Human Physiology Exam 3: Respiratory System

Front 1

What are four major functions of respiratory system?

Back 1

1.maintenance of normal arterial blood gas:
PaO2 = 98-100mmHg
PaCO2 = 40mmHg
2. removal of metabolic waste
- exhale CO2
3. Phonation - air flow causes vibration of vocal chords
4. Nonrespiratory Functions - defense against inhaled particles, removal of metabolic substances from blood such as, addition of metabolites to arterial blood, trap and dissolve small blood clots

Front 2

What are the general steps of respiration?

Back 2

1. Ventilation - mechanical movement of air between atmosphere and lung alveoli
2. Gas Diffusion - exchange of oxygen and carbon dioxide between the alveolar air and the blood perfusing the lung capillaries
3. transport of blood gases in pulmonary and systemic circulation; diffusion of gases between systemic capillaries and respiring cells
4.cellular respiration - Utilization of oxygen as the final electron acceptor in the production of ATP within the mitochondria

Front 3

What are overall symptoms of pulmonary disease?

Back 3

Decrease in PaO2 - hypoxia
Increase in PaCO2 - hpercarbia
respiratory acidosis - ECF becomes acidic

Front 4

What is respiratory acidosis?

Back 4

Decreased ability to expire CO2

Front 5

What determines O2 delivery to cells?

Back 5

Pa O2, Hgb.O2 and O2 diffusion
Cardiac output and blood flow

Front 6

What happens at the end of a normal relaxed exhale?

Back 6

Opposing elastic forces of chest wall expansion cause longs to recoil and creates a negative subatmospheric pressure of -4mmHg

Front 7

Where is conducting zone of respiratory system? What is the function of this area?

Back 7

Mouth/nose -> end of terminal bronchioles

air flow, phonation, warm, saturation with water, traps foreign particles

Front 8

What is respiratory zone and the function of it?

Back 8

respiratory bronchi alveolar ducts and alveoli, gas exchange by diffusion

Front 9

What is function of smooth muscle in respiratory system and where is it?

Back 9

It lines airways from trachea to respiratory bronchi. Contraction or relaxation changes radius of airways therefore airway resistance

Front 10

What causes airway constriction?

Back 10

Parasympathetic, Eicosanoids, Histamine

Front 11

What causes airway dilation?

Back 11

Sympathetic, eicosanoids, transpulmonary pressure

Front 12

What does caritlage do in respiratory system?

Back 12

Trachea and bronchi have cartilage to maintain cylindrical structure

Front 13

What is the function of cilia?

Back 13

They are found on epithelial surfaces of airways down to end of respiratory bronchi, constantly beat directionally toward trachea

Front 14

What do glandular cells do?

Back 14

They line the epithelium and secrete mucus

Front 15

What do epithelial cells do?

Back 15

secrete watery substance that that allows the mucus to freely floa

Front 16

What causes cystic fibrosis?

Back 16

A genetic defect in chloride channels to secrete watery fluid that allows mucous to freely float

Front 17

What do macrophages and IgA do?

Back 17

Provide defense against inhaled foreign substances

Front 18

What are pneumocytes?

Back 18

Alveolar cells

Front 19

What are Type 1 pneumocytes?

Back 19

elongated, cover large surface are

Front 20

What are Type 2 pneumocytes?

Back 20

round, most numerous, produce surfactant, regenerative capacity to become Type 1 or Type 2 pneumocyte

Front 21

What is surfactant?

Back 21

Mixture of phospholipid and protein that form a monolayer between interface of air and water in alveoli. It lowers surface tension of air water interface and increase compliance of lung. Work of breathing reduced when surfactant present.

Front 22

When is surfactant produced during fetus?

Back 22

Late third triemester.

Front 23

What happens if baby is born before surfactant produced?

Back 23

Respiratory Distress Syndrome

Front 24

What is atmosphere pressure?

Back 24

Pressure surrounding body, mouth and nose

Front 25

What is alveolar pressure?

Back 25

Pressure of air in alveolus

Front 26

What is intrapleural pressure?

Back 26

ALSO called intrathoracic pressure, Pip

Front 27

What is transpulmonary pressure?

Back 27

Pressure that acts to expand lungs. Palv - Pip. This ability depends on compliance of lungs

Front 28

How can we calculate Lung compliance?

