MGRADES
IB SEHS Topic 1, 2 & 3 Review UPDATED
ACTUAL Exam Questions and CORRECT
Answers
Oxygen uptake/VO2 - CORRECT ANSWER - the amount of oxygen taken into the body
and used (a good indicator of how well internal systems are working together)
VO2 may be measured to evaluate health and fitness in an individual.
gas exchange - CORRECT ANSWER - the transfer of carbon dioxide and oxygen between
systems
Testing VO2 today - CORRECT ANSWER - Tests of physiological functions used to only
be done for research. Today these tests are done in a variety of ways in a variety of places (ex/
hospitals). This is partly do to technology. (Refer to bike image in textbook as visual).
The process of breathing and how exercise affects this process: - CORRECT ANSWER -
1) Oxygen rich air is inhaled through mouth or nose (this can be voluntary or involuntary). In
order for air to be breathed in, air pressure in the lungs needs to be lower than in the atmosphere.
2) As air is inhaled, the diaphragm pulls downward (w/ the help of other chest muscles) and
increases the volume of the lungs. This volume increase reduces pressure in the lungs causing air
to flow from the atmosphere in to the lungs.
3) No energy is required for exhalation. The lungs recoil and increase in pressure so that air
flows out through the mouth again.
4) During exercise, active muscles need more oxygen, thus inhalation needs to occur at a faster
rate. During exercise, lung size can increase to an even greater volume and chest muscles can
compress the lungs at a faster rate, allowing fast breathing.
Breathing sequence: - CORRECT ANSWER - Air goes through conducting airways (nasal
and oral passage ways, trachea and bronchi), is moistened by the airway linings, goes to the
smaller bronchi branches and eventually end up in small air sacs called alveolus. Gas exchange
takes place here (where Oxygen and Carbon dioxide enter the blood).
,MGRADES
(Nolan Makes Pumpkin Lattes To Be (a) Barista Like Andrew)
Stands for: Nasal cavity, pharynx, larynx, trachea, bronchi, bronchioles, lungs, alveoli.
lungs have... - CORRECT ANSWER - A very large surface area, good blood supply, and
the distance between blood and the alveoli is very thin.
diffusion - CORRECT ANSWER - where gas will move along a gradient from an area of
higher partial pressure to a lower partial pressure.
partial pressure - CORRECT ANSWER - represents the pressure exerted by a single gas
O2 and CO2 as they diffuse in the lungs - CORRECT ANSWER - Air breathed into the
lungs is high in oxygen and low in carbon dioxide. Blood being pumped via the heart to the
lungs is low in oxygen and higher in carbon dioxide. Therefore, oxygen will diffuse from the
alveolus in the lungs across the pressure gradient into the blood while carbon dioxide diffuses
from the blood through the pressure gradient into the alveolus. (The opposite occurs when
oxygen is being transferred to different muscles and parts of the body for use).
Pressure gradients during exercise - CORRECT ANSWER - During exercise, the pressure
gradient at the tissues and lungs becomes greater as more oxygen is being used up and more
carbon dioxide is being produced. The challenge for the lungs is to maintain resting partial
pressures in the alveoli. This is achieved by breathing out the air with less oxygen and more
carbon dioxide and then breathing in fresh air to maintain the pressure gradients for diffusion to
occur.
VE - CORRECT ANSWER - (volume exhaled) describes the volume of air being exhaled
per minute
VT - CORRECT ANSWER - tidal volume
BF - CORRECT ANSWER - is breathing frequency (number of breaths)
,MGRADES
Calculation/formula for VE - CORRECT ANSWER - VE=VT(Bf)
volume exhaled= tidal volume x breathing frequency
To maintain resting gas partial pressures in the lungs and arterial blood supply to active tissues...
- CORRECT ANSWER - the volume of air is increase as a result of more breaths and a
greater tidal volume during exercise.
when exercise becomes harder, ventilation_____ - CORRECT ANSWER - increases and
the arterial partial pressure of oxygen is preserved.
