Topic 4.4: Human Physiology and Anatomy 1

Question 1

Identify the structures that comprise the upper and lower respiratory tracts.

Answer 1

The upper respiratory tract consists of the nose and nasal cavities, pharynx, and larynx.

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

Question 2

Discuss the arrangement of the trachea, esophagus, larynx, and epiglottis, which normally prevents food from entering the trachea.

Answer 2

The trachea lies ventral to the esophagus. When food is swallowed, the epiglottis covers the tracheal opening (glottis) so the food slides over the epiglottis and into the esophagus.

Question 3

Summarize the path of an oxygen molecule from the nose to the bloodstream.

Answer 3

O2 travels through the nasal cavity, pharynx, larynx, trachea, brachial tree, and lungs, where it diffuses across the alveolar an capillary endothelial cells to the bloodstream.

Question 4

Describe the function of pulmonary surfactant.

Answer 4

Pulmonary surfactants lower the surface tension of the coating of the alveoli, preventing their sides from collapsing upon themselves.

Question 5

Define respiratory system

Answer 5

Organ system of humans that includes the lungs and associated structures; involved in the exchange of gases; helps control pH.

Question 6

Define ventilation

Answer 6

Process of moving air into and out of the lungs; breathing.

Question 7

Define nose

Answer 7

External structure of the respiratory system that is involved in the process of ventilation.

Question 8

Define pharynx

Answer 8

In vertebrates, common passageway for both food intake and air movement; located between the mouth and the esophagus.

Question 9

Define larynx

Answer 9

Cartilaginous organ located between the pharynx and the trachea; in humans, contains the vocal cords; sometimes called the voice box.

Question 10

Define vocal cord

Answer 10

In humans, fold of tissue within the larynx; creates vocal sounds when it vibrates.

Question 11

Define glottis

Answer 11

Opening for airflow in the larynx.

Question 12

Define epiglottis

Answer 12

Structure that covers the glottis, the air-tract opening, during the process of swallowing.

Question 13

Define trachea

Answer 13

(pl., tracheae) In insects, air tube located between the spiracles and the tracheoles. In tetrapod vertebrates, air tube (windpipe) that runs between the larynx and the bronchi.

Question 14

Define bronchi

Answer 14

(sing., bronchus) In terrestrial vertebrates, branch of the trachea that leads to the lungs.

Question 15

Define bronchiole

Answer 15

In terrestrial vertebrates, small tube that conducts air from a bronchus to the alveoli.

Question 16

Define alveoli

Answer 16

(sing., alveolus) In humans, terminal, microscopic, grapelike air sac found in lungs.

Question 17

Define lung

Answer 17

Internal respiratory organ containing moist surfaces for gas exchange.

Question 18

Define diaphragm

Answer 18

In mammals, dome-shaped muscularized sheet separating the thoracic cavity from the abdominal cavity; contraceptive device that prevents sperm from reaching the egg.

Question 19

Compare and contrast tidal volume, vital capacity, expiratory reserve volume, and residual volume.

Answer 19

Tidal volume is the amount of air that normally moves in and out of the lungs with each breath. Vital capacity is the maximum volumes of air that can be moved in and out during a single breath. Expiratory reserve volume is the air that can be forcibly exhaled beyond the tidal volume. Residual volume is the air left in the lungs after a forced exhalation.

Question 20

Explain why inspiration is considered the active phase of ventilation, and expiration the passive phase.

Answer 20

Inspiration requires the contraction of the diaphragm and external intercostal muscles. Expiration is passive because it requires no muscles contractions, just the elastic recoil of the thoracic wall and lungs.

Question 21

Discuss the roles of the following in controlling respiration: respiratory center, vagus nerve, and carotid bodies.

Answer 21

The respiratory center in the brain automatically sends nerve impulses to the diaphragm and intercostal muscles. The vagus nerve carries inhibitory impulses from the lungs to the brain to stop the lungs from overstretching. The carotid bodies have chemoreceptors that monitor levels of O2 in the blood.

Question 22

Define inspiration

Answer 22

Act of taking air into the lungs; inhalation.

Question 23

Define expiration

Answer 23

Act of expelling air from the lungs; exhalation.

Question 24

Define respiratory center

Answer 24

Group of nerve cells in the medulla oblongata that sends out nerve impulses on a rhythmic basis, resulting in involuntary inspiration on an ongoing basis.

Question 25

Explain the role of hemoglobin in carrying O2, CO2, and hydrogen ions. Which is hemoglobin’s most essential function?

Answer 25

Hemoglobin’s most essential function is to carry O2 (as oxyhemoglobin) to the tissues, but it also carries a small amount of CO2 (as carbaminohemoglobin) back the the lungs. Excess H+ ions can be taken up by hemoglobin, which then becomes reduced hemoglobin.

Question 26

Discuss why arterial blood is bright red in color, but venous blood is a darker blue.

Answer 26

Arterial blood is brighter red than venous blood because the red blood cells in arterial blood contain oxyhemoglobin, which is bright red, compared to the red blood cells in venous blood that contain reduced hemoglobin, which is darker. Blood from a cut appears bright red because hemoglobin becomes oxyhemoglobin upon exposure to O2 in the air.

Question 27

Describe why the process of respiration is said to be a passive process.

Answer 27

The exchange of gases in respiration is by diffusion. No energy is required, which indicates a passive process.

Question 28

Define hemoglobin

Answer 28

Iron-containing respiratory pigment occurring in vertebrate red blood cells and in the blood plasma of some invertebrates.

Question 29

Define external respiration

Answer 29

Exchange of oxygen and carbon dioxide between alveoli of the lungs and blood.

