1. The Respiratory System
UEQ: How do we exchange oxygen to and carbon dioxide from the human body?

2. What is the respiratory system?
The system that
brings oxygen into the body and expels carbon dioxide out of the body.
ensures that during inspiration, or inhalation, air is brought from the atmosphere to the lungs by a series of cavities, tubes and openings.
ensures that during expiration, or exhalation, air is pushed out of the lungs into the atmosphere using the same structures.

3. THINK ABOUT IT: WHAT ORGANS ARE APART OF THE UPPER RESPIRATORY TRACT?
Major Organs
Accessory Organs
Nose
Oral cavity , or mouth
Nasal cavities
Paranasal sinuses
Pharynx, or throat

4. The Upper Respiratory Tract

5. The nose Bone and cartilage support the nose internally
Two nostrils or nares
Air enters and leaves through here
Internal hairs guard nostrils
Prevents larger particles carried in air

6. The nasal cavities Hollow space behind the nose
Divided into narrow canals separated from each other by cartilage and bone – nasal septum.
Nasal conchae
bones and bony processes that divide the cavity into passageways
Support the mucous membrane
Increases surface area
Pseudostratified ciliated columnar epithelium
Secretes mucous from goblet cells
Water evaporates from this lining moistening the air
Mucus traps debris coming in with the air
Lined with blood vessels
As air enters, heat from blood transfers to air and warms it
Adjusts air temp to body temp

7. Paranasal sinuses
Air filled spaces within the frontal, ethmoid, sphenoid and maxillary bones of the skull and opening into the nasal cavity.
Lined with mucous membranes – continuous with the lining of the nasal cavity
Reduce the weight of the skull
Resonance chambers that affect quality of voice

8. Pharynx, or Throat
Funnel shaped passage way that connects the nasal and oral cavities to the larynx
Passage way for food moving to esophagus, and air moving to the larynx
Helps to produce sound of speech
Has three parts:
Nasopharynx: where the nasal cavities open above the soft palate
Oropharynx: where the oral cavity opens
Laryngopharynx: area that opens up into the larynx

9. Pathway of air through the upper respiratory system.
REMEMBER!!!! Each time that you take a breath, there are three very important things that happen.
1. The air that you breathe in is cleaned by tiny hairs in your nose, trapping little bits of dirt and dust and germs that come in through your nose.
2. As you breathe, the air is made slightly wet. Your nose having damp passages does this.
3. The next thing that takes place when air enters your nose is that the air is warmed. This happens because the blood flows through the lining of the nose and gives off heat.

10. Snot and more.. Protecting us from harm
"Snot", is just another word for mucus. When bits of stuff get stuck in your nose hairs, it’s the mucus or snot that surrounds the stuff and traps it.
Boogers:
Boogers are dried-up snot and dirty nose debris.
Encrusted mucus is filled with the junk that’s in the air you breathe - dust, pollen, germs, sand, fungi, smoke, small particles from outer space.

11. And now for the mucus model…
Achoo…
What you'll need:
Boiling water (be careful with this)
A cup
Gelatin
Corn syrup
A teaspoon
A fork
Instructions:
Fill half a cup with boiling water.
Add three teaspoons of gelatin to the boiling water.
Let it soften before stirring with a fork.
Add a quarter of a cup of corn syrup.
Stir the mixture again with your fork and look at the long strands of gunk that have formed.
As the mixture cools slowly add more water, small amounts at a time.

12. Mucus model? – How does it compare to the real thing?
Model made up of gelatin (protein) and corn syrup (sugar)
Mucus is made mostly of sugars and protein.
The long, fine strings you could see inside your fake snot when you moved it around are protein strands.
These protein strands make snot sticky and capable of stretching

13. CHECK IT!
Complete the questions for a stamp.. 

14. THINK ABOUT IT: WHAT ORGANS ARE APART OF THE LOWER RESPIRATORY TRACT?
Major Organs
Accessory Organs
Larynx, or voicebox
Glottis
Trachea, or windpipe
epiglottis
The bronchial tree
Diaphragm
The lungs

15. The Lower Respiratory System

16. Larynx, or voicebox
Cartilaginous structure that serves as a passageway for air between the pharynx and trachea.
A triangular box
top of the triangle is located to the front of the neck (Adam’s apple)
Framework of muscles and cartilage
Thyroid cartilage
Cricoid cartilage
Epiglottic cartilage
Houses the vocal cords
Allows for air in and out of the trachea
Prevents foreign objects entering into trachea

17. Vocal Cords Vocal folds False vocal cords True vocal cords
Composed of muscle tissue and connective tissue
Covered with mucous membrane
False vocal cords
Upper folds
Do not produce sound
Muscle fibers help close airway when swallowing
True vocal cords
Muscle tissue and elastic fibers
Forced air between TVC causes them to vibrate and produce sound
Words = changing shapes of pharynx, oral cavity; and use of the tongue
Pitch= contracting or relaxing muscles that alter tension

18. Glottis Opening between vocal cords
Durning normal breathing, relaxed vocal cords, the glottis opens
During swallowing/ eating, muscles around the false vocal cords contract, the glottis closes.