Back 28

Compliance lung = Change in Volume / change in Transpulmonary Pressure

Front 29

What determines lung compliance?

Back 29

Elastic connective tissue properties of lung and surface tension at air water interface

Front 30

What is pressure that determines movement of air in and out of lungs?

Back 30

Patm - Palv

Front 31

What is Boyle's Law?

Back 31

The pressure of a fixed amount of gas is inversely related to the volume of the container

Front 32

What is volume of conducting zone?

Back 32

150mL

Front 33

What is in daily inhaler for people with asthma?

Back 33

Corticosteroid to reduce inflammation

Front 34

What is in rescue inhaler for people with asthma?

Back 34

SNS mimetics. Beta 2 agonist

Front 35

What helps stimulate surfactant?

Back 35

lymphatic vessels

Front 36

What is the formula for pressure to keep lungs from collapsing?

Back 36

P = 2T/r
T is tension and r is radius

Front 37

How is diaphragm innervated for ventilation?

Back 37

the diaphragm is innervated by alpha motor neurons arising from Cervical Spinal Cord segments. The major contribution of innervation comes from C4. Contraction of diaphragm causes change in volume of thorax.

Front 38

What happens after diaphragm innervated and thorax expands in ventilation for inspiration?

Back 38

Decrease in Pip and Palv -> increase in Ptp -> lungs expand

Front 39

What are accessory muscles of inspiration?

Back 39

External intercostal muscles and anterior neck msucles

Front 40

What are accessory muscles of expiration?

Back 40

Internal intercostal muscles and abdominal muscles

Front 41

What happens during exhalation?

Back 41

At resting, Palv>Patm; no motor command no AP required; Diaphragm relaxes -> decreases volume of thorax -> Pip returns to normal -> Ptp decreases -> lungs recoil

Front 42

What is total lung capacity proportional to? What is it in males and females?

Back 42

Body size, 6000mL males and 4200 mL females

Front 43

What is residual volume ? What is the volume for males and females

Back 43

Volume of air trapped in lungs and can't exhale with increasing age: .9-1.4 L males and .8 - 1.2 L for females

Front 44

What is vital capacity for females and males?

Back 44

4-5 L males and 3-4 L for females

Front 45

What does Total Lung Capacity include?

Back 45

includes residual volume or volume of air that is trapped in lungs and cannot be exhaled

Front 46

What is vital capacity?

Back 46

It is the air that can move in and out of lungs so Total Lung Capacity - Residual Volume

Front 47

What is Tidal Volume?

Back 47

Amount of air we normally breathe in and out on average ~ 500mL but proportional to body size

Front 48

When will tidal volume increase?

Back 48

When exerting energy

Front 49

_______ + __________ = vital capacity

Back 49

Expiratory and Inspiratory tidal volumes

Front 50

What is forced vital capacity?

Back 50

rate at which you can force/exhale vital capacity

Front 51

What is FEV1?

Back 51

Forced expiratory volume in one second , volume of vital capacity that can be exhaled in one second

Front 52

What does how fast one can force the vital capcity out indicate?

Back 52

resistance to air flow

Front 53

What will doctors look at for patients with lung disease?

Back 53

FEV1/FVC

Front 54

What is minute ventilation?

Back 54

In one minute, how much more in or out = volume/time
Vmin = Tidal volume * Respiratory Rate

Front 55

What is alveolar ventilation?

Back 55

Of air we move in or out, how much gets to alveoli for gas diffusion

Front 56

What is dead space volume?

Back 56

Amount of air trapped in conducting zone about 150 mL

Front 57

How do we calculate Alveolar ventilation or Valv?

Back 57

(TV - dead space conducting zone) * RR

Front 58

How do you calculate maximum voluntary ventilation?

Back 58

As subject to take max deep breaths as fast as they can for fifteen seconds. and multiply that times four to get per minute.

Front 59

What does average person without obstructive lung disease have for percentage of FEV1/FVC?

Back 59

ABOUT 80%

Front 60

What do you see with someone who has obstructive lung disease ?

Back 60

Decrease total vital capacity, Decreased FEV1, and decreased FEV1/FVC

Front 61

What do you see in someone with restrictive lung disease ?

Back 61

Decreased total vital capacity, decreased FEV1, but somewhat normal FEV1/FVC