Circulation & Gas Exchange

1
Chapter 42
Circulation Gas Exchange
2
Functions of the Circulatory System

• Transport oxygen to cells
• Transport nutrients from the digestive system to
  body cells
• Transport hormones to body cells
• Transport waste from body cells to excretory
  organs
• Distribute body heat

3
Gastrovascular Cavity of Aurelia
4
Open Circulatory System
5
Closed Circulatory System
6
Ventricle
Atrium
7
Circulatory Systems in Fish, Amphibian, Mammal
Endotherm
Ectotherms
8
(No Transcript)
9
(No Transcript)
10
(No Transcript)
11
(No Transcript)
12
Electrocardiogram (ECG)

• P atrial depolarization 0.1 sec atria
  contracts
• QRS ventricular depolarization ?ventricles
  contract (lub), contraction stimulated by Ca
  uptake
• T ventricular repolarization ? ventricles relax
  (dub)

13
Vein
Artery
Tunica intima
Valve
Tunica media
Tunica externa
14
Artery
vein
15
Arteries

• Carry blood away from the heart.
• Thick-walled to withstand hydrostatic pressure of
  the blood during ventricular systole.
• Blood pressure pushes blood through arteries.

16
Veins

• Carry blood to the heart.
• Thinner-walled than arteries.
• Possess one-way valves that prevent backwards
  flow of blood.
• Blood flow due to body movements, not from blood
  pressure.

17
One-Way Valves in Veins
18
Capillaries
capillary vessel
19
(No Transcript)
20
(No Transcript)
21
(No Transcript)
22
Lymph Transport

• lacks pump for circulation
• relies on activity of skeletal muscles and
  pulsation of nearby arteries for movement of
  fluid
• 3L of lymph enters blood stream every 24 hrs
• proteins easily enter lymphatic system
• uptake of large particles such as cell debris,
  pathogens, and cancer cells
• lymph nodes where it is cleansed of debris and
  examined by cells of the immune system (WBC)

23
Formation of Lymph
24
Sphygnomamometer
25
Measuring Blood Pressure
26
(No Transcript)
27
Superficial Pulse Points- arteries, not veins
temporal
60 beats/minute
facial
carotid

• Temporal artery
• Facial artery
• Common carotid artery
• Brachial artery
• Radial artery
• Femoral artery
• Popliteal artery
• Posterior tibial artery
• Dorsal pedis artery

brachial
radial
femoral
popliteal
Posterior tibial
Dorsal pedis
28
Blood
Artery
White blood cells
Platelets
Red blood cells
29
Function Blood

• Deliver O2
• Remove metabolic wastes
• Maintain temperature, pH, and fluid volume
• Protection from blood loss- platelets
• Prevent infection- antibodies and WBC
• Transport hormones

30
Blood
Plasma-55
Buffy coat-lt1
Formed elements-45
31

Blood Plasma Components-55

• 90 Water
• 8 Solutes
• Proteins
• Albumin (60 )
• Alpha and Beta Globulins
• Gamma Globulins
• fibrinogens
• Gas
• Electrolytes

32
Blood Plasma Components

• Organic Nutrients
• Carbohydrates
• Amino Acids
• Lipids
• Vitamins
• Hormones
• Metabolic waste
• CO2
• Urea

33
Buffy Coat- lt1

• Leukocytes
• Platelets

34
Formed Elements of the Blood-45

• Erythrocytes (red blood cells)
• Leukocytes (white blood cells)
• Platelets

35
Erythrocytes
36
Erythrocyte?7.5?m in dia    Anucleate- so can't
reproduce however, repro in red bone marrow   
Hematopoiesis- production of RBC    Function-
transport respiratory gases    Hemoglobin-
quaternary structure, 2 ? chains and 2 ?
chains    Lack mitochondria. Why?   1 RBC
contains 250 million hemoglobin
molecules    Men- 5 million cells/mm3    Women-
4.5 million cells/mm3    Life span 100-120 days
and then destroyed in spleen (RBC graveyard)
37
Types of Leukocytes
4,000-11,000 cells/mm 3
Never let monkeys eat bananas

• Granulocytes
• Neutrophils- 40-70
• Eosinophils- 1-4
• Basophils- lt1
• Agranulocytes
• Monocytes- 4-8
• Lymphocytes- 20-45