Question 30

Define bicarbonate ions

Answer 30

Ion that participates in buffering the blood, and the form in which carbon dioxide is transported in the bloodstream.

Question 31

Define carbonic anhydrase

Answer 31

Enzyme in red blood cells that speeds the formation of carbonic acid from water and carbon dioxide.

Question 32

Define oxyhemoglobin

Answer 32

Compound formed when oxygen combines with hemoglobin.

Question 33

Define internal respiration

Answer 33

Exchange of oxygen and carbon dioxide between blood and tissue fluid.

Question 34

Define carbaminohemoglobin

Answer 34

Hemoglobin carrying carbon dioxide.

Question 35

Define reduced hemoglobin

Answer 35

Globin chains within the hemoglobin molecule that have combined with hydrogen ions (H+).

Question 36

What is the difference between tonsillitis and laryngitis?

Answer 36

Laryngitis is an inflammation of the larynx, while tonsillitis occurs when the tonsils become inflames and enlarged.

Question 37

Explain how, in addition to the directly harmful effects of cigarette smoke, smoking might predispose the lung to damage by other harmful substances.

Answer 37

Smoking damages the tissues of the respiratory tract directly. Infections from bacteria, fungi, protozoans, and viruses become more likely if the lung tissues is damaged.

Question 38

Which of the diseases of the lungs has a hereditary (genetic) component?

Answer 38

Cystic fibrosis.

Question 39

Define tonsillitis

Answer 39

Inflammation of the tonsils—lymphoid tissue located in the pharynx.

Question 40

Define laryngitis

Answer 40

Inflammation of the larynx, usually resulting in an inability or difficulty in speaking.

Question 41

Define sinusitis

Answer 41

Inflammation of the cranial sinuses in the head.

Question 42

Define otitis media

Answer 42

Inflammation of the middle ear.

Question 43

Define acute bronchitis

Answer 43

Inflammation of the bronchi in the lungs; often caused by a viral or bacterial infection.

Question 44

Define chronic bronchitis

Answer 44

Inflammation of the bronchi in the lungs that is usually caused by smoking or exposure to environmental contaminants.

Question 45

Define asthma

Answer 45

Condition in which bronchioles constrict and cause difficulty in breathing.

Question 46

Define pneumonia

Answer 46

Condition of the respiratory system characterized by the filling of the bronchi and alveoli with fluid; caused by a viral, fungal, or bacterial pathogen.

Question 47

Define pulmonary tuberculosis

Answer 47

Respiratory infection caused by the bacterium Mycobacterium tuberculosis.

Question 48

Define emphysema

Answer 48

Disorder of the respiratory system, specifically the lungs, that is characterized by damage to the alveoli, thus reducing the ability to exchange gases with the external environment.

Question 49

Define cystic fibrosis

Answer 49

Genetic disease caused by a defect in the CFTR gene, which is responsible for the formation of a transmembrane chloride ion transporter; causes the mucus of the body to be viscous.

Question 50

Define pulmonary fibrosis

Answer 50

Respiratory condition characterized by the buildup of connective tissue in the lungs; typically caused by inhalation of coal dust, silica, or asbestos.

Question 51

Define lung cancer

Answer 51

Uncontrolled cell growth that affects any component of the respiratory system.

Question 52

3. The amount of air moved into and out of the lungs during regular breathing is known as the
   a) vital capacity
   b) tidal volume
   c) residual volume
   d) none of the above

Answer 52

b) tidal volume

Question 53

Which of these statements correctly goes with the expiration rather than inspiration?
a) rib cage moves up and out
b) diaphragm relaxes and moves up
c) pressure in lungs decreases, and air comes rushing out
d) diaphragm contracts and lowers

Answer 53

b) diaphragm relaxes and moves up

Question 54

Air enters the human lungs because
a) atmospheric pressure is lower than the pressure inside the lungs
b) atmospheric pressure is greater than the pressure inside the lungs
c) although the pressures are the same inside and outside, the partial pressure of oxygen is lower in the lungs
d) the residual air in the lungs causes the partial pressure of oxygen to be lower than it is outside.

Answer 54

b) atmospheric pressure is greater than the pressure inside the lungs

Question 55

The enzyme carbonic anhydrase
a) causes the blood to be more basic in the tissues
b) forms carbonic acid in the blood
c) actively transports carbon dioxide out of capillaries
d) is active only at high altitudes
e) all of the above

Answer 55

a) causes the blood to be more basic in the tissues

Question 56

Hemoglobin assists in the transport of gases primarily by
a) combining with oxygen
b) combining with CO2
c) combining with H+
d) being present in red blood cells
e) all of the above

Answer 56

a) combining with oxygen

Question 57

The binding of small amounts of carbon dioxide to hemoglobin produces
a) oxyhemoglobin
b) carbonic anhydrase
c) deoxyhemoglobin
d) carbaminohemoglobin
e) bicarbonate hemoglobin

Answer 57

d) carbaminohemoglobin

Question 58

Which of the following is not true of obstructive pulmonary disorders?
a) air does not flow freely in the airways
b) Vital capacity is reduced due to loss of lung elasticity
c) disorders include chronic bronchitis, emphysema, and asthma
d) ventilation takes longer to occur

Answer 58

d) ventilation takes longer to occur

Question 59

Which of the following is not an infection of the upper respiratory tract?
a) tonsillitis
b) sinusitis
c) otitis media
d) bronchitis
e) non of the above

Answer 59

d) bronchitis

Question 60

Smoking is associated with an increased risk of
a) emphysema
b) several types of cancer
c) heart disease
d) all of the above

Answer 60

d) all of the above