Transcript A closed circulatory system

Chapter 42: Circulation and Gas Exchange
1. What is the function of the circulatory system?
- Transport nutrients & O2 to all cells
- Transport metabolic waste to kidneys & CO2 to lungs
2. What is the difference between a gastrovascular cavity and an open
& closed circulatory system?
- Gastrovascular cavity
- digestion & distribution of nutrients
- 2 cell layered thick organisms – Cnidarians
Figure 42.2 Internal transport in the cnidarian Aurelia
Circular
canal
Mouth
Radial canal
5 cm
Chapter 42: Circulation and Gas Exchange
1. What is the function of the circulatory system?
- Transport nutrients & O2 to all cells
- Transport metabolic waste to kidneys & CO2 to lungs
2. What is the difference between a gastrovascular cavity and an open
& closed circulatory system?
- Gastrovascular cavity
- digestion & distribution of nutrients
- 2 cell layered thick organisms – Cnidarians
- Animals with more than 2 cell layers need more
Figure 42.3 Open and closed circulatory systems
Heart
Hemolymph in sinuses
surrounding ograns
Anterior Lateral
vessel vessels
Heart
Interstitial
fluid
Small branch vessels
in each organ
Ostia
Dorsal vessel
(main heart)
Tubular heart
(a) An open circulatory system
-Heart pump hemolymph into
large cavity
-VERY inefficient due to mixing of
good & bad substances
Auxiliary
hearts
Ventral
vessels
(b) A closed circulatory system
-Heart pump blood through
vessels in a complete circuit
-More efficient & consistent
Chapter 42: Circulation and Gas Exchange
1. What is the function of the circulatory system?
- Transport nutrients & O2 to all cells
- Transport metabolic waste to kidneys & CO2 to lungs
2. What is the difference between a gastrovascular cavity and an open
& closed circulatory system?
- Gastrovascular cavity
- digestion & distribution of nutrients
- 2 cell layered thick organisms – Cnidarians
- Animals with more than 2 cell layers need more
3. Let’s compare some vertebrate hearts
Figure 42.4 Vertebrate Circulatory Systems
FISH
AMPHIBIANS
REPTILES (EXCEPT BIRDS)
MAMMALS AND BIRDS
Lung and skin capillaries
Lung capillaries
Lung capillaries
FISHES
Gill capillaries
Artery
Pulmocutaneous
circuit
Gill
circulation
Heart:
ventricle (V)
A
Atrium (A)
Systemic
circulation
Vein
Systemic capillaries
A
V
Left
Right
Systemic
circuit
Systemic capillaries
Right
systemic
aorta
Pulmonary
circuit
A
V
Right
Pulmonary
circuit
Left
Systemic
V aorta
Left
A
Systemic capillaries
A
V
Right
A
V
Left
Systemic
circuit
Systemic capillaries
- 1atrium & 1 ventricle
- BP is LOW after gill capillaries
- Swimming helps blood complete the circuit
- single circuit
- blood flows from gills directly to rest of the body
Figure 42.4 Vertebrate Circulatory Systems
AMPHIBIANS
AMPHIBIANS
REPTILES (EXCEPT BIRDS)
MAMMALS AND BIRDS
Lung and skin capillaries
Lung capillaries
Lung capillaries
FISHES
Gill capillaries
Artery
Pulmocutaneous
circuit
Gill
circulation
Heart:
ventricle (V)
A
Atrium (A)
Systemic
circulation
Vein
Systemic capillaries
A
V
Left
Right
Systemic
circuit
Systemic capillaries
Right
systemic
aorta
Pulmonary
circuit
A
V
Right
Pulmonary
circuit
Left
Systemic
V aorta
Left
A
Systemic capillaries
A
V
Right
A
V
Left
Systemic
circuit
Systemic capillaries
- 2 atria & 1 ventricle
- Mixing of blood in ventricle is INEFFICIENT
- Double circulation
- blood flows from ventricle to pulmocutaneous circuit, back to the heart
& then from the same ventricle to the systemic capillaries
Figure 42.4 Vertebrate Circulatory Systems
REPTILES
AMPHIBIANS
REPTILES (EXCEPT BIRDS)
MAMMALS AND BIRDS
Lung and skin capillaries
Lung capillaries
Lung capillaries
FISHES
Gill capillaries
Artery
Pulmocutaneous
circuit
Gill
circulation
Heart:
ventricle (V)
A
Atrium (A)
Systemic
circulation
Vein
Systemic capillaries
