Transport in Animals. Gastrovascular cavities. Nutrients and gases can move by processes such as diffusion and active transport.

Transcription

1 Transport in Animals Gastrovascular cavities flatworms and cnidarians Nutrients and gases can move by processes such as diffusion and active transport.

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3 Figure 42.1 Internal transport in the cnidarian Aurelia

4 b. c. Copyright The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Gastrovascular cavity Water No Circulatory System Sponge Hydra Nematode Water Osculum (excurrent opening) Incurrent pore Water Water Gastrovascular cavity Water Anus Mouth Water a. Gastrovascular cavity Open Circulation Grasshopper Heart Closed Circulation Earthworm Lateral hearts Heart Hemolymph

5 Open Circulatory systems Insects, other arthropods and most mollusks No distinction between blood and the interstitial fluid

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7 Open Circulatory systems Hemolymph name of general body fluid directly bathes the internal organs System of sinuses Heart and body movements cause circulation

8 Open Circulatory systems Slower circulation sluggish animals BUT... Insects are very active

9 Figure 42.2 Open and closed circulatory systems

10 Closed Circulatory Systems Earthworms, squids, octopuses, and vertebrates Blood is confined to vessels and is distinct from interstitial fluid Consists of the heart, blood vessels and blood

11 Blood Plasma about 55% of blood volume 90% water inorganic salts (electrolytes), metabolites (vitamins, aa, glucose), wastes & hormones proteins osmotic balance, viscosity buffers, transport lipids, antibodies, clotting factors (fibrinogen)

12 Copyright The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Plasma Red blood cells Platelets White blood cells Formed elements Plasma (92% water, 55% of whole blood) Platelets and leukocytes (<1%) Red blood cells (erythrocytes) (45% of whole blood) Blood Plasma Plasma proteins (7%) Albumin (54%) Globulins (38%) Fibrinogen (7%) All others (1%) Water (91.5%) Other solutes (1.5%) Electrolytes Nutrients Gases Regulatory substances Waste products Monocytes Red Blood Cells 4 million 6 million/ mm 3 blood Neutrophils Basophils Platelets 150, ,000 mm 3 blood Eosinophils 60 70% 2 4% Lymphocytes 3 8% 0.5 1% 20 25%

13 Figure 42.14x Blood smear

14 Blood Cellular Elements: Red Blood Cells (Erythrocytes) Most numerous (5-6 million in one cubic ml) Transport oxygen & carbon dioxide

15 Cellular Elements: Blood White Blood Cells (Leukocytes) Function in body s defense A cubic ml of blood has about 5,000 10,000 in interstitial fluid or in the lymphatic system where your body fights pathogens

16 Cellular Elements: Blood Platelets are cell fragments that pinch off from larger cells in the bone marrow -Function in the formation of blood clots Prothrombin Thrombin Fibrinogen Fibrin Thrombin 1. Vessel is damaged, exposing surrounding tissue to blood. 2. Platelets adhere and become sticky, forming a plug. 3. Cascade of enzymatic reactions is triggered by platelets, plasma factors, and damaged tissue. 4. Threads of fibrin trap erythrocytes and form a clot. 5. Once tissue damage is healed, the clot is dissolved.

17 Figure 42.16x Blood clot

18 Heart one atrium or two atria one or two ventricles

19 Heart one atrium or two atria chambers that receive blood returning to the heart one or two ventricles chambers that pump blood out of the heart.

20 Blood vessels Arteries branch into arterioles Capillaries Veins venules merge into veins

21 Blood vessels Arteries branch into arterioles carry blood away from heart Capillaries materials are exchanged Veins venules merge into veins carry blood back toward heart

22 Blood Vessel Structure Walls of arteries or veins have three layers: epithelium smooth muscle with elastic fibers connective tissue Arteries have thicker walls than veins Capillaries only have the inner epithelium layer

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24 Capillary Exchange Law of Continuity blood flows slowly in capillaries because larger total cross-section allows materials to be exchanged

25 Figure The interrelationship of blood flow velocity, cross-sectional area of blood vessels, and blood pressure

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27 Capillary Exchange About 85% of the fluid that exits capillaries re-enters at the venule end.

