Veterinary Medical Applications I
Lesson Title: The Respiratory System
TEKS Addressed in Lesson: §130.6. 9A, 9B
(9) The student investigates the body systems and gains a working knowledge of each system's purpose
and functions and how each system is affected by disease. The student is expected to:
(A) Identify the parts of the skeletal, muscular, respiratory, circulatory, excretory, reproductive,
integumentary, immune/lymphatic, digestive, endocrine, and nervous systems;
(B) Describe the functions of the skeletal, muscular, respiratory, circulatory, excretory,
reproductive, integumentary, immune/lymphatic, digestive, endocrine, and nervous systems;
Lesson Objectives: The student will be able to:
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Identify the organs/components of the respiratory system
Describe the function of each component of the respiratory system
List and explain the process of respiration
Explain the relationship between the respiratory system and the cardiovascular system
Determine qualities of a healthy respiratory system
Key Terms/Vocabulary
Alveoli
Bronchi
Bronchioles
Cyanosis
Diaphragm
Epiglottis
Expiration
Inspiration
Larynx
Lower Respiratory
Lungs
Nasal Cavity
Nostrils
Pharynx
Pneumonia
Respiration
Sinuses
Trachea
Upper Respiratory
Interest Approach/Anticipatory Set
Write the components of the respiratory system on index cards. Give each student (or pair of
students) an index card and instruct them to use their device/computer to research this
component.
Have students go around the room and read the information they discovered concerning their
respiratory system component.
Next, students should arrange themselves in the order that air would pass through.
Teaching Plan and Strategy Presentation of New Material
The respiratory system consists of organs that work together to breath. The respiratory system
partners with the circulatory system to bring oxygen into the cells of the body and also to rid the
animal body of waste in the form of carbon dioxide. Oxygen is obtained in the atmosphere and
brought the cells of the body.
Anatomy and Physiology of the Respiratory System
Upper respiratory tract includes nose, mouth, and the beginning of the trachea.
Lower respiratory tract includes the trachea, the bronchi, bronchiole and the lungs where breathing
occurs.
The organs of the lower respiratory tract are located in the chest cavity. They are delineate and
protected by the ribcage, the (sternum), and the muscles between the ribs and the diaphragm.
The trachea – the tube connecting the throat to the bronchi.
The bronchi – the trachea divides into two bronchi. One leads to the left lung, the other to the right
lung. Inside the lungs each of the bronchi divides into smaller bronchi.
The broncheoli - the bronchi branches off into smaller tubes called broncheoli which end in the
pulmonary alveolus.
Pulmonary alveoli – tiny sacs seperated by a single-layer membrane with blood capillaries at the other
end.
The inner surface of the lungs where the exchange of gases takes place is very large, due to the structure
of the air sacs of the alveoli.
The lungs – a pair of organs found in all vertebrates.
The structure of the lungs includes the bronchial tubes air tubes branching off from the bronchi into
smaller and smaller air tubes, each one ending in a pulmonary alveolus.
Mechanics of Breathing
Breathing is the exchange of air between the animal and the environment. This process begins
with inspiration, where the animal takes air into the lungs. Expiration is air being forced out.
The act of breathing has two stages – inhalation and exhalation
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Inhalation – the intake of air into the lungs through expansion of chest volume.
Exhalation – the expulsion of air from the lungs through contraction of chest volume.
Inhalation and exhalation involves muscles:
Rib muscles
Diaphragm muscle
Muscle movement – the diaphragm and rib muscles are constantly contracting and relaxing thus causing
the chest cavity to increase and decrease.
During inhalation – the muscles contract:
Contraction of the diaphragm muscles that causes the diaphragm to flatten, thus enlarging the chest
cavity.
Contraction of the rib muscles that cause the ribs to rise which increases the volume of the chest
allowing air to come in.
The chest cavity expands, reducing air pressure and causing air to be drawn into the lungs. Air passes
from the high pressure outside the lungs to the low pressure inside the lungs.
During exhalation – the muscles relax:
The muscles are no longer contracting, they are relaxed.
The diaphragm curves and rises, the ribs descend – and chest volume decreases.
The chest cavity contracts thus increasing air pressure and causing the air in the lungs to be expelled
through the upper respiratory tract. Exhalation, too, is passive. Air passes from the high pressure in the
lungs to the low pressure in the upper respiratory tract.
Inhalation and exhalation are involuntary and therefore their control requires an effort.
Activity/Application/Student Engagement/Laboratory
 Watch a video simulation of oxygen exchange and explain the role the capillaries play in
this process
 Lung Dissection- Using preserved lungs, have students complete the lung dissection in
order to visualize the structure and the function of all of the lower respiratory system
components
 Use a straw to demonstration lung inflation of the dissection specimen
 Have students draw and label the lung
 Have students label the parts of the upper respiratory system and the lower respiratory
system and describe the function of each component
References/Additional Materials/Extended Learning Opportunities/Enrichment
Intro to Veterinary Science, Thompson
http://www.discoveryeducation.com
http://www.biology.eku.edu/RITCHISO/301notes6.htm
College and Career Readiness Standards:
Science
I. B1. (a-g) Design and conduct scientific investigations in which hypotheses are formulated and
tested.
III. C 1 (a-c) Presentation of scientific/technical information.
V. D 1 (a-g) Understand that scientists categorize things according to similarities and differences.
VI. E 1 (a-f) Know ways in which living things can be classified based on each organism’s internal
and external structure, development, and relatedness of DNA sequences.
© Texas Education Agency 2015