Respiratory

Question 1

What are the functions of the respiratory system (6)?

Answer 1

• Provide oxygen to and remove carbon dioxide from the tissues
• Voice production via vocal chords in the larynx, vibrations of the vocal folds
• Thermoregulation
• Panting - breaths out hot air, breaths in cold air
• Counter current heat exchange to conserve heat
• Olfaction (smell)

Question 2

Name the structures in the upper respiratory tract (8)

Answer 2

• Nares,
• nasal cavity
• oral cavity,
• sinuses,
• Nasopharynx
• oropharynx
• pharynx,
• larynx

Question 3

Name the structures in the lower respiratory tract (7)

Answer 3

• Trachea
• Bronchi
• bronchioles
• Lungs
• bronchioles,
• alveolar ducts,
• alveoli

Question 4

Where are the nares located?

Answer 4

Extends from nares to pharynx.

Question 5

What are the two sides of the nares separated by?

Answer 5

Spetum (cartilage)

Question 6

What is the floor of the nares?

Answer 6

The hard palate

Question 7

What lines the nares?

Answer 7

Respiratory mucosa and olfactory mucosa (caudally).

Question 8

What type of epithelium is respiratory epithelium?

Answer 8

ciliated columnar epithelium

Question 9

What is the purpose of the respiratory muscosa (4)?

Answer 9

• Warms/moistens air,
• traps foreign particles,
• goblet cells produce mucus,
• olfaction

Question 10

What are the turbinates?

Answer 10

Bone and cartilage fold in the nares.

Question 11

“What is the function of the turbinates (3)?

Answer 11

• Warming air
• Humidifying air
• Removing foreign particles

Question 12

What are the sinuses, how many are there, and what do they contain?

Answer 12

Hollow spaces in the skull that make the head lighter, there are four, and they contain cells that produce mucus that drains into the nasal cavity.

Question 13

What is the hard palate and where is it found?

Answer 13

It is the roof of the mouth, made of bone.

Question 14

What is the soft palate and where is it found?

Answer 14

Soft muscular tissue at the back of the mouth that
extends from the hard palate.
The flexible division between the oropharynx and nasopharynx.
Brachycephalic dogs often have excessively long soft palate

Question 15

What is the pharynx, how many sections are there, what are their names?

Answer 15

It is the throat and there are three sections. Nasopharynx, oropharynx, laryngopharynx.

Question 16

Where is the nasopharynx positioned?

Answer 16

Between the nasal cavity and the oesophagus, above the soft palate.

Question 17

Where is the oropharynx positioned?

Answer 17

Between oral cavity and the laryngopharynx. Below soft palate.

Question 18

Where is the Laryngopharynx positioned?

Answer 18

Space in front of the larynx. Behind soft palate, in front of larynx

Question 19

What is the philtrum?

Answer 19

The philtrum is the cleft that divides the two halves of the upper lip. Philtrum is deeper in carnivores.

Question 20

What are the alar folds?

Answer 20

Winged folds in the nares.

Question 21

What is the trachea, what is it made out of, and what lines it?

Answer 21

The trachea is more commonly known as the windpipe.
It is made out of C-shaped cartilage with the opening facing dorsally. Trachealis muscle (fibrous muscle) closes the gap in the C.
It is lined with Pseudostratified columnar epithelium embedded with cilia and goblet cells that secrete mucus. Cilia aids in removing mucus and dust/debris.

Question 22

What is the carina?

Answer 22

It is where the trachea divides into the two main bronchi.

Question 23

What are the primary bronchi?

Answer 23

The left and right tracts that lead toward the lung after the carina.

Question 24

What do primary bronchi divide into?

Answer 24

Lobar bronchi

Question 25

What do lobar bronchi divide into?

Answer 25

Smaller branches of bronchioles.

Question 26

Where to the bronchioles lead?

Answer 26

To the alveoli ducts, they terminate at the site of alveoli.

Question 27

What are alveoli?

Answer 27

They are lung lobes that are surrounded by a dense set of capillaries that allow gas exchange via passive diffusion.

Question 28

What is the pleura, and what are its two parts?

Answer 28

The pleura is the membrane surrounding the lungs. There is the parietal pleura, which is the outer wall. And the visceral layer, which is against the organ (lung).

Question 29

What is the pleura cavity and what does is contain?

Answer 29

It is the space between the parietal and visceral pleura that allows room for the lungs to expand while taking in air. It contains a small amount of serous fluid for lubrication.

Question 30

Describe the passage of air from the nares to the alveoli.

Answer 30

Air is brought in through that nares, it is warmed and filtered in the turbinates, it comes into the pharynx, first the nasopharynx, then the laryngopharynx. Through the epiglottis and the glottis, into the trachea, down to the carina and into the left and right primary bronchi, into the lobar bronchus, then into the bronchiole, then the alveoli where passive gas exchange takes place.

Question 31

What is the epiglottis?

Answer 31

The epiglottis is the part of the laryngeal

cartilage that covers the glottis during the act of swallowing.

Question 32

What are the two stages of ventilation, and what happens physiologically?

Answer 32

Inspiration/Inhalation

Diaphragm + Intercostal muscles contract > increases volume of thorax
Decreases pressure within the thorax
Draws air into lungs

Expiration/Exhalation

Largely passive process - does not require energy e.g. muscle contraction like inhalation does
As intercostal muscles/diaphragm relax, the volume of the thorax decreases > the pressure in the thorax increases
Expels air from lungs

Question 33

Difference between oxyhaemoglobin and deoxyhaemoglobin?

Answer 33

Oxyhaemoglobin is oxygenated red blood cells.

Deoxyhaemoglobin is deoxygenated red blood cells.

Question 34

How does oxygen and carbon dioxide move via passive diffusion?

Answer 34

Oxygen moves from the lumen of the alveoli (high concentration) into the erythrocytes within the capillary blood (low concentration)

Co2 moves in the opposite direction - concentration in the blood is higher than the alveoli therefore it moves out of the blood into the alveoli to be exhaled.