19. Epiglottis A flap of soft tissue above the vocal cords
The larnyx will move upward against the epiglottis when swallowing to prevent food, water and saliva from entering the lungs.

20. The trachea, or windpipe
A tube that connects the larynx to the primary bronchi
Walls consist of connective tissue and smooth muscle
Reinforced by c-shaped cartilaginous rings
Prevents the trachea from collapsing
Lies anterior to the esophagus
Soft tissue that completes the c-rings, allow for esophagus to expand as food moves through
The outermost layer of the mucous membrane that lines the trachea is pseudostratified columnar epithelium with goblet cells.
Traps particles and moves it upwards to pharynx to be swallowed

21. The Bronchial Tree
Tubes that allow air to pass through, and are reinforced with cartilaginous rings, like the trachea.
Divided into the left and right primary bronchi, which lead into the lungs
Divison is located in the mediastinum, approximately at the level of the 5th thoracic vertebrae
Branch into the secondary bronchi
tertiary bronchi
keep dividing until they are about 1 mm in diameter
Bronchi that are 1 mm in diameter are called bronchioles
Terminal bronchioles
Respiratory bronchioles
Alveolar ducts
Alveolar sacs
Alveoli

22. The Lungs Paired, cone-shaped organs
Separated by the mediastinum
Diaphragm and rib cage enclose them
Suspended by the bronchus and major blood vessels
Visceral pleura surrounds each lung
Continues to the parietal pleura which attaches and surounds the throacic cavity
Potential space between the pleura = pleural cavity
Filled with serous fluid
Reduces friciton of lungs moving against the thoracic cavity during breathing
Right lung has three lobes, the left lung only two – due to the heart pointing towards the left
Broken even further into lobules, which house bronchioles serving the alveoli

23. The Alveoli Lungs have about 300 million alveoli
Each alveoli sac is surrounded by blood capillaries
Made up of simple squamous epithelium
This is the site where gas exchange happens

24. Be sure to complete the following
Your check it questions
The diagram at the back of the packet

25. WARM UP!
Why is it important for the capillaries from the cardiovascular system to be numerous and surround the alveoli?
When finished with the question, take a moment and breathe – notice what happens. Write it down.

26. Cardio/ Respiratory connection
Oxygen diffuses from alveolar walls and enters the blood.(where it can now go to other cells in the body)
Carbon Dioxide diffuses from the blood through the walls and enters the alveoli. (where it can be exhaled and released)

27. Alveoli Exchange of Gases:
Using the picture below EXPLAIN the gas exchange process:

28. Why do the blood cells start blue and then turn red?

29. CHECK IT!

30. Breathing, or ventilation
Has two phases
Inspiration – moving air into the lungs
Expiration –moving air out of the lungs

31. Inspiration Active phase of ventilation
In this phase the diaphragm and muscles of the ribcage contract – diaphragm moves downward and looks flattened
The volume of the thoracic cavity will increase, so does the lung volume
The pressure within the alveoli is less than the pressure outside in the atmosphere. There is a difference in pressure (or pressure gradient) and air will move into the body naturally.

32. Pressure and volume have an inverse relationship
Pressure inside the lungs and alveoli decrease, atmospheric pressure will push outside air into airways
During this time the pressure in the alveoli drops 2mmHg below atmospheric pressure
In response, atmospheric pressure forces air into the airways
The external intercostal muscles between ribs are stimulated and move the ribs and sternum upwards
Enlarges thoracic cavity even further
Internal pressure is further reduced; increases amount of air into the lungs

33. Water within the serous fluid found in between the visceral and parietal pleura creates an attraction between the pleura, and the membranes move upward during inspiration
This expands the lung in all directions.
Too much water in the alveolar sacs creates a surface tension that may collapse the alveoli.
Certain cells within the alveoli secrete a surfactant – lipids and proteins
Fills the alveolar air spaces – reducing the tendency to collaspe, especially when lung volumes are low
Makes it easier to inflate alveoli

34. Expiration Passive phase of ventilation
Come from elastic recoil and surface tension
No effort is required for air to leave the body
Diaphragm and muscles of the ribcage relax – diaphragm looks cone shaped
Pressure within the alveoli increases to about 1mmHg above atmospheric pressure
Forces the air out of the lungs
The volume of the thoracic cavity will decrease, so does the lung volume

35. Maximum inspiration and forced expiration
Involves muscles of the back, chest, and neck
Thoracic cavity increases more than normal, for maximum lung capacity
Usually during exercise
Contraction of the ribcage muscles forces the ribcage to move downward and inward
Involves the abdominal muscles pushing against the abdominal organs which pushes against the diaphragm, pushing more out of the lungs
Usually during exercise, singing, playing an instrument, or blowing out a candle

36. CHECK IT!
And then the activity.

37. Volumes of Air in the Lungs
Warm UP: Are our lungs ever void of air? Why or why not?

38. Volumes of air within the lungs during ventilation
Why do we need to know this?
Knowing the amounts of air in the lungs and how it flows through the respiratory system helps to diagnose respiratory issues

39. Respiratory Air Volumes and Capacities
Spirometry is the test that measures air volumes in or out of the lungs.
Three distinct repiratory volumes can be measured:
Resting Tidal volume
Inspiratory reserve volume
Expiratory reserve volume
One inspiration + one expiration = respiratory cycle.
Air that enters of leaves during a respiratory cycle is the tidal volume

40. Respiratory cycle: One inspiration plus one expiriation
Respiratory cycle: One inspiration plus one expiriation. (Breathe in- breathe out)
Resting Tidal volume- the normal amount of air that enters the lungs and leaves the lungs during a respiratory cycle.
The average is about 500 milliliters of air per breath in and the same amount out.

