Loading presentation...

Present Remotely

Send the link below via email or IM

Copy

Present to your audience

Start remote presentation

  • Invited audience members will follow you as you navigate and present
  • People invited to a presentation do not need a Prezi account
  • This link expires 10 minutes after you close the presentation
  • A maximum of 30 users can follow your presentation
  • Learn more about this feature in our knowledge base article

Do you really want to delete this prezi?

Neither you, nor the coeditors you shared it with will be able to recover it again.

DeleteCancel

Make your likes visible on Facebook?

Connect your Facebook account to Prezi and let your likes appear on your timeline.
You can change this under Settings & Account at any time.

No, thanks

Respiratory and Circulatory Systems

KIN 416 - Berry College - Dept. of Kinesiology
by

David Elmer

on 8 September 2016

Comments (0)

Please log in to add your comment.

Report abuse

Transcript of Respiratory and Circulatory Systems

Respiratory System
(pulmonary respiration)
1. Ventilation
2. Diffusion
O tension
2
CO tension
2
# of branches
"alveoli"
Parietal pleura
Visceral pleura
Diaphragm
Conducting zone
Respiratory zone
no gas exchange
filters and humidifies air
air always warm/wet when it reaches alveoli
prevents lung tissue from drying out
site of gas exchange
300 million alveoli
surface area of a tennis court, 1 cell thick
coated in to lower surface tension and prevent alveolar collapse
surfactant
Mechanics of breathing
Inspiration
1. diaphragm contracts
forces abdomen downward and forward
lifts ribs outward
2. Intrapleural pressure reduced
causes lungs to expand
3. Intrapulmonary pressure reduced
pressure drops below atmospheric
air flows into lungs
result of bulk flow
Expiration
During exercise, accessory muscles are involved as well
1. Chest and lungs passively return to resting position
elastic effect - no muscular effort necessary
During exercise, abdominal muscles contract as well
(unless exercising - active)
2. diaphragm pushed up
ribs pulled downward
3. Intrapulmonary pressure increased
air forced out of lungs
Pulmonary ventilation
movement of gas in and out of the lungs
total amount of gas ventilated = amount of gas per breath X # of breaths
not all gas participates in exchange
anatomical dead space
alveolar ventilation
gas that reaches respiratory zone
gas that's not used
V
V
.
=
V
T
x
f
A
V
D
+
.
.
measured with a
spirometer
0.5 L
3.0 L
1.2 L
1.3 L
2.5 L
6.0 L
3.5 L
4.7 L
COPD -
chronic obstructive pulmonary disease
impaired vital capacity and forced expiratory volume
Airway Resistance
amount of pressure difference for breathing depends on the resistance of the airways
Airflow =
P - P
1
2
resistance
most effected by diameter of the airway
Dalton's law
total pressure of a gas is equal to the sum of pressures each gas exerts independently
O
2
= 20.93% or 0.2093
N
2
= 79.04% or 0.7904
CO
2
= 0.03% or 0.0003
atmospheric pressure
= 760 mmHg
X
= 159.1 mmHg
= 600.7 mmHg
= 0.228 mmHg
760 mmHg
Fick's law of diffusion
V gas =
A
T
x
D
x
(P - P )
1
2
area
thickness
diffusion coefficient
difference in pressure
Blood flow to the lung
same volume as systemic circulation
drastically lower pressure
however...
primarily due to low resistance
results in inequality of blood flow to different areas of the lung due to gravity
ideal ratio of perfusion to ventilation is 1:1
rarely occurs due to mismatch of blood flow and ventilation
potential for poor gas exchange in areas of the lung
light to moderate exercise improves V/Q ratio
heavy exercise results in slight inequality
O and CO transport in blood
2
2
Hemoglobin & O transport
2
99% of oxygen in blood is bound to hemoglobin
oxyhemoglobin
deoxyhemoglobin
normal concentration of hemoglobin:
males:
females:
150 g/L
130 g/L
1 g of hemoglobin can carry 1.34 mL O
2
so...
males:
200 mL O /L
females:
174 mL O /L
2
2
if 100% saturated
Muscle
(tissue)
3 methods of CO transport
2
1. dissolved
~ 10%
2. bound to hemoglobin
~ 20%
carbaminohemoglobin
3. bicarbonate transport
~ 70%
CO
2
+
H O
2
H CO
2
3
carbonic anhydrase
HCO
3
-
+
H
+
"bicarbonate"
tissue
RBC
plasma
accompanied by "chloride shift"
H removed from hemoglobin by newly-bound O
+
2
H + HCO
+
3
-
H CO
2
3
low PCO in alveolus results in dissociation to CO and H O
2
2
2
H CO
CO + H O
2
3
2
2
CO diffuses into alveolus and is exhaled
2
Control of ventilation
Pons
Medulla Oblongata
preBotzinger Complex
retrotrapezoid nucleus
pneumotaxic center
caudal pons
group pacemaker hypothesis
4 rhythm centers interact to regulate breathing
at rest, dominated by preBotC
redundant control
influenced by neural and blood-borne input
Efferent
"spill-over" from motor cortex could increase ventilation
proportional to amount of work being done
Afferent
neural signals from muscles (spindles, GTOs, chemoreceptors) relayed to brain could alter ventilation
Central chemoreceptors
located in medulla
affected by changes in PCO and H in the cerebrospinal fluid
2
+
Peripheral chemoreceptors
located in:
bifurcation of carotid artery
aortic arch
respond to increases in H and PCO
respond to increases in H and PCO
respond to increased K and decreased PO
+
2
+
+
2
2
PCO
2
,
ventilation
PO
2
,
ventilation
(eventually)
at sea level
incremental exercise
CO + H O
2
2
H CO
2
H + HCO
3
3
+
-
Full transcript