1. No category

Cohen: Memmler’s The Human Body in Health and Disease
Phases of Respiration
Respiration:
• Process of obtaining oxygen from environment and
delivering it to cells
Phases of Respiration
Chapter 18:
The Respiratory
System
1. Pulmonary ventilation – between air and lungs
2. External gas exchange – between lungs and blood
3. Gas transport in the blood – carries oxygen and CO2
4. Internal gas exchange – between blood and tissue cells
Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins
Cohen: Memmler’s The Human Body in Health and Disease
Figure 18-1 Overview of respiration.
From which side of the heart
does blood leave to travel
to the lungs?
To which side does it return?
Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins
Cohen: Memmler’s The Human Body in Health and Disease
Structures of the Respiratory System
The Nasal Cavities – open spaces between roof of
mouth and cranium
Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins
Cohen: Memmler’s The Human Body in Health and Disease
Figure 18-2 The respiratory system.
What organ is located in the medial depression of the left lung?
Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins
Cohen: Memmler’s The Human Body in Health and Disease
Structures of the Respiratory System
The Pharynx – the throat; carries air to lungs and
food to stomach
• Nostrils (nares) – air enters here
– Nasopharynx - Superior portion near nose
• Nasal septum –partition that divides nostrils
– Oropharynx - Middle portion near mouth
• Conchae – shell-like projections inside cavity
– Laryngeal pharynx - Inferior portion near larynx
• Air is Filtered, Warmed, Moistened by mucus
membranes
Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins
Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins
1
Cohen: Memmler’s The Human Body in Health and Disease
Structures of the Respiratory System
Cohen: Memmler’s The Human Body in Health and Disease
Figure 18-3 The larynx.
The Larynx
• Cartilage framework between pharynx and trachea;
(Adam’s apple)
– Epiglottis – flap that closes over esophagus
– Vocal cords – used for speech as air flows over them
– Glottis – opening in the vocal cords
Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins
Cohen: Memmler’s The Human Body in Health and Disease
Structures of the Respiratory System
Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins
Cohen: Memmler’s The Human Body in Health and Disease
Structures of the Respiratory System
The Trachea
The Lungs
• Takes air to lungs; horseshoe-shaped rings of cartilage
to keep shape
Located on either side of mediastinum
The Bronchi
• Two primary branches that enter the lungs from the
trachea
• Right lung – divided into three lobes that match bronchi
• Left lung – divided into two lobes that match bronchi
– Bronchial tree branches of the bronchi into the lungs
– Bronchioles – smaller, narrower branches
– Terminal bronchioles – end of the branches
• Alveoli – air sacs at the end of bronchioles
– Thin walls – one cell thick to allow gases to pass
– Surface area 60 square meters (volleyball court)
Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins
Cohen: Memmler’s The Human Body in Health and Disease
Structures of the Respiratory System
Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins
Cohen: Memmler’s The Human Body in Health and Disease
The Process of Respiration
The Pleurae
Pulmonary Ventilation
• Diaphragm – muscle that sits below lungs
• Inhalation (inspiration) is active phase in which the
diaphragm and chest muscles contract
• Parietal pleura - connective tissue coverings of the
lungs
– Surfactant – substance to reduce the surface tension
of fluids in lungs; allows lungs to expand
• Exhalation (expiration) is passive phase; muscles relax
Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins
Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins
2
Cohen: Memmler’s The Human Body in Health and Disease
Figure 18-6 Pulmonary ventilation.
Cohen: Memmler’s The Human Body in Health and Disease
The Process of Respiration
Pulmonary Ventilation
• Lung volumes
– Tidal volume – regular relaxed breathing
– Residual volume – volume of air left in lungs
– Inspiratory reserve volume – breathing in beyond
normal breath
– Expiratory reserve volume – breathing out beyond
normal breath
– Vital capacity– volume breathed out after deep
breath
What muscles are located
between the ribs?
Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins
Cohen: Memmler’s The Human Body in Health and Disease
Figure 18-8 A spirogram.
– Functional residual capacity- volume left after normal
breath
– Total capacity- total volume of air in lungs
Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins
Cohen: Memmler’s The Human Body in Health and Disease
The Process of Respiration
Gas Exchange
• External exchange— between alveoli and capillaries
– Oxygen leaves alveoli and enters capillaries
– Carbon dioxide leaves capillaries and enters alveoli
• Internal exchange— between body tissue and capillaries
– Oxygen leaves capillaries and enters tissue
– Carbon dioxide leaves tissue and enters capillaries
What lung volume cannot be measured with a spirometer?
Which lung capacities cannot be measured with a spirometer?
Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins
Cohen: Memmler’s The Human Body in Health and Disease
Figure 18-9 Gas exchange.
Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins
Cohen: Memmler’s The Human Body in Health and Disease
Process of Respiration
Transport of Oxygen
• Most oxygen is transported in blood by hemoglobin.
Transport of Carbon Dioxide
• 10% is dissolved in plasma and fluid in red blood cells
• 15% is combined with protein of hemoglobin and
plasma proteins
• 75% dissolves in blood fluids and is converted to
bicarbonate ion
Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins
Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins
3
Cohen: Memmler’s The Human Body in Health and Disease
Figure 18-10 Regulation
of respiration.
Nervous Control –
your brain is in control
Cohen: Memmler’s The Human Body in Health and Disease
Regulation of Respiration
Chemical Control
• Central chemoreceptors
• Control center is
located in medulla and
pons of brain stem
– Located near medulla
• Fibers extend from the
spinal cord, through
phrenic nerve to
diaphragm and chest
muscles
• Peripheral chemoreceptors
Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins
Cohen: Memmler’s The Human Body in Health and Disease
Regulation of Respiration
– Respond to raised CO2 level (hypercapnia)
– Located in neck and aortic arch
– Respond to oxygen level considerably below normal
• Other factors such as pain or emotional responses can
affect breathing patterns
Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins
Cohen: Memmler’s The Human Body in Health and Disease
Regulation of Respiration
Abnormal Ventilation
Breathing Patterns
• Hyperventilation
Measured in breaths per minute
– High oxygen level and low CO2 level (hypocapnia)
• Adults: 12 to 20 bpm
– Increases blood pH
• Children: 20 to 40
• Hypoventilation
• Infants: more than 40
– Insufficient air in alveoli
– Decreases blood pH
Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins
Cohen: Memmler’s The Human Body in Health and Disease
Regulation of Respiration
Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins
Cohen: Memmler’s The Human Body in Health and Disease
Regulation of Respiration
Some Terms for Altered Breathing
Results of Inadequate Breathing
• Hyperpnea- increase in depth and rate
• Cyanosis – bluish color due to insufficient O2
• Hypopnea- decrease in depth and rate
• Hypoxia – lower than normal oxygen in tissues
• Tachypnea- excessive rate, as in exercise
• Hypoxemia – lower than normal oxygen in blood
• Apnea – temporary cessation for short periods
• Suffocation- cessation of breathing due to some
blockage
Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins
Copyright © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins
4