A
V
Left
Right
Systemic
circuit
Systemic capillaries
Right
systemic
aorta
Pulmonary
circuit
A
V
Right
Pulmonary
circuit
Left
Systemic
V aorta
Left
A
Systemic capillaries
A
V
Right
A
V
Left
Systemic
circuit
Systemic capillaries
- 2 atria & 1 ventricle
- Mixing of blood in ventricle is less
- pulmonary circuit since skin is dry
- 90% ridge between right & left ventricles
- ridge is complete in crocodilians
Figure 42.4 Vertebrate Circulatory Systems
MAMMALS
AMPHIBIANS
REPTILES (EXCEPT BIRDS)
MAMMALS AND BIRDS
Lung and skin capillaries
Lung capillaries
Lung capillaries
FISHES
Gill capillaries
Artery
Pulmocutaneous
circuit
Gill
circulation
Heart:
ventricle (V)
A
Atrium (A)
Systemic
circulation
Vein
Systemic capillaries
A
V
Left
Right
Systemic
circuit
Systemic capillaries
Right
systemic
aorta
Pulmonary
circuit
A
V
Right
Pulmonary
circuit
Left
Systemic
V aorta
Left
A
Systemic capillaries
- 2 atria & 2 ventricles
- no mixing of O2-rich & O2 poor blood
- 2 complete circuits – pulmonary & systemic
A
V
Right
A
V
Left
Systemic
circuit
Systemic capillaries
Chapter 42: Circulation and Gas Exchange
1. What is the function of the circulatory system?
- Transport nutrients & O2 to all cells
- Transport metabolic waste to kidneys & CO2 to lungs
2. What is the difference between a gastrovascular cavity and an open
& closed circulatory system?
- Gastrovascular cavity
- digestion & distribution of nutrients
- 2 cell layered thick organisms – Cnidarians
- Animals with more than 2 cell layers need more
3. Let’s compare some vertebrate hearts
4. What is the route of blood flow through our circulatory system?
Figure 42.5 The mammalian cardiovascular system: an overview
7
Capillaries of
head and
forelimbs
Anterior
vena cava
Pulmonary
artery
Pulmonary
artery
Aorta
9
6
Capillaries
of right lung
Capillaries
of left lung
2
4
3
Pulmonary
vein
Right atrium
3
11
5
1
Left atrium
Pulmonary
vein
10
Left ventricle
Right ventricle
Aorta
Posterior
vena cava
8
Capillaries of
abdominal organs
and hind limbs
Chapter 42: Circulation and Gas Exchange
1. What is the function of the circulatory system?
2. What is the difference between a gastrovascular cavity and an open
& closed circulatory system?
3. Let’s compare some vertebrate hearts
4. What is the route of blood flow through our CV system?
1. Right ventricle
2. Pulmonary artery
3. Pulmonary capillaries
4. Left atrium
5. Left ventricle
6. Aorta
7. Capillaries above heart – head & arms
8. Capillaries below heart – abdominal organs & legs
9. Anterior vena cava – from above heart
10. Posterior vena cava – from below heart
11. Right atrium
5. How does structure fit function of the heart?
Figure 42.6 The mammalian heart: a closer look
Aorta
Pulmonary artery
Pulmonary
artery
Anterior vena cava
Right atrium
Left
atrium
Pulmonary
veins
Pulmonary
veins
Semilunar
valve
Semilunar
valve
Atrioventricular
valve
Atrioventricular
valve
Posterior
vena cava
Right ventricle
Left ventricle
Chapter 42: Circulation and Gas Exchange
1. What is the function of the circulatory system?
2. What is the difference between a gastrovascular cavity and an open
& closed circulatory system?
3. Let’s compare some vertebrate hearts
4. What is the route of blood flow through our CV system?
5. How does structure fit function of the heart?
- Atria have thin walls – only pump to ventricles below
- Ventricles have THICK walls – left is thickest
- Valves prevent back flow
- Atrioventricular valves – between atria & ventricles
- Semilunar valves - between ventricles & exit vessels
6. How is the heart beat controlled?
Figure 42.8 The control of heart rhythm
1 Pacemaker generates
wave of signals
to contract.
SA node
(pacemaker)
2 Signals are delayed
3 Signals pass
to heart apex.
at AV node.
AV node
throughout
ventricles.
