BCLN BIOLOGY 12 – Rev July 2014
Unit 11 ~ Learning Guide
Name:________________
INSTRUCTIONS
Complete the following notes and questions as you work through the related lessons.
You are required to have this package completed BEFORE you write your unit test. Do
your best and ask questions about anything that you don't understand BEFORE you
write the unit test.
U11 NOTES: RESPIRATORY SYSTEM (web notes and video)
Respiratory Structures
1. Nasal Cavity
- _________________________
_________________________
_________________________
2. Pharynx
- _________________________
- _________________________
_________________________
3. Glottis
- Top of the _________________
- Upper part of ______________
- Covered by _______________
when swallowing food
4. Larynx
- ____________________, which
contains the vocal cords
- The ----------------------------------5. Vocal Cords
- ______________, as air is forced past, producing sound
6.
Trachea
- ___________________
- Made of rings of ______________ to prevent ______________________
- ____________: move debris laden mucous out of the respiratory system
Page 1 of 17
BCLN BIOLOGY 12 – Rev July 2014
7. Bronchi
- Branches of the
_______________
- One
to
each
_______________
- Bronchus; singular
8. Bronchioles
______________
_____________
of the bronchi
______________
for support
9. Alveoli
- _______________
_______________
of
very
small
bronchioles
- Area where _____
_______________
_______________
10. Pleural Membranes
- ____________________________________________ of the lungs
- ____________________________
- Allows the surface of the lungs to ____________ over the body wall easily
- Seals off ________________________________________
11. Thoracic Cavity
- Chest cavity
- From diaphragm to throat
12. Diaphragm
- Horizontal muscle
- Separates the _______________________________________________
13. Ribs
- Protects _____________________________
- When ribs contact with the intercostal muscles, they rise and increase
___________________________________________________________
Page 2 of 17
BCLN BIOLOGY 12 – Rev July 2014
Air passageways: Filters, Warms, Moistens
Several things happen to the air on its journey into the
alveoli including:
1. Cleansed of debris: This is a two-part process:
a. The
initial
cleaning
is
by
the
_________________________
______________in the nasal passageways.
b. The second is the process that occurs further
along were the accumulation of debris can no
longer get out of through the nose. This is the
role of the mucous lining and the
____________________________________.
Pretty well any material other than the gasses
of the inhaled air will get caught in the
mucous.
The
cilia
are
in
___________________________ beating the
debris-laden mucous upward towards the
________________. When this material is
detected at the back of the mouth, it is
_________________ (or coughed up and spit
out)
2. Adjusted to body temperature:
The more contact the air has with moist tissues that are 37°C, the closer the air
itself gets to 37°C. By the time air gets to the alveoli, there will be no
__________________________________________ than that of the surrounded
tissues.
3. Adjusted to 100% humidity:
The air in the lungs is ____________________________
_____________. One of the things that happens to inhaled air is that it, too,
becomes saturated with water. This is an obvious outcome of having passed
over the mucous lined passageways.
Specializations of Alveoli
1. They are ___________________________________. Up to 300 million alveoli in
the human lung. This provides _______________________________________
____________________________________.
Page 3 of 17
BCLN BIOLOGY 12 – Rev July 2014
2. They are _________________________________. Alveolar walls are only
____________________________. This aids in ______________________.
3. The alveoli have a coating of lipoprotein on their inner surface. This helps to
maintain
surface
tension
thus
preventing
them
from
___________________________________ together during exhalation.
4. They are supplied with __________________________. These are nerve
endings that are ______________________________. During inhalation, these
signal when the alveoli are full enough (stretched). This marks the onset of
______________________.
5. The alveoli surfaces have a very rich blood supply from the pulmonary capillaries
to ensure maximum diffusion. They are highly _________________________.
6. Made up of Squamous (flat) Epithelial cells.
YOU SHOULD WATCH THE SPECIALIZATION OF THE ALVEOLI
VIDEO BEFORE PROCEEDING ANY FURTHER!
3 Things That Make the Lungs Very Efficient at Gas Exchange
1. Huge surface area
2. Only 2 cell layers separate air in lungs from the blood
3. Moist
Processes of the Respiratory System
The Respiratory System supplied the body with oxygen for tis energy production.
Without Oxygen, the body shuts down in minutes. The Respiratory System works
closely with the Circulatory System.
