Respiration 1

Question 1

Explain the steps in external respiration

Answer 1

1. Ventilation or gas exchange between the atmosphere and air sacs (alveoli) in the lungs.
2. Exchange of O2 and CO2 between air in alveoli and the blood in the pulmonary capillaries
3. Transport of O2 and CO2 by the blood between lungs and tissue
4. Exchange O2 and CO2 between the blood in the systemic capillaries and the tissue cells

Question 2

forces in the chest

Answer 2

• Intrapleural fluid cohesiveness (stickiness)
• Transmural pressure gradient x2
  [Atmospheric (760) - Intrapleaural (756)]

Question 3

What is the average resting PO2 at systematic capillaries?

Answer 3

40 mm Hg (partially saturated hemoglobin)

Question 4

Normal PO2 at pulmonary capillaries?

Answer 4

100 mm Hg (fully saturated hemoglobin)

Question 5

The % hemoglobin saturation depends on the;

Answer 5

PO2 of the blood

Question 6

Why Respiration?

Answer 6

• Oxidative phosphorylation for ATP

- To maintain viability

Question 7

Respiratory surface area ________ with size

Answer 7

increases

Question 8

General function of respiration

Answer 8

to obtain O2 for use by the body’s cells and to eliminate the CO2 the body cells produce

Question 9

2 separate but related processes

Answer 9

Internal respiration

External respiration

Question 10

Internal Respiration

Answer 10

[Cellular respiration]
- metabolic processes carried out within the mitochondria, which use O2 and produce CO2, while deriving energy from nutrient molecules.

Question 11

Respiratory quotient (RQ)

Answer 11

The ratio of CO2 produced to O2 consumed
(in internal resp)
Varies depending on the foodstuff consumed
Brain, heart, muscle

Question 12

External Respiration

Answer 12

Refers to the sequence of events involved in the exchange of O2 and CO2 between the external environment and the cells of the body

Question 13

4 steps of external respiration

Answer 13

> Ventilation – movement of air into and out of the
lungs
O2 and CO2 are exchanged between air in alveoli
and blood within the pulmonary capillaries by
means of diffusion
Blood transports O2 and CO2 between lungs and
tissues
O2 and CO2 are exchanged between tissues and
blood by process of diffusion across systemic
(tissue) capillaries

Question 14

Non-respiratory Functions of Respiratory System

Answer 14

• Route for water loss and heat elimination
• Enhances venous return
• Helps maintain normal acid-base balance
• Enables speech, singing, and other vocalizations
• Defends against inhaled foreign matter
• Removes, modifies, activates, or inactivates various
  materials passing through the pulmonary circulation
• Nose serves as the organ of smell

Question 15

Answer 15

Pseudostratified columnar ciliated epithelium, trachea

Question 16

Answer 16

Simple squamous epithelium (Mesothelium and Endothelium)

Question 17

Simple squamous epithelium

Mesothelium and Endothelium

Answer 17

lining of body cavities
(mesothelium visceral and parietal)
Function: passive transport

Question 18

Respiratory Airways

Answer 18

Tubes that carry air between the atmosphere and the air sacs

Question 19

Respiratory Airways

Answer 19

• Nasal passages (nose)
• Pharynx (common passageway for respiratory and
  digestive systems)
• Trachea (windpipe)
• Larynx (voice box)
• Right and left bronchi
• Bronchioles
  Alveoli (air sacs) are clustered at ends of
  terminal bronchioles

Question 20

GAs transfer occurs across the:

Answer 20

respiratory epithelium

Question 21

Trachea and larger bronchi

Answer 21

Fairly rigid, non-muscular tubes

Rings of cartilage prevent collapse

Question 22

Bronchioles

Answer 22

• No cartilage to hold them open
• Walls contain smooth muscle innervated by
  autonomic nervous system
• Sensitive to certain hormones and local chemicals

Question 23

Thin-walled inflatable sacs

Answer 23

Alveoli

Question 24

Function in gas exchange

Answer 24

alveoli

Question 25

Alveoli cell walls consist of:

Answer 25

single layer of flattened Type I alveolar cells

Question 26

encircle each alveolus

Answer 26

Pulmonary capillaries

Question 27

Type II alveolar cells

Answer 27

secrete pulmonary surfactant

Question 28

guard lumen

Answer 28

Alveolar macrophages

Question 29

permit airflow between adjacent alveoli (collateral ventilation)

Answer 29

Pores of Kohn

Question 30

Pulmonary artery

Answer 30

deoxygenated blood

Question 31

pulmonary vein

Answer 31

oxygenated blood

Question 32

Relationship of Resistance and Flow to Vessel Radius

Answer 32

Flow proportional to differential pressure and r4

Question 33

Pressure gradient of blood flow

Answer 33

is pressure difference between beginning and end of a vessel

Question 34

Blood flows from area of ________ pressure to area of ________ pressure

Answer 34

higher | lower

Question 35

Resistance is:

Answer 35

a measure of the opposition of blood flow through a vessel

Question 36

Resistance of blood flow depends on:

Answer 36

Blood viscosity Vessel length Vessel radius

Question 37

Major determinant of resistance to flow is

Answer 37

vessel’s radius Slight change in radius produces significant change in blood flow R is proportional to 1/r4

Question 38

Respiration:

Answer 38

for ATP’s sake to maintain cellular viability and function

Question 39

Order of respiration

Answer 39

Air --> lungs --> capillaries --> tissue

Question 40

diffusion in alveoli

Answer 40

500nm

Question 41

How does the respiratory system contribute to homeostasis

Answer 41

- By obtaining O2 from and eliminating CO2 to the external environment. - Helps regulate the pH of the internal environment by adjusting the rate of removal of acid forming CO2

Question 42

Why is homeostasis of respiration necassary?

Answer 42

- Cells need a constant supply of O2 delivered to them to support their energy-generating chemical reactions. - These reactions generate CO2 that must be continuously removed. - Furthermore, this CO2 generates carbonic acid with which the body must deal with to maintain the proper pH of the internal environment > Cells can only survive within a narrow pH.