Space Medicine Flashcards
The ___________ line, at an altitude of 62 miles (100 Km) above sea level marks the transition from Earth’s atmosphere to outer space. It is around this altitude that the thinness of the atmosphere does not support aerodynamic lift, thus vehicles will have to transition to reaction thrust to maintain control and keep the weight of the vehicle aloft.
Karman line
At the current time, commercial space pilots are required to maintain a ___________class medical certificate administered by the FAA.
Second class certificate.
The main physiologic stressors for participants of future commercial space flights are velocity and acceleration. A commerical space flight participant will have to re-enter the atmosphere, decelerate, and land. Acceleration forces are best tolerated when the direction (vector) of acceleration or deceleration is _____________.
Through the chest (Gx- front to back, back to front) (eyes in, eyes out).
Space motion sickness can occur with the first 72 hours and affect upward of _______ percent of astronauts.
66-70%
When experienced during the first flight, there is a _______ percent of getting space motion sickness on the second flight.
77%
The most serious threat to health on long-duration, exploration class spaceflight missions is which of the following?
a) Cardiovascular deconditioning
b) Bone loss
c) Radiation exposure
d) Space motion sickness
C) Radiation exposure
Echocardiography data shows a short-term change during the first 17 days of spaceflight of an increase in stroke volume by _____ %. Followed by a decrease of _________ percent at 1, 3, and 5 months.
46%.
10-16%.
Postflight orthostatic intolerance occurs in _____ to ________ of the crew.
20 to 67%
Astronauts height changes by as much as ________ on orbit.
5 to 6cm.
Which of the following is NOT a measure used in the space shuttle program to mitigate the risk of orthostasis upon return to Earth?
a) loading with isotonic fluid prior to re-entry
b) extended G-suit inflation
c) flight deck crew seats reclined 30 degrees
d) mandatory exercise during extended missions
e) Use of cooling garments
c) flight deck crew seats reclined to 30 degrees
In the microgravity environment atmospheric particle count is:
a) decreased due to lack of convection
b) decreased because the heavier particles settle out
c) about the same as in a 1-g operating room
d) increased due to lack of gravity
e) none of the above
d) increased due to lack of gravity
Toxic exposures in the space shuttle are LEAST likely to be caused by:
a) crew metabolic products
b) hydrazine
c) non-metallic particles
d) payload chemicals
e) metals
e) metals
Galactic Cosmic Radiation:
a) consists mostly of electons and high energy nuclei of heavier atoms
b) is of little consequence within spacecraft, but may be harmful during EVA’s.
c) consists of about 79% protons, and 20% helium nuclei (alpha particles)
d) at sea level has only 40% of ionizing power it has at 70,000 feet.
c) Consists of 79% protons and 20 % alpha particles
One gray (GY) is the amount of radiation absorbed by the body quantified as___________.
one joule of energy absorbed per kilogram of body mass
Space station atmosphere is:
14.7 or sea level atmosphere
Theories on the etiology of space motion sickness include all EXCEPT:
a) gastrocolic distention
b) cephalad fluid shift
c) Treisman’s theory
d) Sensory conflict
e) otolith asymmetry
a) gastrocolic distention
The excretory products of man which contribute to the gaseous pollution of the artificial gaseous atmosphere (AGA) in the spacecraft are released into the spacecraft from____________.
Lungs, hair, skin, GI tract, urinary tract, and mouth
Ebullism or the boiling of body fluids occurs at an altitude known as _______________.
Armstrong’s Line- 63,000 feet
Von Karman’s line is at 62 miles where the atmosphere gives way to outer space.
What is the purpose of ozone?
Ozone is formed when ultraviolet light around 2000 angstroms is absorbed by O2. Maximum concentration is found at 30 Km. Destruction of ozone by UV between 2100 and 2900 angstroms raises air temperature to a maximum of 35 degrees at a height of 50 Km. The primary biologic effect is the absorption of harmful UV light below 3000 angstroms, NOT cosmis ray attenuation.
Inflight monitoring of the electrical activity of the heart revealed arrhythmias in the crew of the Apollo 15. These arrhythmias were a result of:
a) dehydration
b) hypoxia
c) potassium deficit
d) zero gravity
c) potassium deficit
Animal and human experiments on the effects of ambient temperature on the physiologic response to acceleration have shown what?
That high temperatures reduce, and low temperatures increase the body’s resistance to accelerations.
The gas or compounds that protect the earth from UV radiation below 3000 angstroms is/are:
a) oxygen
b) ozone
c) carbon dioxide
d) water vapor
e) a and b
e) a and b. Both oxygen and ozone protect the earth from UV radiation below 3000 angstroms.
The greatest physiologic danger to manned orbital flights at distances of 500 to 50,000 miles from the earth’s surface is:
a) decreasing body weight and decreasing gravity
b) increasing temperature
c) decreasing temperature
d) increasing particle radiation
d) increasing particle radiation
When loss of a protective shield and failure of deployed solar panels caused Skylab to heat up to 130 degrees, what unique thermal risk faced the first manning crew?
Absence of convective cooling. The lack of gravitational gradient produces atmospheric stasis, allowing no natural convection currents.