Page 4 of 17
BCLN BIOLOGY 12 – Rev July 2014
Four Processes make up the Respiratory System
1. Breathing
- Inspiration - ________________________________________________
- Expiration - _________________________________________________
2. External Respiration
- ___________________________________________________________
___________________________________________________________
3. Internal Respiration
- ___________________________________________________________
___________________________________________________________
4. Cellular Respiration
- Production of ___________________________________________ within
the cells.
Pleural Membranes
2 sets of membranes:
1. one joined to the lung
2. one joined to the ribs and
diaphragm
The two sets are close together
separated by a slight amount of fluid
(vacuum is created).
If the membranes are punctured, air
enters
the
intrapleural
space,
destroying
the
vacuum.
_______________________________
_________.
They maintain an interpleural pressure
that is less than atmospheric pressure;
keeping the lungs open.
Page 5 of 17
BCLN BIOLOGY 12 – Rev July 2014
Mechanics of Breathing: Inhalation and Exhalation
The chest cavity is dome-shaped. The top and sides are surrounded by the ribs. The
bottom is made up by the diaphragm. It is a ___________________
_______________________.
Inhalation:
1. ___________________________________________________
are
the
PRIMARY STIMULI that cause us to breathe. When Carbon Dioxide and/or
Hydrogen ion concentration gets too high, the Breathing center in the
__________________________ is stimulated.
2. A nerve impulse is sent from the Medulla Oblongata
_____________________________________________________.
to
the
3. The diaphragm contracts and ____________; the rib muscles contract
(intercostal muscles) and raise the ribs. These actions increase the size of the
chest cavity. Increased volume, ________________________________.
4. A partial vacuum is created in the lungs (air pressure in the lungs is reduced).
5. Air Rushes into the lungs from outside in order to rebalance the pressure. This is
the process of inspiration.
**NOTE: Air comes in because the lungs have already opened. The air does not
force the lungs open. This is why it is said that we breathe by
________________________. (Low pressure sucks the air into out lungs)
**NOTE: The lungs themselves have no muscles**
Exhalation:
1. When the lungs are full, stretch receptors in the alveoli are stimulated
2. The Medulla Oblongata is notified and stops sending messages.
3. The diaphragm and rib muscles relax.
4. The chest cavity gets smaller. Decreasing volume, which increases the pressure
in the lungs. _____________________________________________________.
Page 6 of 17
BCLN BIOLOGY 12 – Rev July 2014
Summary of Inhalation and Exhalation
Page 7 of 17
BCLN BIOLOGY 12 – Rev July 2014
In addition to the Respiratory Center in the Medulla Oblongata, there are other
receptors that can respond to stimuli:
a. Carotid bodies - in the ________________________________
b. Aortic bodies - in the _________________
These respond to high concentration of Hydrogen Ions but can also respond to levels of
carbon dioxide in the blood.
Gas Exchange
When _____________________ diffuses from the cells into the blood, only a small
amount of it (9%) reaching the blood is held in simple solution (as dissolved carbon
dioxide).
Another ______ attaches directly to the Hemoglobin to form _________________
________________________.
This remaining 64% combines with water to form ______________________________
and hydrogen ions.
Each time blood passes through the tissues it picks up large quantities of
_________________________________. This then reacts with water to form
Bicarbonate (_______) and Hydrogen Ions (____). There are many substances in the
blood
capable
of
binding
the
excess
free
__________________.
________________________ is one of the most important of these substances. When
Hydrogen (H+) combines with the hemoglobin (Hb), the Hb releases some of the
oxygen attached to it.
YOU SHOULD WATCH THE INHALATION AND EXHALATION
VIDEO BEFORE PROCEEDING ANY FURTHER!
Gas Exchange in Tissues
Internal Respiration
1. 9% of CO2 diffuses into the blood from the cell and travels through the blood as
dissolved CO2.
2. 27%
of
CO2
binds
to
hemoglobin
to
form
carbaminohemoglobin.
3. 64% of CO2 joins with water to temporarily make carbonic acid which breaks
down right away to the ______________________________________________
Page 8 of 17
BCLN BIOLOGY 12 – Rev July 2014
____________________. Carbonic Anhydrase = enzyme that runs this reaction.
4. Most of the released H+ is picked up by the combined form O2 and hemoglobin
__________________________________. The binding of H+ by HbO2 produces
____________________________________________ aids in the release of
oxygen. The H+ concentration and the slight increase in temperature alter the
hemoglobin (protein denatures slightly) and releases oxygen easily.