41. During Tidal volume you do not use the total amount of space in your lungs! They only use about 75-80%

42. Inspiratory Reserve Volume: When you take a deep breath in to hold more air than a usual breath. “Forced inhalation”.
Expiratory Reserve Volume: Forced expiration. Expelling air beyond the tidal volume. Even after the most forceful exhale however you still have air left in your lungs.
This left over air is called the Residual Volume.

43. 4. 2. 1. 5. 3. 6.

44. Vital Capacity: Combining the tidal volume with both the inspiratory reserve volume and the expiratory reserve volume.
Total Lung Capacity: The vital capacity plus the residual volume. All the possible air that can come into or out of the lungs, including the air that never leaves the lungs.

46. Fill in the following table with the appropriate terms:

47. Respiratory centers and control of breathing…
Medullary respiratory center- controls both inspiration and expiration
Found within the pons and medulla oblongata
Medulla oblongata has two groups
Ventral respiratory group – controls basic rhythm
Dorsal respiratory group- controls the diaphragm

48. Factors that Affect breathing flow charts.. CHECK IT!PP
Create flow charts for the following factors that affect breathing
CO2 levels
O2 levels
Depth of breathing
Emotional upset
Holding your breath
Hyperventilation

49. How and why Gas Exchange happens:
Location: The alveoli
Method: Diffusion

50. Partial pressure: In a mixture of gases such as air or blood, each gas accounts for a portion of the total pressure the mixture produces. The amount of pressure each gas contributes is the partial pressure.

51. Diffusion of Gases:
When blood reaches the alveolus / lungs the blood is oxygen poor- it has depleted its oxygen source to the rest of the body and needs to “pick up more”.

52. Diffusion of Gases:
Due to the pressure gradient, oxygen will move from the alveoli to the blood stream.
In other words, there is more oxygen in the alveoli than the bloodstream, so oxygen will naturally move into the bloodstream.

53. So what about Carbon Dioxide?
Carbon dioxide will be or
in the bloodstream.
higher
lower
Carbon dioxide will or
the bloodstream into the alveoli where it will be expelled out of the body.
move into
out of

54. Color and label the diagram

55. GAS TRANSPORT

56. Factors affecting release of O2
Increase in CO2 concentration= increase in O2 release
If blood
Becomes acidic
Temperate increases
More O2 is released to skeletal muscle during physical activity; less O2 released to non active cells
HYPOXIA – deficiency of O2 reaching tissues

57. GAS TRANSPORT - OXYGEN
OXYHEMOGLOBIN
HEMOGLOBIN
PO2is high – oxygen dissolves in blood and combines with hemoglobin to form oxyhemoglobin
Unstable bonding
As PO2 decreases in the body, O2 is released from oxyhemoglobin
O2 diffues across the membrane of cells to be used in cellular respiration
98% of oxygen in blood binds to hemoglobin
a protein in red blood cells that carries oxygen

59. CO2 Transport
Capillary blood gains CO2, as tissues have increased levels of PCO2
Transported in three ways to the lungs:
Dissolved in plasma
Bound to hemoglobin
Bicarbonate ions
Amount of CO2 dissolved in plasma dependent on its partial pressure
Increased PCO2 = more CO2 in solution
Only 7% of CO2 transports in this form

60. GAS TRANSPORT CO2 loosely bonds with hemoglobin = carbaminohemoglobin
Bicarbonate Ions
CO2 loosely bonds with hemoglobin = carbaminohemoglobin
Decomposes readily in regions of low PCO2 – releasing CO2
Only about 23% of the CO2 carried in the blood is formed in molecule, as this reaction happens slowly
Most important CO2 transport mechanism
CO2+ H2O => H2CO3 (carbonic acid)
Occurs slowly in plasma
Carbonic anhydrase speeds up reaction, releasing H+ and HCO3- (bicarbonate ions)
Bicarbonate ions diffuse into the plasma – 70% of all CO2 in blood is transported this way

61. CO2 Transport Continued
Plasma release CO2
Dissolved CO2 diffuses into the alveoli (alveoli PCO2 is low
Bicarbonate Ions Release CO2
As blood passes through the capillaries of the lungs
At same time H+ and HCO3- combine to make H2CO3 under influence of carbonic anhydrase
H2CO3 breaks down quickly to form CO2 and H2O
CO2 then diffuses into the alveolus

62. CO2 Transport Continued
Carbaminohemoglobin release of CO2
As blood passes through the capillaries of the lungs
Release of CO2 happens
Will continue until PCO2 of blood and alveolar air are at equilibrium