Factors that stimulate or inhibit ventilation: - CORRECT ANSWER - These include gas
partial pressures, acidity, temp, and hormones. The contribution of these factors depends on
characteristics of the exercise (ex/ intensity, duration) (ex/ oxygen receptors increase ventilation
when someone is at a high altitude)
hyperventilation - CORRECT ANSWER - the increase in ventilation above what is
actually required to meet oxygen demands. This causes us to breathe out more CO2 and thus our
CO2 levels create less desire for our body to breathe.
main function of blood during exercise - CORRECT ANSWER - to transport materials
(gases, nutrients, waste products, hormones, or heat) to and from tissues.
plasma - CORRECT ANSWER - material that makes up 55% of blood and contains
dissolved substances.
blood composition - CORRECT ANSWER - plasma, red blood cells, white blood cells and
platelets.
platelets - CORRECT ANSWER - These are cell fragments in the white blood cells and
assists in the process of repair following an injury. They form blood clots and prevent (excess)
bleeding.
, MGRADES
white blood cells (leucocytes) - CORRECT ANSWER - Are primarily used in immune
functions and protecting the body from infection. They combat disease possible infections.
red blood cells (erythrocytes) - CORRECT ANSWER - make up 40-45% of blood volume
(which is known as hematocrit). Used mainly for transport of materials (especially
hemoglobin/oxygen).
hemoglobin - CORRECT ANSWER - iron rich pigment in blood that oxygen attaches
itself to in order to be transported. (oxygen attaches to Iron on hemoglobin in the lungs, then
releases by active tissue (muscles)).
arteries - CORRECT ANSWER - Have a large diameter, thick muscular walls, and the
blood exerts a large amount of force on these walls. Responsible for taking blood AWAY from
the heart to bodily tissues.
Easy to remember because Arteries go Away (both "A").
Arteries branch into smaller ________ - CORRECT ANSWER - arterioles
capillaries - CORRECT ANSWER - Are very narrow, have very thin walls, and form the
branching network through tissues where exchange of Oxygen between the blood and tissues
occurs.
___________ thicken to form veins - CORRECT ANSWER - venuoles
veins - CORRECT ANSWER - deliver deoxygenated blood from tissues BACK
(TOWARDS) to the heart. They are less muscular and fiberous than arteries. The pressure in
them is low, they are flexible, and have valves (in the larger veins) that prevent back flow.
Two loops of circulation of blood in the heart - CORRECT ANSWER - 1) Pulmonary
circulation
IB SEHS Topic 1, 2 & 3 Review UPDATED
ACTUAL Exam Questions and CORRECT
Answers
Oxygen uptake/VO2 - CORRECT ANSWER - the amount of oxygen taken into the body
and used (a good indicator of how well internal systems are working together)
VO2 may be measured to evaluate health and fitness in an individual.
gas exchange - CORRECT ANSWER - the transfer of carbon dioxide and oxygen between
systems
Testing VO2 today - CORRECT ANSWER - Tests of physiological functions used to only
be done for research. Today these tests are done in a variety of ways in a variety of places (ex/
hospitals). This is partly do to technology. (Refer to bike image in textbook as visual).
The process of breathing and how exercise affects this process: - CORRECT ANSWER -
1) Oxygen rich air is inhaled through mouth or nose (this can be voluntary or involuntary). In
order for air to be breathed in, air pressure in the lungs needs to be lower than in the atmosphere.
2) As air is inhaled, the diaphragm pulls downward (w/ the help of other chest muscles) and
increases the volume of the lungs. This volume increase reduces pressure in the lungs causing air
to flow from the atmosphere in to the lungs.
3) No energy is required for exhalation. The lungs recoil and increase in pressure so that air
flows out through the mouth again.
4) During exercise, active muscles need more oxygen, thus inhalation needs to occur at a faster
rate. During exercise, lung size can increase to an even greater volume and chest muscles can
compress the lungs at a faster rate, allowing fast breathing.
Breathing sequence: - CORRECT ANSWER - Air goes through conducting airways (nasal
and oral passage ways, trachea and bronchi), is moistened by the airway linings, goes to the
smaller bronchi branches and eventually end up in small air sacs called alveolus. Gas exchange
takes place here (where Oxygen and Carbon dioxide enter the blood).