5. Oxygen then enters the tissue moving from an area of high concentration to
areas of low concentration.
The blood leaving the tissues now contains large quantities of hemoglobin which is free
of oxygen, and is called ____________________________ (HHb). The blood also
contains large amounts of __________________________ (HCO3-). No further
changes
occur
until
the
blood
reaches
the
lungs.
What to know…..
**Be sure you understand all of the equations shown in the diagram to the right. Be able
to name all the molecules and identify the equations as internal respiration.**
Gas Exchange in the Lungs
External Respiration
1. High concentration of Oxygen in lungs. Oxygen diffuses ___________________.
Page 9 of 17
BCLN BIOLOGY 12 – Rev July 2014
2. Oxygen joins with _______________________________ to form Oxyhemoglobin
and Hydrogen ions.
3. H+ picked up by _________________________ to temporarily form carbonic acid
which breaks down right away to produce CO2 + H2O.
4. The dissolved CO2 simply _____________________ into lung alveoli where it is
expelled by normal breathing.
5. The _____________________________________ breaks down to CO2 and a
hemoglobin molecule. The CO2 diffuses into the lungs and is expelled and the
hemoglobin pick up oxygen.
**NOTE: H+ does not accumulate because as soon as it released from HHb, it combines
with HCO3- to release Carbon Dioxide. Hemoglobin is essential in the blood because it
serves as a carrier for ____________________________________________________
____________________ (acts like a buffer).***
___________________________ which allows hemoglobin to grab oxygen easier.
What to know…..
***Be sure you understand all of the equations shown in the diagram above. Be able to
name all the molecules and identify the equations as external respiration. It's easy if you
just reverse the equations from internal respiration.***
YOU SHOULD WATCH THE INTERNAL AND EXTERNAL RESPIRATION
VIDEO BEFORE PROCEEDING ANY FURTHER!
Page 10 of 17
BCLN BIOLOGY 12 – Rev July 2014
U11 PRACTICE: RESPIRATORY SYSTEM
1. Label the respiratory system diagram below and provide a brief description of each
structure's functions. (18 marks)
o
o
o
alveoli
diaphragm
larynx
o
o
o
pleura
pharynx
trachea
o
o
o
bronchial tube
bronchioles
nasal cavity
2. Use a flow chart with arrows to describe the path of air flow from the nose to the
alveoli during inspiration. (7 marks)
Page 11 of 17
BCLN BIOLOGY 12 – Rev July 2014
3. Describe how debris and particulate in air is removed from the lungs. (3 marks)
4. Where is the respiratory center located? (2 marks)
5. What stimuli signal the respiratory center to initiate breathing? (2 marks)
6. What prevents the alveoli from over filling during forced inhalation such as when
exercising? (1 mark)
7. How does oxygen gas move from the alveoli to the blood across the walls of the
alveoli and the capillary? (1 mark)
8. Oxygen is actually transported throughout the blood primarily as a complex within
red blood cells, what is this complex called? (1 mark)
Page 12 of 17
BCLN BIOLOGY 12 – Rev July 2014
9. In what form is carbon dioxide found in plasma? Carbon dioxide reacts with water in
red blood cells to produce what compounds? What enzyme assists in this process?
