Circulatory System Cardiovascular System = Heart, blood vessels, and blood -Transports H2O, nutrients, waste, O2, CO2, hormones, and immune cells. -Regulates heat, pH, and pressure. -Associated with lymphatic system. Lymphatic System = Lymphatic vessels, lymphatic hearts, & lymph

Human Cardiovascular

Blood and Blood Vessels

Vascular Terms Anastamosis = intercommunication between separate vessels (net like). Portal System = vessels that carry blood from capillaries to capillaries. Sinus = region for “pooling” of fluids. Aortic arch = arterial arches that extend from ventral to dorsal between pharyngeal openings. Gnathostomes have 6 early in devel.

Vascular Arteries = Large; carry blood away from heart Arterioles = Smaller; carry blood away from heart Capillaries = Very small; gas & nutrient exchange occur here Veinules = Smaller; carry blood to heart Veins = Large; carry blood to heart

Vertebrate Blood Blood = connective tissue; cells (in vertebrates) in a water-based matrix. Plasma = matrix around blood cells. Transports: H2O, nutrients, waste, CO2, hormones Erythrocytes = Contain hemoglobin; transport O2; No nuclei in mammals. Leucocytes = Immune cells. Platelets = Cell fragments, involved in clotting after damage.

Vertebrate Blood Plasma

Hematopoesis – Blood Devel. Hematopoesis = blood development. Blood islands form in splanchnic mesoderm in yolk sac = 1st site of hematopoesis (always nucleate cells). Early fetal human red blood cells have nuclei. Additional stem cells in splanchnic mesoderm around heart migrate to hematopoetic areas (spleen, kidneys, liver, & bone marrow in non-avian amniotes).

Vascular Development Mostly from splanchnic mesoderm. Angiogenesis = blood vessel formation Blood islands in yolk sac merge to form vessels that then extend into rest of embryo. Cardiovascular system starts in yolk sac and spreads to rest of embryo.

Human Blood Islands

Basic Chordate Arterial Circ. Blood moves from posterior and ventral to the pharynx (heart/sinus venosus) Anteriorly under the pharynx (ventral aorta) Dorsolaterally up through the pharynx (pharyngeal/aortic arches) Then to the body anteriorly and posteriorly from the dorsal pharynx (dorsal aorta).

Lancelet Arterial Circulation dorsal aorta (paired - median) sinus venosus (median) ventral aorta (median)

Lancelet Venous Circulation Anterior & posterior cardinal veins (paired) sinus venosus (median) hepatic vein (median)

Lancelet Circulation anterior cardinal vein ventral common cardinal s.v. dorsal aorta ventral s.v. anterior cardinal vein posterior hepatic common cardinal vein

Basic Amniote Circulation

Early Human Embryo Arterial left & right dorsal aortas aortic arch II arch I IV III ventral aorta (truncus arteriosus) umbilical artery heart sinus venosus atrium ventricle bulbis cordis vitelline artery

Early Human Embryo Arterial left & right dorsal aortas IV VI III ventral aorta (truncus arteriosus) umbilical artery heart vitelline artery

Early Human Embryo Arterial descending aorta IV pulmonary VI III carotids ventral aorta (truncus arteriosus) umbilical artery heart vitelline artery

Early Human Embryo Arterial

Embryonic Arteries ventral aorta dorsal aorta I II III IV V VI I II HEART I II III IV V VI

Human Embryonic Arteries external carotid internal carotid common carotid I II descending aorta aortic arch III IV subclavian pulmonary artery VI ductus arteriosus (before birth) HEART

Human Embryonic Arteries

Human Aortic Arches

Human Fetal Circulation Upper Left Arch VI

Early Human Embryo Circulation left & right anterior cardinal veins left & right posterior cardinal veins left & right common cardinal veins ventral aorta (truncus arteriosus) heart sinus venosus atrium ventricle bulbis cordis allantoic (umbilical) veins vitelline (hepatic) veins

Early Human Embryo Circulation azygous vein jugular veins superior vena cava inferior hepatic portal vein left & right anterior cardinal veins left & right posterior cardinal veins heart allantoic (umbilical) veins vitelline (hepatic) veins

Human Anterior Venous Development

Basic Vertebrate Circulation

Blood Vessel Structure Endothelium = simple squamous epithelium lining inside of blood vessels (tunica intima) Tunica externa = fibrous connective tissue surrounding the outside of the vessel Tunica media = between the tunica intima and tunica externa; elastic connective tissue and/or smooth muscle.