,MGRADES
(Nolan Makes Pumpkin Lattes To Be (a) Barista Like Andrew)
Stands for: Nasal cavity, pharynx, larynx, trachea, bronchi, bronchioles, lungs, alveoli.
lungs have... - CORRECT ANSWER - A very large surface area, good blood supply, and
the distance between blood and the alveoli is very thin.
diffusion - CORRECT ANSWER - where gas will move along a gradient from an area of
higher partial pressure to a lower partial pressure.
partial pressure - CORRECT ANSWER - represents the pressure exerted by a single gas
O2 and CO2 as they diffuse in the lungs - CORRECT ANSWER - Air breathed into the
lungs is high in oxygen and low in carbon dioxide. Blood being pumped via the heart to the
lungs is low in oxygen and higher in carbon dioxide. Therefore, oxygen will diffuse from the
alveolus in the lungs across the pressure gradient into the blood while carbon dioxide diffuses
from the blood through the pressure gradient into the alveolus. (The opposite occurs when
oxygen is being transferred to different muscles and parts of the body for use).
Pressure gradients during exercise - CORRECT ANSWER - During exercise, the pressure
gradient at the tissues and lungs becomes greater as more oxygen is being used up and more
carbon dioxide is being produced. The challenge for the lungs is to maintain resting partial
pressures in the alveoli. This is achieved by breathing out the air with less oxygen and more
carbon dioxide and then breathing in fresh air to maintain the pressure gradients for diffusion to
occur.
VE - CORRECT ANSWER - (volume exhaled) describes the volume of air being exhaled
per minute
VT - CORRECT ANSWER - tidal volume
BF - CORRECT ANSWER - is breathing frequency (number of breaths)
,MGRADES
Calculation/formula for VE - CORRECT ANSWER - VE=VT(Bf)
volume exhaled= tidal volume x breathing frequency
To maintain resting gas partial pressures in the lungs and arterial blood supply to active tissues...
- CORRECT ANSWER - the volume of air is increase as a result of more breaths and a
greater tidal volume during exercise.
when exercise becomes harder, ventilation_____ - CORRECT ANSWER - increases and
the arterial partial pressure of oxygen is preserved.
Factors that stimulate or inhibit ventilation: - CORRECT ANSWER - These include gas
partial pressures, acidity, temp, and hormones. The contribution of these factors depends on
characteristics of the exercise (ex/ intensity, duration) (ex/ oxygen receptors increase ventilation
when someone is at a high altitude)
hyperventilation - CORRECT ANSWER - the increase in ventilation above what is
actually required to meet oxygen demands. This causes us to breathe out more CO2 and thus our
CO2 levels create less desire for our body to breathe.
main function of blood during exercise - CORRECT ANSWER - to transport materials
(gases, nutrients, waste products, hormones, or heat) to and from tissues.
plasma - CORRECT ANSWER - material that makes up 55% of blood and contains
dissolved substances.
blood composition - CORRECT ANSWER - plasma, red blood cells, white blood cells and
platelets.
platelets - CORRECT ANSWER - These are cell fragments in the white blood cells and
assists in the process of repair following an injury. They form blood clots and prevent (excess)
bleeding.
, MGRADES
white blood cells (leucocytes) - CORRECT ANSWER - Are primarily used in immune
functions and protecting the body from infection. They combat disease possible infections.
red blood cells (erythrocytes) - CORRECT ANSWER - make up 40-45% of blood volume
(which is known as hematocrit). Used mainly for transport of materials (especially
hemoglobin/oxygen).
hemoglobin - CORRECT ANSWER - iron rich pigment in blood that oxygen attaches
itself to in order to be transported. (oxygen attaches to Iron on hemoglobin in the lungs, then
releases by active tissue (muscles)).
arteries - CORRECT ANSWER - Have a large diameter, thick muscular walls, and the
blood exerts a large amount of force on these walls. Responsible for taking blood AWAY from
the heart to bodily tissues.
Easy to remember because Arteries go Away (both "A").
Arteries branch into smaller ________ - CORRECT ANSWER - arterioles
capillaries - CORRECT ANSWER - Are very narrow, have very thin walls, and form the
branching network through tissues where exchange of Oxygen between the blood and tissues
occurs.
___________ thicken to form veins - CORRECT ANSWER - venuoles
veins - CORRECT ANSWER - deliver deoxygenated blood from tissues BACK
(TOWARDS) to the heart. They are less muscular and fiberous than arteries. The pressure in
them is low, they are flexible, and have valves (in the larger veins) that prevent back flow.
Two loops of circulation of blood in the heart - CORRECT ANSWER - 1) Pulmonary
circulation