How does hemoglobin help with carbon dioxide transported by red blood cells? (5
marks)
10. Hemoglobin helps to buffer the blood by binding to excess hydrogen ions. What is
the name of the complex that forms between hydrogen ions and hemoglobin? (1
mark)
11. Give the full name for the following abbreviated compounds related to respiration
and gas exchange. (5 marks)
O2
CO2
Hb
HbO2
HHb
HbCO2
H+
H2CO3
HCO3-
H2O
Page 13 of 17
BCLN BIOLOGY 12 – Rev July 2014
12. List the set of equations that describe external respiration in the alveoli of the
lungs. Remember the alveoli supply oxygen to the blood and receive carbon dioxide
and water from the blood for removal. (4 marks)
13. List the set of equations that describe internal respiration in the capillary bed
between the capillary and the tissue fluid. Remember the tissues receive oxygen
from the blood and dump carbon dioxide and water into the blood (4 marks)
~ END OF BIOLOGY 12 UNIT 11 LEARNING GUIDE ~
Page 14 of 17
BCLN BIOLOGY 12 – Rev July 2014
UNIT 11 ANSWER KEY
U11 PRACTICE: RESPIRATORY SYSTEM
1. Label the respiratory system diagram below and provide a brief description of each structure's
functions. (18 marks)
o
o
o
alveoli
diaphragm
larynx
o
o
o
o
o
o
pleura
pharynx
trachea
bronchial tube
bronchioles
nasal cavity
nasal cavity = warms, moistens and filters air
pharynx = where food and air cross to enter
esophagus and trachea, respectively
larynx = voice box
trachea = carries air from pharynx to bronchi of lungs
Bronchial tubes = branch from trachea into each lung
Pleura – membranes surrounding and protecting lungs
Bronchioles = smaller branches off of bronchial tubes
alveoli = blind air sacs where gas exchange occurs
with capillaries
diaphragm = contracts for inhalation, relaxes for
exhalation
2. Use a flow chart with arrows to describe the path of air flow from the nose to the alveoli during
inspiration. (7 marks)
nose/mouth  pharynx  glottis  trachea  bronchi  bronchioles  alveoli
Page 15 of 17
BCLN BIOLOGY 12 – Rev July 2014
3. Describe how debris and particulate in air is removed from the lungs. (3 marks)
= captured by mucus lining trachea and lungs, then mucus is propelled up to mouth by
cilia, where it is then swallowed or spat out of the body
= sometime coughing is necessary to help move mucus upwards
4. Where is the respiratory center located? (2 marks)
= medulla oblongata of brain
5. What stimuli signal the respiratory center to initiate breathing? (2 marks)
= increased CO2 and H+ concentration stimulate increased breathing rate via the
respiratory center of the medulla oblongata
6. What prevents the alveoli from over filling during forced inhalation such as when exercising? (1
mark)
= alveolar stretch receptors detect inflation of alveoli and send a signal via the
Vagus nerve to the respiratory center of the medulla oblongata that stops the
phrenic nerve and intercostal nerves from stimulating the diaphragm and intercostal
muscles from contracting, resulting in relaxation of these muscles and exhalation
7. How does oxygen gas move from the alveoli to the blood across the walls of the alveoli and the
capillary? (1 mark)
= diffusion
8. Oxygen is actually transported throughout the blood primarily as a complex within red blood cells,
what is this complex called? (1 mark)
= oxyhemoglobin
9. In what form is carbon dioxide found in plasma? Carbon dioxide reacts with water in red blood
cells to produce what compounds? What enzyme assists in this process? How does hemoglobin
help with carbon dioxide transported by red blood cells? (5 marks)
= dissolved CO2 in plasma
= when CO2 reacts with H2O in red blood cells it is converted to bicarbonate ions
(HCO3-) and hydrogen ions (H+)
= carbonic anhydrase
= reacts with CO2 to form carbaminohemoglobin
Page 16 of 17
BCLN BIOLOGY 12 – Rev July 2014
10. Hemoglobin helps to buffer the blood by binding to excess hydrogen ions. What is the name of
the complex that forms between hydrogen ions and hemoglobin? (1 mark)
= reduced hemoglobin
11. Give the full name for the following abbreviated compounds related to respiration and gas
exchange. (5 marks)
O2 = oxygen
CO2 = carbondioxide
Hb = hemoglobin
HbO2 = oxyhemoglobin
HHb
HbCO2 = carbaminohemoglobin
= reduced hemoglobin
H+ = hydrogen ion
H2CO3 = carbonic acid
HCO3- = bicarbonate ion
H2O = water
12. List the set of equations that describe external respiration in the alveoli of the
lungs. Remember the alveoli supply oxygen to the blood and receive carbon
dioxide and water from the blood for removal. (4 marks)
Hb + O2  HbO2
HbCOs  Hb + CO2
HHb  Hb + H+
H+ + HCO3-  H2CO3  H2O + CO2
13. List the set of equations that describe internal respiration in the capillary bed
between the capillary and the tissue fluid. Remember the tissues receive oxygen
from the blood and dump carbon dioxide and water into the blood (4 marks)
HbO2  Hb + O2
H2O + CO2  H2CO3  H+ + HCO3Hb + CO2  HbCOs
Hb + H+  HHb
Page 17 of 17