Vessel Structure Arteries = Large; carry blood away from heart; thick tunica media composed primarily of smooth muscle; accommodate high blood pressure Capillaries = Very small; gas & nutrient exchange occur here; lack tunica media and tunica externa

Vessel Structure Veins = Vessels that carry blood to the heart; thin tunica media made primarily of connective tissue one-way valves promote the return of blood under low pressure

Vertebrate Vessels artery vein tunica intima (endothelium) capillary

Adult Human Arterial system

Adult Human Arterial system external carotid internal carotid common carotid vertebral subclavian axillary brachial radial ulnar internal thoracic humeral circumflex lateral thoracic aorta* coeliac* superior mesenteric* inferior mesenteric* deep brachial renal gonadal common iliac external iliac internal iliac deep femoral femoral circumflex femoral popliteal anterior tibial posterior tibial

Pulse Points

Carotid & Radial Pulse Points

Human Venous System Azygous vein

Human Venous System

Human Arm Venous System

Human Leg Venous System

Human Varicose veins

Comparative Circulation

Hematopoesis In non-amniotes occurs primarily in the spleen, kidneys, and liver. Especially the spleen. Hagfishes, lampreys, & lungfishes = no spleen In amniotes occurs in bone marrow (especially in humans and other mammals) as well as in other tissues. No bone marrow in birds.

Subphylum Vertebrata Chondrichthys Actinopterygii coelacanth amphibians hagfishes lampreys Mammalia lungfish Reptilia spleen lost * hemato- poesis in marrow discrete spleen blood cells *erythrocytes lack nuclei

Lancelet Circulation

Vertebrate Circulation dorsal aorta external carotid heart ventral aorta Iliac artery subclavian

Vertebrate Circulation anterior & posterior cardinal veins renal portal jugulars heart hepatic portal lateral abdominal vein iliac vein subclavian vein

Aortic Arches Gnathostomes = Arch I lost in adults; 6 arches early in development Sarcopterygiians = Pulmonary arteries from arch VI Tetrapods & Actinopts. = Arch II lost Amniotes = Arch V lost Mammals = left Arch IV forms aorta; right Arch IV forms base of subclavian Birds = right Arch IV forms aorta

Gnathostome Embryo Aortic Arches internal carotid external I II III I II III IV V VI dorsal aorta ventral IV V VI heart dorsal aorta

Chondrichthyan Aortic Arches II III I II III IV V VI IV V VI heart

Teleost Aortic Arches I II III I II III IV V VI IV V VI heart

Lungfish Aortic Arches II III I II III IV V VI IV V VI heart pulmonary artery

Amphibian Aortic Arches internal carotid external I II III I II III IV V VI IV V VI heart pulmonary artery

Lizard Aortic Arches internal carotid external I II III I II III IV V VI IV V VI heart pulmonary artery

Bird Aortic Arches internal carotid external I II III I II III IV V VI heart pulmonary artery

Lepidosaur Aortic Arches internal carotid external I II III I II III IV V VI IV V VI heart pulmonary artery

Mammalian Aortic Arches internal carotid external I II III I II III IV V VI IV V VI heart pulmonary artery

Subphylum Vertebrata Myxini (hagfishes) Chondrichthys Actinopterygii coelacanths amphibians lungfishes lampreys Mammalia Reptilia arch V lost arch II lost arch II lost arch VI forms pulmonary connection arch I lost; 6 arches form in development

Amniota lizards & snakes crocodilians montremes marsupials eutherians turtles lizards & snakes crocodilians birds right arch IV forms aorta left arch IV forms aorta; right arch IV forms right subclavian

Gnathostome Adult Aortic Arches Chondrichthys Actinopterygii lungfishes I lost II gill arch III IV V VI arch & pulmonary artery

