Circulatory Systems
Figure 49.7
• all vertebrate animals have a
closed circulatory system
• heart, blood vessels
• transport gases, nutrients,
wastes
12
Heart
Figure 49.10
14
Heart
• Four chambers
• Thickness of the wall
Left ventricle ﹥ right ventricle
Valves
• Atriovantricular valve:
right– tricuspid valve left-bicuspid valve
surpported by fibrous strings
•
•
Semilunar valve:
pulmonary valve aortic valve
To prevent blood backward movement
Figure 49.9
17
Blood vessels
• Aorta & vena cava—major
artery & vein
• Arterioles--- small arteries
• Venules--- small veins
• Thickness of the wall:
Artery ﹥ vein
•
c. Vein
Systemic capillary exchange
Figure 49.8
• Pulmonary circuit
blood → lungs → heart
• Systemic circuit
blood → heart → body
deoxygenated blood
oxygenated blood
21
Respiratory Systems
22
Figure 44.1b
23
Figure 44.3
24
Figure 44.2
25
26
Surface Area to Volume Ratio
and Biological Form and Function
27
●
Why unicellular organisms (bacteria, yeast,
Paramecium, Cyanobacteria etc. ) are small?
28
Small intestine inner surface
structure
29
Bergmann's rule and Allen's rule
●
●
Bergmann's rule is one of the best-known generalizations in
zoology. It is generally defined as a within-species tendency in
homeothermic (warm-blooded) animals to have increasing body
size with increasing latitude and decreasing ambient temperature.
That is, Bergmann's rule states that among mammals and birds,
individuals of a particular species in colder areas tend to have
greater body mass than individuals in warmer areas.
Allen's rule is a biological rule posited by Joel Asaph Allen in
1877.It states that endotherms from colder climates usually have
shorter limbs (or appendages) than the equivalent animals from
warmer climates.
30
●
●
●
Observe the circulatory system and respiratory
system of fetal pig
Dissect heart and identify different structure of
heart
Homework essay for bonus points （ 5' ） :
How do you understand the surface area to volume
ratio influencing the form and function of
organisms?
31