Bundle
branches
Heart
apex
ECG
4 Signals spread
Purkinje
fibers
Chapter 42: Circulation and Gas Exchange
1. What is the function of the circulatory system?
2. What is the difference between a gastrovascular cavity and an open
& closed circulatory system?
3. Let’s compare some vertebrate hearts
4. What is the route of blood flow through our CV system?
5. How does structure fit function of the heart?
- Atria have thin walls – only pump to ventricles below
- Ventricles have THICK walls – left is thickest
- Valves prevent back flow
- Atrioventricular valves – between atria & ventricles
- Semilunar valves - between ventricles & exit vessels
6. How is the heart beat controlled?
7. How does blood flow through our vessels?
Figure 42.9 The structure of blood vessels
Artery
Vein
Basement
membrane
Endothelium
100 µm
Valve
Endothelium
Smooth
muscle
Endothelium
Capillary
Connective
tissue
Smooth
muscle
Connective
tissue
Artery
Vein
Venule
Arteriole
Figure 42.10 Blood flow in veins
Direction of blood flow
in vein (toward heart)
Valve (open)
Skeletal muscle
Valve (closed)
Chapter 42: Circulation and Gas Exchange
1. What is the function of the circulatory system?
2. What is the difference between a gastrovascular cavity and an open
& closed circulatory system?
3. Let’s compare some vertebrate hearts
4. What is the route of blood flow through our CV system?
5. How does structure fit function of the heart?
6. How is the heart beat controlled?
7. How does blood flow through our vessels?
8. What is the relationship between vessel size, BP & velocity?
5,000
4,000
3,000
2,000
1,000
0
50
40
30
20
10
0
Systolic
pressure
Venae cavae
Veins
Venules
Capillaries
Arterioles
Diastolic
pressure
Arteries
120
100
80
60
40
20
0
Aorta
- Slow flow means better ability for exchange
Velocity (cm/sec)
- Cells flow through single file
Pressure (mm Hg)
- Capillaries increase surface area
Area (cm2)
Figure 42.11 The interrelationship of blood flow velocity, crosssectional area of blood vessels, and blood pressure
Figure 42.14 Fluid exchange between capillaries and the interstitial fluid
Tissue cell
Capillary
Red
blood
cell
Net fluid
movement out
Net fluid
movement in
15 m
At the arterial end of a
capillary, blood pressure is
greater than osmotic pressure,
and fluid flows out of the
capillary into the interstitial fluid.
Direction of
blood flow
Pressure
Capillary
INTERSTITIAL FLUID
Blood pressure
Osmotic pressure
Inward flow
Outward flow
Arterial end of capillary
Venule end
At the venule end
of a capillary, blood
pressure is less than
osmotic pressure, and
fluid flows from the
interstitial fluid into
the capillary.
Chapter 42: Circulation and Gas Exchange
1. What is the function of the circulatory system?
2. What is the difference between a gastrovascular cavity and an open
& closed circulatory system?
3. Let’s compare some vertebrate hearts
4. What is the route of blood flow through our CV system?
5. How does structure fit function of the heart?
6. How is the heart beat controlled?
7. How does blood flow through our vessels?
8. What is the relationship between vessel size, BP & velocity?
9. What is blood made of?
Figure 42.15 The composition of mammalian blood
Plasma 55%
Constituent
Major functions
Water
Solvent for
carrying other
substances
Icons (blood electrolytes
Sodium
Potassium
Calcium
Magnesium
Chloride
Bicarbonate
Plasma proteins
Albumin
Fibringen
Osmotic balance
pH buffering, and
regulation of
membrane
permeability
Cellular elements 45%
Cell type
Erythrocytes
(red blood cells)
Separated
blood
elements
Functions
Number
per L (mm3) of blood
Leukocytes
(white blood cells)
5–6 million
Transport oxygen
and help transport
carbon dioxide
5,000–10,000
Defense and
immunity
Osmotic balance,
pH buffering
Clotting
Immunoglobulins
Defense
(antibodies)
Substances transported by blood
Nutrients (such as glucose, fatty acids, vitamins)
Waste products of metabolism
Respiratory gases (O2 and CO2)
Hormones
Lymphocyte
Basophil
Eosinophil
Neutrophil
Platelets
Monocyte
250,000
400,000
Blood clotting
Chapter 42: Circulation and Gas Exchange
1. What is the function of the circulatory system?
2. What is the difference between a gastrovascular cavity and an open
& closed circulatory system?