Gnathostome Adult Aortic Arches amphibians turtles lizards I lost II III common carotids IV l. and r. aortic arches V aortic arch (lost in frogs) VI aortic arch & pulmonary artery pulmonary artery

Gnathostome Adult Aortic Arches crocodilians birds Mammalia I lost II III common carotids com. carotids / subclavian bases common carotids & ext. carotid base IV l. and r. aortic arches l. lost r. aorta l. aorta r. subclavian V VI pulmonary artery

Venous System Gnathostomes = renal portal vein Tetrapods = inferior vena cava from right hepatic; anterior cardinal veins form internal & external jugular veins Mammals = inferior vena cava connects to & replaces renal portal Some Mammals (humans, cats, etc.) = lose the left anterior cardinal vein (the right anterior cardinal vein = superior vena cava)

Venous System anterior cardinal sinus venosus common hepatic vein posterior common sinus venosus hepatic vein portal

Shark Venous System internal anterior jugular cardinal subclavian posterior common hepatic vein portal renal portal

Amphibian Venous System internal jugular external anterior cardinal subclavian common cardinal hepatic vein posterior cardinal hepatic portal posterior vena cava renal portal iliac

Reptile Venous System internal jugular external anterior cardinal subclavian hepatic vein hepatic portal posterior vena cava renal portal iliac

Mammal Venous System internal jugular external anterior cardinal subclavian hepatic vein hepatic portal posterior vena cava renal vein iliac

Gnathostome Venous System Veins Chondrichthys Actinopterygii lungfishes ant. card. ant. cardinal com. card. com. cardinal post. card. post. cardinal post. cardinal (rt. = posterior “vena cava”) hepatic 2 hepatic veins hep. portal hepatic portal renal port. renal portal

Gnathostome Venous System Veins amphibians turtles Lepidosauria ant. card. ant. cardinal (jugular vein & brachiocephalics) com. card. com. cardinal (s. vena cavas) com. cardinal (s. vena cavas) post. card. post. cardinal l. lost r. azygous vein hepatic l. hepatic vein r. p. vena cava hep. portal hepatic portal renal port. renal portal

Gnathostome Venous System Veins crocodilians birds Mammalia ant. card. ant. cardinal (jugular vein & brachiocephalics) com. card. com. cardinal (s. vena cavas) com. cardinal (s. vena cavas -left s. v. c. lost in some) post. card. l. lost r. azygous vein hepatic l. hepatic vein r. i. vena cava hep. portal hepatic portal renal port. renal portal lost

liver (with hepatic veins) Hepatic Portal Vein Vein from yolk sac to heart (vitelline vein) impinged on by hepatic diverticulum and forms hepatic capillaries. gut liver (with hepatic veins) heart hepatic portal vein vitelline vein (from yolk sac)

Subphylum Vertebrata Chondrichthys Actinopterygii coelacanths amphibians hagfishes lungfishes lampreys Mammalia Reptilia * jugular veins; rt. hepatic = posterior vena cava renal portal; subclavians *renal portal lost

The Heart

Heart Heart = Muscular pump, moves blood via rhythmic contraction. Contraction involuntary & initiated within the heart. (not-neuronal) Modified branching (cardiac) muscle cells transmit contraction signal. Chamber = Cavity for blood collection separated by valves Valves = Flaps of tissue that prevent back-flow of fluid (in this case blood)

Human Heart Development Formed from splanchnic mesoderm. Endocardial tissue = forms simple squamous epithelium that lines the heart chambers and forms the heart valves Myocardial = epithelium forms heart muscle Hollow endocardial primordia form by splanchnic mesoderm ingression, then fuse to form a the endocardium (endothelium). Epithelial splanchnic mesoderm surrounds the endocardium forming the cardiac muscle of the myocardium.