28 Return of Blood to Heart Pressure too low in veins contraction of skeletal muscles move blood one-way valves in veins prevent backflow

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30 FISH Variation in Vertebrate Circulation Two chambered heart and a single circuit of blood flow

31 Vertebrate Circulatory Systems Copyright The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Systemic capillaries Atrium Respiratory capillaries Gills Body Sinus venosus Ventricle Conus arteriosus

32 AMPHIBIAN Variation in Vertebrate Circulation Three chambered heart (two atria and one ventricle) and double circulation (two circuits of flow)

33 Amphibian Circulation Copyright The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Carotid artery Systemic artery Pulmocutaneous artery Truncus arteriosus Aorta Pulmonary capillaries Lungs Right atrium Conus arteriosus Pulmonary vein Sinus venosus Left atrium Left atrium Right atrium Conus arteriosus Ventricle Ventricle Posterior vena cava Systemic capillaries Body a. b.

34 AMPHIBIAN Variation in Vertebrate Pulmonary circuit Circulation blood is pumped to the lungs, where it is oxygenated and carried back to the left atrium Systemic circuit blood is pumped to the rest of the body, where it gives up oxygen and is carried back to the right atrium

35 AMPHIBIAN Variation in Vertebrate Circulation Double circulation assures a vigorous flow of blood to the vital organs single ventricle --some mixing of oxygenrich and oxygen-poor blood.

36 Variation in Vertebrate Circulation MAMMALS & BIRDS Have a four chambered heart and double circulation The left side of the heart handles oxygenrich blood and the right side handles only oxygen-poor blood.

37 Copyright The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Head Systemic capillaries Aorta Lungs Superior vena cava Pulmonary artery Respiratory capillaries Pulmonary semilunar valve Right atrium Tricuspid valve Right ventricle Pulmonary veins Left atrium Bicuspid mitral valve Left ventricle Pulmonary artery Superior vena cava Inferior vena cava Body Pulmonary vein Aorta Artery Inferior vena cava Systemic capillaries a. b.

38 Mammalian or Bird Heart Valves prevent backflow of blood when the ventricles contract Between each ventricle and atrium is an atrioventricular (AV) valve tricuspid and bicuspid (mitral) At the exits of the heart are the semilunar valves

39 Copyright The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Head Systemic capillaries Aorta Lungs Superior vena cava Pulmonary artery Respiratory capillaries Pulmonary semilunar valve Right atrium Tricuspid valve Right ventricle Pulmonary veins Left atrium Bicuspid mitral valve Left ventricle Pulmonary artery Superior vena cava Inferior vena cava Body Pulmonary vein Aorta Artery Inferior vena cava Systemic capillaries a. b.

40 Millivolts Copyright The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Right atrium SA node (pacemaker) AV node AV bundle Left atrium Interventricular septum Internodal pathway AV AV bundle Purkinje fibers Purkinje fibers Left and right bundle branches 1. The impulse begins at the SA node and travels to the AV node. 2. The impulse is delayed at the AV node. It then travels to the AV bundle. AV bundle Interventricular septum 3. From the AV bundle, the impulse travels down the interventricular septum. Left and right bundle branches 4. The impulse spreads to branches from the interventricular septum. +1 R Purkinje fibers 5. Finally reaching the Purkinje fibers, the impulse is distributed throughout the ventricles. The control of heart rhythm 0 P wave Q S T wave 1 sec -1 Seconds

41 Cardiac Cycle a complete sequence of the heart contracting to pump blood, relaxing to fill with blood. total length is about 0.8 s The contraction phase is called systole The relaxation phase is called diastole

42 Figure 42.6 The cardiac cycle

43 Copyright The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Blood pressure gauge Cuff Stethoscope 1. Cuff pressure: 150 mm Hg No sound: Artery closed 2. Cuff pressure: 120 mm Hg Pulse sound: Systolic pressure 3. Cuff pressure: 75 mm Hg Sound stops: Diastolic pressure