38
(No Transcript)
39
Leukocyte Squeezing Through Capillary Wall
Diapodisis
40
Fig. 42-21a
Parapodium (functions as gill)
(a) Marine worm
41
Fig. 42-21b
Gills
(b) Crayfish
42
Fig. 42-21c
Coelom
Gills
Tube foot
(c) Sea star
43
Fig. 42-22
Fluid flow through gill filament
Oxygen-poor blood
Anatomy of gills
Oxygen-rich blood
Gill arch
Lamella
Gill arch
Gill filament organization
Blood vessels
Water flow
Operculum
Water flow between lamellae
Blood flow through capillaries in lamella
Countercurrent exchange
PO2 (mm Hg) in water
150
120
90
60
30
Gill filaments
Net diffu- sion of O2 from water to blood
110
80
20
50
140
PO2 (mm Hg) in blood
44

• Countercurrent exchange system

45
Fig. 42-23
Tracheal Systems
Air sacs
Tracheae
External opening
Tracheoles
Mitochondria
Muscle fiber
Body cell
Air sac
Tracheole
Trachea
Body wall
Air
2.5 µm
46
Fig. 42-24
Branch of pulmonary vein (oxygen-rich blood)
Branch of pulmonary artery (oxygen-poor blood)
Terminal bronchiole
Nasal cavity
Pharynx
Larynx
Alveoli
(Esophagus)
Left lung
Trachea
Right lung
Bronchus
Bronchiole
Diaphragm
Heart
SEM
Colorized SEM
50 µm
50 µm
47
Fig. 42-25
Rib cage expands as rib muscles contract
Rib cage gets smaller as rib muscles relax
Air inhaled
Air exhaled
Lung
Diaphragm
EXHALATION Diaphragm relaxes (moves up)
INHALATION Diaphragm contracts (moves down)
48
Fig. 42-26
Air
Air
Anterior air sacs
Trachea
Posterior air sacs
Lungs
Lungs
Air tubes (parabronchi) in lung
1 mm
EXHALATION Air sacs empty lungs fill
INHALATION Air sacs fill
49
Fig. 42-27
Cerebrospinal fluid
Pons
Breathing control centers
Medulla oblongata
Carotid arteries
Aorta
Diaphragm
Rib muscles
50
Uptake of Oxygen by Hemoglobin in the Lungs
O2 binds to hemoglobin to form oxyhemoglobin
High Concentration of O2 in Blood Plasma High pH
of the Blood Plasma
51
O2 pickup CO2 release
52
Unloading of Oxygen from Hemoglobin in the Tissues
When O2 is released?deoxyhemoglobin
Low Concentration of O2 in Blood Plasma Lower pH
of the Blood Plasma
53
O2 release CO2 pickup
54
Carbon Dioxide Chemistry in the Blood
CO2 H2O ? H2CO3 ? HCO3- H
bicarbonate ion
carbonic acid
enzyme carbonic anhydrase
55
Transport of Carbon Dioxide from the Tissues to
the Lungs

• 60-70 as bicarbonate dissolved in the
• plasma (slow reaction)
• 7-10 dissolved in the plasma as CO2
• 20-30 bound to hemoglobin as HbCO2
• CO2 hemoglobin ? HbCO2

56
Haldane Effect
Haldane Effect- the amt of CO2 transported in the
blood is markedly affected by the degree of
oxygenation of the blood The lower the P02 and
hemoglobin saturation w/O2, the more CO2 that can
be carried by the blood
57
7. Deep-diving air-breathers stockpile oxygen and
deplete it slowly
58
7. Deep-diving air-breathers stockpile oxygen and
deplete it slowly

• Adaptations to oxygen conservation
• Oxygen stores 2-3 x more than humans
• Humans 36 of our total O2 in lungs and 51 in
  our blood.
• Weddell seal holds 5 of its O2 in its small
  lungs and stockpiles 70 in the blood.
• Skeletal muscles and blood as primary storage
  site (myoglobin)
• Weddell seal to store about 25 of its O2 in
  muscle, 13 in humans

59
Deep-diving air-breathers stockpile oxygen and
deplete it slowly

• Adaptations to oxygen conservation
• Reduce heart rate when diving (120 beats/min to
  6 b/min)
• seals and sea lions store oxygenated blood in
  their extra-large spleen (which can be 45 of
  their body weight)
• Maintain blood flow to brain, heart

60
Average Dive Times

• Sperm whale 90 minutes to 2 hrs
• Northern elephant seal 20 to 35 minutes
• Harbor seal 3 to 7 minutes
• Walrus 10 minutes
• Bottlenose dolphin 8 minutes
• Killer whale 10 minutes
• Amazon river dolphin 2 minutes
• Loggerhead turtle 20 minutes