Name: ______Date: ______
Unit L Notes #3 - Gas Exchange
- When carbon dioxide ______, only a small amount of it (9%) reaching the blood is held in simple solution. (this
portion is carried as______)
- Another ______% attaches directly to the ______to form
______(______).
- The______, the remaining _____%, combines with ______to form
______(HCO3-) and ______(H+).
- Each time blood passes through the tissues; it picks up large quantities of carbon dioxide. This then reacts with water to form Bicarbonate (______) and Hydrogen Ions (____).
Ex. ______+ ______à ______à ______+ ______
* The reaction above takes place ______with the help
of an ______called “ ______”- This reaction can be reversed by the same enzyme as blood enters the pulmonary capillaries of the lungs.
- There are many substances in the blood capable of binding to the excess free
hydrogen ions ______. ______
is one of the most important of these substances. When ______(H+) combines with the ______(____), the ______
______. The Hb binds with the H+ to make (______) or “ ______”
A) Gas Exchange in Tissues : ______
1.CO2 diffuses into the blood from the cells.
2.CO2 joins with water to make Bicarbonate and Hydrogen Ions thanks to
______
CO2 + ______à ______+ ______
3. Most of the ______is picked up by the combined form of O2 and
hemoglobin (______). The taking up of H+ by HbO2
(produces HHb), causing the ______to release its oxygen easily.
- The H+ concentration (______near tissue) and the slight ______
______alters the hemoglobin structure (Slight______)
causing it to ______easily.
4.______moving from an area of high concentration to an area of low concentration.
- The blood leaving the tissues now contains large quantities of hemoglobin, which is
free of oxygen but carrying ______, at this point these Hb’s are called
______(______) The blood also contains large amounts of
______(______). No further changes occur until the blood reaches the lungs.
B) Gas Exchange in the Lungs – ______
* The environment near the lungs is different than near the tissues, the capillaries near the lungs are at a ______temperature and at a ______
1.High concentration of Oxygen in lungs. ______
______.
2.The reduced hemoglobin (HHb)______causing it to lose its H+ to become ______(Hb). This Deoxyhemoglobin readily picks up oxygen to form Oxyhemoglobin (HbO2)
Ex. ______à ______+ ______à _____+ ______à ______
3.H+ picked up by Bicarbonate to produce CO2 + H2O
Ex. ______+ ______à ______à ______+ ______
4.The ______where it is expelled by normal breathing.
***NOTE: H+ does not accumulate because as soon as it is released from HHB, it combines with HCO3- to release Carbon dioxide.
- Hemoglobin is essential in the blood because it ______
______
______
The Respiratory System : Review #2
Respiratory System : (Learning Outcomes L5 – L8)
L.O. L – 5 Lungs, Pleural Membranes, Ribs, and Diaphragm
___ 1. What makes up the floor of the chest cavity?
___ 2. What chemicals are primarily responsible for stimulating us to breathe?
___ 3. What is the normal shape of the diaphragm?
___ 4. What happens to the diaphragm when it contracts?
___ 5. What happens to the ribs when the intercostal muscles contract?
___ 6. When the ribs and diaphragm contract, what happens to the overall volume of the
thoracic cavity?
___ 7. What happens to the air pressure within the lungs when a vacuum is produced??.
L.O. L – 6 Nervous System Control
___ 1. The levels of what two substances are the main stimuli for the chemoreceptors in the base of the brain to send an impulse to stimulate us to inhale?
___ 2. These substances stimulate what part of the brain?
OVER à
___ 3. Some receptors are able to detect low oxygen concentration. Give two locations
for these chemoreceptors.
___ 4. Where are the stretch receptors located that detect that the lungs have expanded?
___ 5. What happens when these receptors send their message to the Medulla notifying
it that that the lungs are full?
____ 6. Name the nerve that the nerve impulse travels on its way from the stretch
receptors to the Medulla.
L.O. L – 7 Internal and External Respiration
___ 1. During internal respiration as CO2 diffuses into the blood, some of it directly
joins with what molecule, and what is the new combined molecule called?
____2. What happens to the majority of the CO2 that leaves the tissue? (p. 290)
___ 3. Name the enzyme that speeds up the above reaction, and where are these
enzymes located?
___ 4. The hydrogen ions [H+] that are produced during this reaction are taken up by
what molecule, and what is the name of this new combined form of the molecule?
___ 5. During EXTERNAL respiration, oxygen from where to where?
___ 6. What must happen to carbaminohemoglobin (HbCO2) and reduced hemoglobin
(HHb) in order for them to form deoxyhemoglobin (Hb)?
____7. When oxygen binds onto Deoxyhemoglobin, what name is given to this new form
Of Hemoglonin (Hb) and give its short-hand version or symbol?
___ 8. The Hydrogen Ions are picked up by Bicarbonate to undergo a reaction to
produce what two molecules?
___ 9. What happens to the CO2 that is produced?
___ 10. List three roles that Hemoglobin plays in the blood in the blood?
___ 11. Give the chemical formula for the Bicarbonate Ion.
L.O. L – 8 Oxyhemoglobin, Carbaminohemoglobin, and Bicarbonate Ions
___ 1. List three ways that carbon dioxide can be transported by the blood. Give the
percentage that is carried in each method?
___ 2. Carbon Dioxide is mainly carried in the form of what Ion?
___ 3. Give the name for a combination of hemoglobin carrying oxygen.
___ 4. Where is the partial pressure of Oxygen the greatest: in tissues or in the lung
alveoli?
___ 5. What happens to the amount of oxygen held by hemoglobin when the partial
pressure of oxygen decreases?
___ 6. Where is the partial pressure of oxygen least: in tissues or in lung alveoli?
___ 7. What effect does a slightly lower temperature have on the amount of oxygen
carried by hemoglobin?
___ 8. Where in the circulatory system is the temperature lowest?
____9. What happens to Oxyemoglobin when the temperature rises at the internal
tissues?