respiration

Question 1

what are the components of the upper respiratory tract?

Answer 1

nose, pharynx, and associated structures.

Question 2

what are the components of the lower respiratory tract?

Answer 2

larynx, trachea, bronchi and lungs.

Question 3

what is the most superior part of the respiratory tract?

Answer 3

the nasal cavity.

Question 4

where is the pharynx and what does it do?

Answer 4

part of throat behind mouth and nasal cavity, caries air to larynx.

Question 5

what does the larynx do?

Answer 5

It is involved in breathing and producing sound, protects trachea from food aspiration.
Known as the voice box.

Question 6

Describe the trachea.

Answer 6

Is a cartilagenous tube connecting larynx to the bronchi of the lungs.

Question 7

Describe bronchus/bronchi

Answer 7

conducts air to lungs, no gas exchange at this point.
Branches off at trachea to left and right, becoming narrower in lungs.

Question 8

what is the most important organ in respiratory system

Answer 8

the lungs.

Question 9

where are lungs found in the body ?

Answer 9

near backbone, either side of heart above diaphragm.

Question 10

where is the site of gas exchange in the respiratory system & describe it.

Answer 10

the lungs, extract oxygen from air, transfer to the blood. then carbon dioxide is released from blood to atmosphere.

Question 11

what is the pleurae?

Answer 11

covers the lung, lubricates and reduces friction between lung and chest wall.

Question 12

list the functions of the respiratory system.

Answer 12

1)Provision of O2
2)Elimination of CO2
3)Regulate pH of blood (homeostasis)
4)Phonation (sound production: singing, speaking)
5)Protection against microbes & environmental variations (dehydration, temperature changes)
6)Emotional expression (laughing, crying)
7)Muscles of respiratory system assist in abdominal compression during urination, defecation & childbirth
8)Provide olfactory sensations.

Question 13

name the 5 steps of respiration.

Answer 13

1) ventilation
2) gas exchange
3) gas transport
4) gas exchange
5) cellular respiration.

Question 14

how does air get in and out of lungs ?

Answer 14

air moves bc of pressure differences. high to low

Question 15

what Is Boyles law?

Answer 15

Gas law, states that pressure of a gas is proportional to its volume.

Question 16

what muscles elevate ribs and sternum during inhalation?

Answer 16

external intercostals, pectoralis minor and scalenes ,neck, increase size of thoracic cavity.

Question 17

what muscles depress ribs and sternum during active expiration?

Answer 17

internal intercostals, abdominal muscles decrease size of thoracic cavity.

Question 18

what muscles depress ribs and sternum during passive expiration?

Answer 18

elastic lung recoil, elastic fibres in alveolar wall, surface tension of fluid film lining alveoli.

Question 19

air movement results from different between what?

Answer 19

atmospheric pressure (760mmHg) and alveolar pressure P alv (inside alveolus) decrease = air moves into lungs.

Question 20

what is the pleural cavity?

Answer 20

the space between lung and chest wall.

Question 21

what happens if P ip (inside pleural cavity) is less than P alv?

Answer 21

alveoli expands.

Question 22

what happens if air enters the pleural cavity?

Answer 22

alveoli cannot expand, lungs collapse. called pneumothorax

Question 23

what factors affect rate of pulmonary airflow.

Answer 23

surface tension of alveolar fluid.
lung compliance - capacity for stretching
Airway resistance - controlled by pressures and airflow.

Question 24

what is the role of surfactant in lung ?

Answer 24

decreases surface tension of alveoli to prevent them from collapsing.

Question 25

what is the difference between an immature and mature lung?

Answer 25

immature lung is not conductive to gas exchange. Mature lung has larger surface area.

Question 26

explain lung compliance?

Answer 26

effort is required to stretch lungs and thoracic wall, high compliance = easy expansion.

Question 27

describe airway resistance?

Answer 27

resistance of the respiratory tract to airflow.
Decreases as diameter of airways increases

Question 28

how do air volumes increase?

Answer 28

by inhaling more vigorously and exhaling more completely.

Question 29

Name the 4 pulmonary volumes.

Answer 29

1) Tidal volume - amount of air moved into or out of lungs during a normal inspiration or exhalation (500ml)

2) Inspiratory reserve volume - amount of air that can be inspired forcefully after inspiration of normal tidal volume. (3100ml)

3) Expiratory reserve volume - amount expired forcefully after normal expiration. (1200ml)

4) residual volume - still remaining in respiratory passages and lungs after most forceful expiration (1200ml)

Question 30

how are lung volumes and capacities measured?

Answer 30

spirometry - process of measuring volumes of air that move in and out of respiratory system.
spirometer - device used to measure these pulmonary volumes.

Question 31

Once air enters lungs how does O2 enter bloodstream & CO2 leave?

Answer 31

Gas exchange, = 6 thin layers between alveolus and capillary

Question 32

what are they 6 different layers between alveolus and capillary in gas exchange

Answer 32

1) fluid and surfactant layer
2) alveolar epithelium
3) epithelial basement membrane
4) interstitial space
5) capillary basement membrane
6) capillary endothelium

Question 33

how much hb is in each red blood cell?

Answer 33

280 million