Chapter 6- The Respiratory System

Question 1

hypoxia

Answer 1

deficiency in amount of oxygen reaching the tissues due to low oxygen concentration in blood.

Question 2

location of lungs

Answer 2

thorasic cavity, structure specially designed to perform breathing.

Question 3

vibrissae

Answer 3

nasal hairs

Question 4

nasal hairs

Answer 4

vibrissae

Question 5

pharynx

Answer 5

behind nasal cavity at back of mouth. common pathway for both air and food

Question 6

larynx

Answer 6

below pharynx. only pathway for air. contains two vocal cords

Question 7

epiglottis

Answer 7

opening of larynx (glottis) is covered by this to keep food away from this pathway.

Question 8

where does air go after larynx?

Answer 8

passes into cartilaginous trachea and into one of two mainstream bronchi (both contain ciliated epithelial cells to catch material that has made it past the mucous membranes in the nose and mouth)

Question 9

anatomy of lungs

Answer 9

bronchi divide into smaller bronchioles which divide into small balloon-like structures at the end where gas exchange occurs called alveoli. each alveolus is coated with surfactant (detergent that lowers surface tension and prevents the alveolus to carry O and CO2)

Question 10

why is left lung smaller than right?

Answer 10

heart is near the left lung

Question 11

pleurae, visceral pleura, and parietal pleura

Answer 11

surround each lung and form a closed sac against which the lung expands. visceral (directly touches lung during expansion), parietal (outer layer touching chest wall). space in between the two is called intrapleural space which has a thin layer of fluid

Question 12

Diaphragm

Answer 12

Skeletal muscle that generates negative pressure to allow lung expansion. divides thoracic cavity from abdominal cavity. under somatic control, even tho breathing is under autonomic control. contracts during inhalation and relaxes during exhalation.

Question 13

what drives air into the lungs?

Answer 13

pressure differentials between lungs and intrapleural space

Question 14

inhalation

Answer 14

active process using both diaphragm and external intercostal muscles (one layer of muscles between the ribs) to expand thoracic cavity. deep breath in = more volume so less intrapleural pressure

Question 15

negative-pressure breathing

Answer 15

pressure inside lungs decreases due to increased volume so its pressure is less than the environment which means that the air will be sucked into the lower pressure lungs.

Question 16

exhalation

Answer 16

not an active process. relaxation of external intercostal muscles. chest cavity decreases in volume so pressure is increased and air goes out to lower pressure air.

Question 17

spirometer

Answer 17

assess lung capacities and volumes

Question 18

total lung capacity (TLC)

Answer 18

maximum volume of air in the lungs when one inhales completely. 6-7 liters

Question 19

residual volume (RV)

Answer 19

minimum volume of air in lungs when one exhales completely.

Question 20

vital capacity (VC)

Answer 20

difference between minimum and maximum volume of air in the lungs (TLC-RV)

Question 21

tidal volume (TV)

Answer 21

volume of air inhaled or exhaled in a normal breath

Question 22

expiratory reserve volume (ERV)

Answer 22

volume of additional air that can be forcibly exhaled after a normal exhalation

Question 23

inspiratory reserve volume (IRV)

Answer 23

volume of additional air that can be forcibly inhaled after a normal inhalation

Question 24

ventilation center

Answer 24

located in the medulla oblongata. regulates breathing. neurons here contain chemoreceptors that are CO2 sensitive. as CO2 in blood increases then repiratory rate will increase so CO2 levels will fall with increased exhalation.

Question 25

hypercarbia/ hypercapnia

Answer 25

CO2 level in blood rising

Question 26

what surround the alveolus?

Answer 26

a network of capillaries which bring deoxygenated blood from the pulmonary arteries

Question 27

pulmonary arteries

Answer 27

originate from the right ventricle of the heart then oxygenated blood returns to the left atrium of the heart via pulmonary veins.

Question 28

pulmonary capillaries

Answer 28

O2 in alveoli flows down its partial pressure gradient from alveoli into these. O2 will bind to hemoglobin for transport here.

Question 29

vascularization

Answer 29

developing more blood vessels

Question 30

thermoregulation and the respiratory system

Answer 30

vasodilation and vasoconstriction. due to large surface area over which alveoli and capillaries interact.

Question 31

lines of defense for lungs

Answer 31

1. nasal cavity with small hairs to trap particulate matter
2. nasal cavity contains enzyme: lysozyme- attacks peptidoglycan walls of gram-positive bacteria
3. internal airways lined up with mucus/ mucociliary escalator (mucous catches germs then it will either be spit out or swallowed)
4. alveoli contain immune cells (macrophages)
5. mast cells in lungs- performed antibodies release imflammatory chemicals to promote an immune response. (can be cause of some allergies)

Question 32

bicarbonate buffer system

Answer 32

in blood. body wants to maintain pH between 7.35 and 7.45. lower pH= acidemia (result is to increase respiratory rate), higher ph= alkalemia (result is to decrease respiratory rate)

Question 33

bicarbonate buffer system equation

Answer 33

(more basic) CO2 +H2O H2CO3 H+ + HCO3- (more acidic)