Human Heart Development endocardium myocardium

Human Heart Development (ventral aorta) Sinus Venosus

Heart Chambers & Valves Sinus venosus = slightly muscular chamber; receives blood from cardinal veins = sinoatrial node (“pacemaker”) in amniotes. Sinoatrial valve = between s.v. & atrium. Atrium = slightly muscular chamber. Atrioventricular valve = between atrium & ventricle. Ventricle = highly muscular chamber. Conus arteriosus/ Bulbus arteriosus = chamber after ventricle (muscular with valves = conus; elastic, no valves = bulbus ; embryonic = bulbis cordis)

Human Heart Development

Human Heart Development Sinus Venosus lost except some cells that become the sinoatrial node (“pacemaker”) Sinoatrial valve lost. Atrium divides into right and left. Atrioventricular valve divides to form (right) tricuspid and (left) bicuspid/mitral valves Ventricle divides into right and left.

Human Heart Development Bulbis cordis lost. Ventral aorta (truncus arteriosus) divides to become - (left) ascending aorta that will maintain connection to aortic arches III & IV and - (right) pulmonary trunk artery that will maintain connection to aortic arch VI.

Human Heart Blood Flow

Human Heart Blood Flow

Heart Chambers & Valves

Heart Position/Stethoscope

Comparative Heart

Blood Flow From Heart high oxygen low oxygen

Heart Chambers & Valves Teleost

Heart Chambers Sarcopterygiians = at least partially developed interatrial septum Tetrapods = complete interatrial septum Amniotes = conus arteriosus lost during devel; sinus venosus incorp. into right atrium; at least partially developed interventricular septum Mammals & Archosaurs = complete interventricular septum

Heart Chambers & Valves

Heart Chambers & Valves

Subphylum Vertebrata Chondrichthys Actinopterygii coelacanths amphibians hagfishes lungfishes lampreys Mammalia Reptilia bulbus arteriosus complete interatrial septum partial interatrial septum heart (sinus venosus, atrium, ventricle, conus arteriosus)

Amniota lizards & snakes crocodilians montremes marsupials eutherians turtles lizards & snakes crocodilians birds complete interventricular septum complete interventricular septum conus arteriosus lost in adult; incomplete interventricular septum; sinus venosus lost (in rt. atrium)

Gnathostome Heart Chambers Chondrichthys Actinopterygii lungfishes Sinus Venosus sinus venosus Atrium atrium atrium (partially l.-r. divided) Ventricle ventricle venticle Conus Arteriosus conus arteriosus bulbus arteriosus (not muscular)

Gnathostome Heart Chambers amphibians lizards turtles Sinus Venosus sinoatrial node (incorp. in rt. atrium) Atrium left atrium right atrium Ventricle ventricle ventricle (partial. left-right divided) Conus Arteriosus conus arteriosus lost

Gnathostome Heart Chambers crocodilians birds Mammalia Sinus Venosus sinoatrial node (incorp. in rt. atrium) Atrium left atrium right atrium Ventricle left ventricle right ventricle (connected by foramen of Panizza) Conus Arteriosus lost

Lymphatic System

Lymphatic System Plasma in capillaries is forced into the tissues by blood pressure. Edema = swelling of tissues due to accumulation of fluid (plasma/lymph). Usually, edema is avoided because… plasma in tissues diffuses into blind lymphatic capillaries and is called lymph.

Lymphatic System artery heart capillaries vein HIGH PRESSURE LOW PRESSURE

Lymphatic System Lymphangitis = inflamation of a lymph vessel. (ROOT WORDS) Lymphangitis of the vessel indicated by the arrow caused the edema in the middle finger.

Lymphatic System Lymph vessels = thin walled vessels with valves (similar in structure to veins, but with weak contractile ability); return lymph to venous system. Lymph nodes (lymphatic cisterns) = expanded lymph vessels filled with connective tissue and leukocytes. Immunological filters. Lacteals = lymph vessels in villi of the jejuno-ileum (small intestine) absorb fats.

Lymph Vessel

Lymph Node & Lg. Vessel (in mesentary proper)

Human Cephalic Lymph System

Human Lymphatic System

Lymphatic System Contractile lymph vessels exist in most vertebrates (Form localized Lymph Hearts in hagfishes, lungfishes, amphibians, turtles, liz. & snakes, & ostriches+related birds) Lacteals = lymph vessels in the intestinal villi – Only in TETRAPODS. Lymph nodes / sacs / cisterns = expanded lymph vessels filled with connective tissue and leukocytes. Only in AMNIOTES.

