UNIT 11: Respiratory

Question 1

What is respiration?

Answer 1

The process by which animals take in oxygen necessary for cellular metabolism and release carbon dioxide that accumulates in their bodies as a result of the expenditure of energy

Question 2

How does gas transfer occur?

Answer 2

through passive diffusion

Question 3

What does the respiratory system consist of?

Answer 3

nasal cavity, pharynx, trachea, bronchi and lungs

Question 4

Where the pharynx and larynx lead to?

Answer 4

they lead to the lungs. The larynx is connected to thee trachea which will branch into the right and left bronchi

Question 5

What do the bronchi divide into?

Answer 5

the bronchioles

Question 6

Where do the terminal bronchioles lead air to?

Answer 6

they lead air to the respiratory bronchioles

Question 7

Where do the respiratory bronchioles lead to?

Answer 7

they connect to a fan of alveolar ducts and sacs

Question 8

What is the function of the alveolar ducts and sacs?

Answer 8

to moisten and cleanse the air that is taken in and transfer it to the gas-exchangeing portion of the lung.

Question 9

What is found inside these ducts and sacs?

Answer 9

capillaries (contain connective tissue fibers)

Question 10

What are some important factors of gas exchange?

Answer 10

the relationship between oxygen pressure in the alveoli, the thickness of the alveolar and endothelial cells

Question 11

What are the two types of alveolar cells?

Answer 11

Type I and Type II

Question 12

What is Type I

Answer 12

responsible for gas exchange

Question 13

What is Type II

Answer 13

responsible for the secretion of pulmonary surfactant and the re-absorption of sodium around water

Question 14

What are the two zones that air passages are divided into?

Answer 14

the respiratory and conducting zone

Question 15

What is the respiratory zone?

Answer 15

where gas exchange occurs and it includes bronchioles and alveoli

Question 16

What is the conducting zone?

Answer 16

all the structures through which air passes before reaching the respiratory zone

Question 17

Where are the lungs suspended?

Answer 17

within the pleural cavity

Question 18

What can be known as the thoracic cage?

Answer 18

the ribs and diaphragm

Question 19

What does the thoracic cage consist of?

Answer 19

mainly the lungs, but between the lungs and the thoracic wall there is a low volume of pleural space that is sealed and fluid filled

Question 20

What controls the contractions of muscles while breathing?

Answer 20

the respiratory center within the medulla oblongata

Question 21

What happens during inhalation?

Answer 21

volume of thorax increases due to the lowering of the diaphragm. the ribs are also raised and moved outward by the contraction of the external intercostal muscles

Question 22

What does the increase in thoracic volume do?

Answer 22

it reduces alveolar pressure and air is drawn into the lungs

Question 23

What happens during exhalation

Answer 23

the diaphragm and external intercostal muscles relax and reduce the thoracic volume

Question 24

What does reducing the thoracic volume do?

Answer 24

raises alveolar pressure and forces air out of the lungs

Question 25

What is a surfactant?

Answer 25

found in alveoli and they reduce surface tension

Question 26

Where are pulmonary surfactants produced?

Answer 26

in type II alveolar cells

Question 27

What is the purpose of pulmonary surfactants?

Answer 27

helps reduce the effort of breathing and help prevents the collapse of alveoli

Question 28

How do surfactants reduce the chances of alveolar collapse?

Answer 28

by stabilizing surface tension when the alveolar sac is expanded

Question 29

When does collapse occur?

Answer 29

when the pressure inside a small alveolar sac is greater than the pressure of the larger alveolar sac which will then force the air from the small sac to the large sac.

Question 30

How is oxygen transported in blood?

Answer 30

hemoglobin

Question 31

What is hemoglobin?

Answer 31

principle part of a red blood cell, a large protein with 4 polypeptide chains and 4 iron-containing heme groups

Question 32

Where does oxygen attach itself to in the hemoglobin?

Answer 32

to the iron atoms on the heme groups

Question 33

What conditions effect oxygens ability to bind to the iron group?

Answer 33

pressure of oxygen in surrounding area, pH, and carbon dioxide levels

Question 34

When does hemoglobins affinity for oxygen decrease?

Answer 34

if temperature increases, pH decreases, or carbon dioxide levels increase

Question 35

What happens in a decrease in pH?

Answer 35

it will reduce Hb/O2 affinity since the shape of the oxygen binding sites of the hemoglobin molecule change

Question 36

What happens when there is a ride in body temperature?

Answer 36

Hb/O2 affinity will be reduces (increased energy will prevent bonds from forming or break any bonds that are currently in place)

Question 37

How does an increased CO2 content affect the affinity?

Answer 37

because the CO2 will be binding where O2 should be binding

Question 38

What are the three main ways that CO2 is transported in the blood?

Answer 38

dissolved into molecular CO2 (small %), reacting with NH2 groups of hemoglobin and other proteins to form carbamino compounds (larger amounts), and transported as bicarbonate (Main method)

Question 39

What is one way pH is regulated?

Answer 39

through breathing (pH decreases- respiration rate and depth increases)

Question 40

What is breathing?

Answer 40

automatic and rhythmic behaviour regulated by several nerve centers in the brain (pons and medulla oblongata)

Question 41

What helps ventilate the lungs?

Answer 41

the muscles and diaphragm

Question 42

What drives inspiration?

Answer 42

the activity of the inspiratory neuron's in the dorsal inspiratory group drive (this gets interrupted by inhibition from the pneumotaxic centre)

Question 43

What is the pneumotaxic centre?

Answer 43

this allows exhalation and then allows the cycle of inspiration too occur again

Question 44

What network of neurons allow breathing to be regulated?

Answer 44

higher brain center's, chemoreceptors, and mechanoreceptors

Question 45

What happens when PCO2 levels are increased?

Answer 45

level of pH in CSF decreases (body. has the ability to adjust breathing patterns to the environment)

Question 46

What is PCO2?

Answer 46

the main drive for increased breathing rates since the chemoreceptors are more sensitive to high PCO2 than low O2

Question 47

What is the Hering-Breuer reflex?

Answer 47

when the body is maintaining normal ventilation and refers to prevent over-inflation of the lungs. This reflex is stimulated by pulmonary stretch receptors (prevents over-extension of the lungs)

Question 48

What is hypoxia?

Answer 48

when animals use anaerobic pathways, or adjust respiratory and cardiovascular systems in order to deliver oxygen throughout there body while there is reduced O2 availability