Respiratory System (BS 1)

Question 1

Describe the upper respiratory tract.

Answer 1

The upper respiratory tract includes the nose and pharynx.

Question 2

Describe the location and structure of the lungs.

Answer 2

The lung has 3 lobes:

• The superior lobe
• The middle lobe
• The inferior lobe

The lungs are located in the chest (the thoracic cavity) and rest on the diaphragm muscle.

Question 3

13.4 Describe the neural control of breathing and the role of chemoreceptors.
!!!!!

Question 4

Describe the lower respiratory tract.

Answer 4

The lower respiratory tract consists of the trachea, bronchial tree, and lungs.

Question 5

Describe the role of the nose.

Answer 5

Nose: Cleans air before it goes on and moistens and warms the air. Breathing starts here, mucus lining and tiny hairs (cilia) inside help prevent foreign objects to enter and to trap large air impurities before being drawn further into the respiration system

Question 6

Describe the role of the mouth.

Answer 6

Mouth: Like the nose it has many functions it’s starting point of the digestive system as well as a secondary inhaler and exhaler.

Question 7

Describe the role of the pharynx,

Answer 7

A chamber behind the nose and mouth that leads to the trachea. Is shared with the digestive system, food goes on down the esophagus and air passes on through the trachea but never both at the same time.

Question 8

Describe the role of the larynx.

Answer 8

Also known as the voice box. It is made up of two folds of tissue. When we exhale the two folds vibrate and make sounds.
1. passageway for air.
2. 2. A valve to close off the air passage from the digestive one (epiglottis),
3. 3. is a voice box.

Question 9

Describe the role of the trachea.

Answer 9

A pipe that carries the air to the lungs. Has glands that produce mucous to trap particles (dirt) from the air. Armed tube allows air to pass beyond the larynx to where it divides into the left and right bronchi. Provides protection to the digestive system’s esophagus right behind it.

Question 10

Describe the role of the bronchi.

Answer 10

There are two. (bronchus is plural) Each leading to the lungs. The tubes that go from trachea one goes into each lung. Glands = mucous = clean.

Question 11

Describe the role of the alveoli.

Answer 11

Gas exchange happens here with capillaries oxygen and carbon dioxide. Look like tiny balloons or grapes on a stalk. The air sacs are the last stage. Air cells or sacs are leaves of our respiratory tree. Gas exchange happens here I’ll trade you fresh oxygen for tour used carbon dioxide.

Question 12

What 2 other, non-respiratory functions do the lungs carry out?

Answer 12

• Expulsion of foreign bodies
• Defence against infection

Question 13

Describe the function of the pulmonary vessels.

Answer 13

Pulmonary arteries carry deoxygenated blood from the right ventricle to the lungs’ alveoli.

Pulmonary veins carry oxygenated blood from the alveoli to the left atrium.

Question 14

Define spirometry

Answer 14

It’s a method for studying pulmonary ventilation.

Question 15

Define tidal volume (TV)

Answer 15

The volume of air inspired or expired with each normal breath (500ml)

Question 16

Explain how inspiration happens.

Answer 16

• The external intercostal muscles contract, while the internal intercostal muscles relax.
• The ribs are pulled upwards and outwards, increasing the volume of the thorax (upper part of the body).
• The diaphragm muscles contract, causing them to flatten, which also increases the volume of the thorax.
• The increased volume of the thorax results in the reduction of pressure in the lungs.

-Atmospheric pressure is now greater than pulmonary pressure (lung pressure), forcing air into the lungs.

Question 17

Explain how expiration happens.

Answer 17

• The internal intercostal muscles contract, while the external intercostal muscles relax.
• The ribs move downwards and inwards, decreasing the volume of the thorax.
• The diaphragm muscles relax and are pushed up again by the contents of the abdomen that were compressed during inspiration. The volume of the thorax is, therefore, further decreased.
• The increased volume of the thorax increases the pressure in the lungs.
• This increased pressure means that external air pressure is lower than the pulmonary pressure, forcing air out of the lungs.

Question 18

What is the diaphragm?

Answer 18

A sheet of muscle that separates the thorax from the abdomen.

Question 19

What are the intercostal muscles?

Answer 19

These are the muscles between the ribs that allow for the expansion/compression of the thoracic cavity.

Question 20

What is the explanation for the oxygen dissociation curve?

(Shortern answer)

Answer 20

• The shape of the haemoglobin molecule makes it difficult for the first oxygen molecule to bind to one of the sites on its four polypeptide subunits because they are closely united. Therefore at low oxygen concentrations, little oxygen binds to haemoglobin. The gradient of the curve is shallow initially.
• However, the binding of this first oxygen molecule changes the quaternary structure of the haemoglobin molecule, causing it to change shape. This change makes it easier for the other subunits to bind to an oxygen molecule. In other words, the binding of the first oxygen molecule induces the other subunits to bind to an oxygen molecule.
• It therefore takes a smaller increase in the partial pressure of oxygen to bind the second oxygen molecule than it did to bind the first one. This is known as positive cooperativity because binding of the first molecule makes binding of the second easier and so on. The gradient of the curve steepens.
• The situation changes, however, after the binding of the third molecule. While in theory it is easier for haemoglobin to bind the fourth oxygen molecule, in practice it is harder. This is simply due to probability. With the majority of the binding sites occupied, it is less likely that a single oxygen molecule will find an empty site to bind to. The gradient of the curve reduces and the graph flattens off.

Question 21

Explain the term respiratory acidosis.

Answer 21

A condition that occurs when your lungs can’t remove all of the carbon dioxide produced by your body

Question 22

Explain the term respiratory alkalosis.

Answer 22

A condition marked by a low level of carbon dioxide in the blood due to breathing excessively.

Question 23

Describe the lower respiratory tract.

Answer 23

The windpipe (trachea) and within the lungs, the bronchi, bronchioles, and alveoli. Deep in the lungs, each bronchus divides into secondary and tertiary bronchi, which continue to branch to smaller airways called the bronchioles.

Question 24

Describe the branching of the bronchial tree.

Answer 24

Trachea > Main Bronchi > Lobar bronchi > Segmental bronchi > bronchioles > Terminal bronchioles.

Question 25

Describe the role of the bronchioles.

Answer 25

Divides and subdivides into smaller and smaller branches, like tree branches that get smaller as they grow up and out. By the time the air has reached here from outside, it has been warmed up to body temperature, filtered, and moisturized.

Question 26

Describe the upper respiratory tract

Answer 26

The nose or nostrils, nasal cavity, mouth, throat (pharynx), and voice box (larynx)