - normal and short term Chronic - caused by prolonged stress. When it becomes serious enough it leads to emotional illness

Question 34

Symptoms of Hypoxia

Answer 34

Fuzziness of the head or thick feeling slow of thought and poor judgement failing memory clumsiness Feeling of euphoria Mental fixation on unimportant tasks visual changes quick breathing extremities turn blue due to reduced O2

Question 35

How does Carbon Dioxide posioning work?

Answer 35

It combines with haemgoblin to create carboxyhaemoglobin - which takes space for haemoglobin.

Question 36

Treatments for Hyperventilation

Answer 36

Slow down breathing Breathe into paper bag ( to build up CO2 levels ) 100% oxygen ( when at altitude )

Question 37

How do the Right / Left Heart flows work

Answer 37

Right Heart -> Lungs -> Left Heart -> Body -> Right Heart

Question 38

What do veins and arteries do

Answer 38

Veins carry blood *to* the heart Arteries carry blood *away* from the heart ( Thats why killers cut arteries )

Question 39

What does the respitroy system do?

Answer 39

Provides O2 and removes COs

Question 40

What does the cardiovascular system do?

Answer 40

Transports Blood and therefore Oxygen to organs.

Question 41

What happens if outside pressure = body fluid pressure?

Answer 41

Blood will boil ( i.e in space without a spacesuit )

Question 42

One unit of Alcohol is for: Spirits Beer Wine

Answer 42

Spirits - 2.5cl ( 1 measure ) Beer - 28cl ( 1/2 pint ) Wine - 12cl (1 glass )

Question 43

Describe how the Vestibule System works

Answer 43

*Detects Linear Motion* Utricle - Horizontal Saccule - Vertical One is in each side of the head Has gel like substances ( membrane and stones ) Cilla detect linear motion

Question 44

Describe how the Semicircular canals work

Answer 44

3 tubes on each axis Fluid called Endolypmh. Stationary in base is the Ampulla Ampulla has cilla to detect deformity As the fluid moves, the Ampulla gets deformed and acceleration is detected.

Question 45

Describe parts of the eye

Answer 45

Lens - clear Sclera - gives shape Corena - transparent part of the Sclera Iris - for light control Rods - light intensity Cones - colour and acuity Retina - lining - detects light Optic Nerve - back to brain - blind spot

Question 46

Which organ is least likely to affected by pressure changes?

Answer 46

Lungs ( due to their large size )

Question 47

What is barotrauma?

Answer 47

Differences in pressure in cavities in the body. E.g Ear. The Valsalva manouver is used ( pitch nose ) for this case. Avoid canned and presurised drinks before flying

Question 48

What are the stages of G Force?

Answer 48

Grey Out Black out (Red out if inverted ) G Loc

Question 49

What are the layers of the atmosphere?

Answer 49

Thermosphere Menosphere Stratasphere Tropopause Troposphere

Question 50

What types of body cavaties are affected by Pressure changes?

Answer 50

Both Closed and Open. Large are less affected ( I.E we dont get lung pains... we get ear pain, teeth pain, joint pain, tummy pain first )

Question 51

how long after diving can you fly?

Answer 51

If going above 8,000ft Scuba - no decompression stops 12 Hours Scuba - decompression stops 24 hours

Question 52

Treatment if someone has been diving

Answer 52

100% Oxygen Emergency Descent Even 500ft could be fatal Do not move joints to help

Question 54

Describe the 3 rotation effects

Answer 54

Centrigual - sending us outwards Centripedal - counter to centrifugal Coriolis - caused by rotation of the earth ( we will seem to head left when flying north )