3. Let’s compare some vertebrate hearts
4. What is the route of blood flow through our CV system?
5. How does structure fit function of the heart?
- Atria have thin walls – only pump to ventricles below
- Ventricles have THICK walls – left is thickest
- Valves prevent back flow
- Atrioventricular valves – between atria & ventricles
- Semilunar valves - between ventricles & exit vessels
6. How is the heart beat controlled?
7. How does blood flow through our vessels?
8. What is the relationship between vessel size, BP & velocity?
9. What is blood made of?
10. Where do blood cells originate?
Figure 42.16 Differentiation of blood cells
Pluripotent stem cells
(in bone marrow)
Ch 43
Lymphoid
stem cells
Myeloid
stem cells
Basophils
B cells
T cells
Lymphocytes
Eosinophils
Neutrophils
Erythrocytes
Platelets
Monocytes
Erythropoeitin (EPO) – kidney hormone released in response to low O2 to stimulate
production of erythrocytes
Chapter 42: Circulation and Gas Exchange
1. What is the function of the circulatory system?
2. What is the difference between a gastrovascular cavity and an open
& closed circulatory system?
3. Let’s compare some vertebrate hearts
4. What is the route of blood flow through our CV system?
5. How does structure fit function of the heart?
6. How is the heart beat controlled?
7. How does blood flow through our vessels?
8. What is the relationship between vessel size, BP & velocity?
9. What is blood made of?
10. Where do blood cells originate?
11. How does blood clot?
Figure 42.17 Blood clotting
2 The platelets form a
1 The clotting process begins
plug that provides
emergency protection
against blood loss.
when the endothelium of a
vessel is damaged, exposing
connective tissue in the
vessel wall to blood. Platelets
adhere to collagen fibers in
the connective tissue and
release a substance that
makes nearby platelets sticky.
3 This seal is reinforced by a clot of fibrin when
vessel damage is severe. Fibrin is formed via a
multistep process: Clotting factors released from
the clumped platelets or damaged cells mix with
clotting factors in the plasma, forming an
activation cascade that converts a plasma protein
called prothrombin to its active form, thrombin.
Thrombin itself is an enzyme that catalyzes the
final step of the clotting process, the conversion of
fibrinogen to fibrin. The threads of fibrin become
interwoven into a patch (see colorized SEM).
Collagen fibers
Platelet releases chemicals
that make nearby platelets sticky
Platelet
plug
Fibrin clot
Clotting factors from:
Platelets
Damaged cells
Plasma (factors include calcium, vitamin K)
Prothrombin
Thrombin
Fibrinogen
Fibrin
5 µm
Red blood cell
Chapter 42: Circulation and Gas Exchange
1. What is the function of the circulatory system?
2. What is the difference between a gastrovascular cavity and an open
& closed circulatory system?
3. Let’s compare some vertebrate hearts
4. What is the route of blood flow through our CV system?
5. How does structure fit function of the heart?
6. How is the heart beat controlled?
7. How does blood flow through our vessels?
8. What is the relationship between vessel size, BP & velocity?
9. What is blood made of?
10. Where do blood cells originate?
11. How does blood clot?
12. What are some CV diseases?
- >50% of deaths due to CV disease
- LDLs – low-density lipoproteins - bad cholesterol
- Associated with arterial plaques
- HDLs – high-density lipoproteins – good cholesterol
- Reduce deposition of cholesterol
Figure 42.18 Atherosclerosis
Connective
tissue
Smooth muscle
Endothelium
(a) Normal artery
50 µm
Plaque
(b) Partly clogged artery
250 µm
- Atherosclerosis – cholesterol plaques in arteries slows blood flow
- Arteriosclerosis – hardening of the arteries due to Ca+2 added to plaques
Chapter 42: Circulation and Gas Exchange
1. What is the function of the circulatory system?
2. What is the difference between a gastrovascular cavity and an open
& closed circulatory system?
3. Let’s compare some vertebrate hearts
4. What is the route of blood flow through our CV system?
5. How does structure fit function of the heart?
6. How is the heart beat controlled?
7. How does blood flow through our vessels?
8. What is the relationship between vessel size, BP & velocity?
9. What is blood made of?
10. Where do blood cells originate?
11. How does blood clot?
12. What are some CV diseases?
- LDLs – low-density lipoproteins - bad cholesterol
- HDLs – high-density lipoproteins – good cholesterol
- Hypertension – high BP
- Heart attack – death of heart muscle due to blocked coronary arteries
- Stroke – death of nervous tissue in brain due to blocked brain arteries