Human Lymphatic System

Subphylum Vertebrata Chondrichthys Actinopterygii coelacanths amphibians hagfishes lungfishes lampreys Mammalia Reptilia lymph nodes & cisterns lacteals

Respiratory System

General Respiratory Systems Ventilation = movement of air or water across a respiratory surface. Apnea = cessation of ventilation Unidirectional ventilation = air/water moves 1 direction over resp. surface Bidirectional ventilation = air/water moves 2 directions over resp. surface. (tidal) Concurrent & Counter current exchange

Concurrent Same Direction Current water or air blood from body (heart) to body

Counter Current Counter Current System water or air blood to body from body (heart)

Human Trachea & Lung Development

Human Respiratory System nasal cavity pharynx larynx trachea bronchus bronchiole alveolus in lung

Human Respiratory System

Human Larynx

Human Lungs

Human Ventilation

Comparative Respiration

Aquatic Respiratory Structures Skin is a significant respiratory surface in many NON-amniotes. Gills = aquatic pharyngeal respiratory surfaces. (Internal = within pharynx; External = protrude from pharynx) salamander (axolotl) reedfish lungfish

Internal Gills Chondrichthys Actinopterygii

Gills Gill = bony pharyngeal arch and two sets of filaments. Absent in Amniotes and adult Lissamphibians Each filament bears many lamellae (small, flat projections) & blood passes through capillaries in the lamellae. Blood movement through lamellae sets up a counter current system.

Gills

Counter Current

Gill Filament afferent lamella efferent

Lungs/Swimbladders Lung(s) = aerial gut diverticulum respiratory surface. (Osteichthys) In fishes called swimbladder & usually used for buoyancy as well. Pneumatic duct = Connection to digestive tract in Actinopterygii & Dipnoi. Trachea (in Tetrapods) is a pneumatic duct held open with cartilage rings.

Lungs/Swimbladders Respiratory lungs/swimbladders are often compartmentalized. Faveoli = non-mammal lung chambers. Alveoli = rounded mammal lung chambers.

Lungs/Swimbladders (Osteichthys) Ancestral lungs/swimbladders: Ventral trachea/pneumatic duct. Two “lungs” Swimbladder of non-reedfish actinopterygiians: Dorsal pneumatic duct. One lung dorsal to esophagus. (Pneumatic duct lost in some teleosts.)

Lungs/Swimbladders Actinopterygii lungfish Amia calva Polypterus carp salamander bass

Craniate Respiration Chondrichthys Actinopterygii coelacanths amphibians hagfishes lungfishes lampreys Mammalia Reptilia alveoli gill filaments lost trachea (with cartilage “rings”) lungs (swimbladder) respiratory gills with filaments

Class Actinopterygii sturgeons & paddlefish Amia calva bowfin TELEOSTS reedfishes TELEOSTS gars single dorsal lung with dorsal connection to digestive tract

Aerial Respiratory Modifications Ancestrally - amphibians & “fishes” - “Swallow” air – push into lungs - Elastic lungs recoil to push air out. Prehepatic diaphragm (mammals) - Negative pressure pulls air into lungs - Body cavity contraction pushes air out. Posthepatic diaphragm (crocodilians) - Liver pushes air out of lungs.

Ventilation “swallow” air prehepatic posthepatic

Bird Respiration Parabronchi (birds) = one-way, passageways through the lung faveoli. Lungs not very compressible. Air Sacs (birds) = membranous sacs for containing air (9 off of each lung) Air moved by expansion & contraction of air sacs. Countercurrent, constant flow of O2 rich air over capillaries even when exhaling.

Avian Lungs

Avian Inhalation

Avian Exhalation

Avian Respiration

Amniota lizards & snakes crocodilians monotremes marsupials eutherians turtles lizards & snakes crocodilians birds * air sacs; parabronchi prehepatic diaphragm * posthepatic diaphragm