1. Transport systems in animals

2. We’ll be discussing Reptiles Birds Mammals
Functions of a transport/circulatory system
Invertebrate circulation
Diffusion
Aided by gastrovascular cavity
Water vascular system
Open circulatory system
Closed circulatory system
Vertebrate circulation
Fishes
Amphibians
Reptiles
Birds
Mammals
Pathway of blood
Cardiac cycle
Maintenance of heartbeat
Principles governing blood circulation
Lymphatic system
Blood composition and function
Cardiovascular disease

3. Functions of the circulatory system
Transports materials
Nutrients from digested food
Respiratory gases: CO2 and O2
Waste materials: toxins and nitrogenous wastes
Antibodies
Hormones
Enzymes
Immune functions
Maintains homeostasis
Blood pH
Heat transport

4. How are materials transported in multicellular organisms
How are materials transported in multicellular organisms? Phylum Porifera

5. How are materials transported in multicellular organisms?
Gastrovascular cavity in simple invertebrates
Cnidarians (e.g. Hydra) and flatworms (e.g. planarians)
No system required
Single opening: exchange of materials with the environment
Central cavity for digestion and distribution of substances throughout the body
Body walls two cell layers thick  materials undergo diffusion

6. How are materials transported in multicellular organisms?
Water vascular system in echinoderms
multi-purpose: locomotion, food and waste transport, respiration
movement of muscles pump water into canals
closed system of canals connecting tube feet
madreporite  ring canal  radial and lateral canal  tube feet  ampullae

7. How are materials transported in multicellular organisms?
Open circulatory system
Phylum Arthropoda, Phylum Mollusca (with one exception)
hemolymph
heart(s)  sinuses  ostia  heart(s)
diffusion from sinuses to organs
often serve a support purpose
disadvantage: loss of pressure in sinuses
insects: well-developed respiratory systems, O2 not transported through the blood

8. How are materials transported in multicellular organisms?
Closed circulatory system or cardiovascular system
cephalopods, annelids, vertebrates
presence of blood vessels
advantages
rapid flow
may direct blood to specific tissues
blood cells and large molecules remain within vessels
can support higher levels of metabolic activity

9. General plan of the cardiovascular system
Heart
Atrium
Ventricle
Blood vessels
Arteries
Arterioles
Capillaries and capillary beds
Venules
Veins
Blood

10. Vertebrate adaptations of the cardiovascular system
FISHES
Single-circulation
Fish heart
2-chambered
atrium and ventricle
African lungfish heart
3-chambered
2 atria
LA: O2-rich blood
RA: O2-poor blood
spiral fold
partially divided ventricle

11. Vertebrate adaptations of the cardiovascular system
Amphibians
Pulmocutaneous and systemic circulation are partly separated
Amphibian heart
1 ventricle
2 atria:
LA: O2-rich blood
RA: O2-poor blood
advantage: oxygen-rich blood reaches the body’s organs faster
disadvantage: some mixing of O2-rich and poor blood occurs

12. Vertebrate adaptations of the cardiovascular system
Reptiles
Reptilian heart
3-chambers (crocodilians have 4)
2 atria
1 ventricle (2 in crocodiles and alligators)
partially divided, decreases mixing

13. Vertebrate adaptations of the cardiovascular system
Birds and Mammals
4 chambered heart:
2 atria
2 ventricles
full separation of pulmonary and systemic circuits
Advantages
no mixing of oxygenated and deoxygenated blood
gas exchange is maximized
pulmonary and systemic circuits operate at different pressures
Importance
Endothermic  high nutrient and O2 demands in tissues
Numerous vessels  great deal of resistance, so requires high pressure

14. Blood flow in mammals R side of heart: L side of heart:
pulmonary circuit
L side of heart:
systemic circuit
one way valves:
atrioventricular valves
semilunar valves

15. Blood flow in mammals
right atrium receives O2- poor blood from superior and inferior venae cavae
from right atrium into the right ventricle through the tricuspid valve
pumped into the pulmonary artery through the pulmonary semilunar valve to lungs
O2-rich blood from lungs is returned to the left atrium via the pulmonary veins
enters the left ventricle via the mitral or bicuspid valve
exits the left ventricle into the aorta via the aortic semilunar valve
circulated to body tissues