Circulation and RespirationCirculation and Respiration

Gastrovascular SystemsGastrovascular Systems Body plan is only two or a few cell Body plan is only two or a few cell

layers thick.layers thick. Food enters the same opening as Food enters the same opening as

waste exits.waste exits. The fluid in the cavity of cnidarians is The fluid in the cavity of cnidarians is

continuous with that around them and continuous with that around them and Planarians have a branching cavity Planarians have a branching cavity that is adequate for their small thin that is adequate for their small thin (flat) bodies.(flat) bodies.

Larger animalsLarger animals Need to have a Circulatory system because Need to have a Circulatory system because

diffusion takes too long.diffusion takes too long. A system has blood, a heart/pump that A system has blood, a heart/pump that

generates blood pressure.generates blood pressure. Circulatory systems are powered by cellular Circulatory systems are powered by cellular

energyenergy Open systems – blood is not separated from Open systems – blood is not separated from

body fluid, it bathes the organs, this “blood” is body fluid, it bathes the organs, this “blood” is called hemolymph. Blood is pumped by the called hemolymph. Blood is pumped by the heart in to spaces called sinuses. It flows back heart in to spaces called sinuses. It flows back to the heart via a pressure gradientto the heart via a pressure gradient

Closed systemsClosed systems Blood is confined to vessels and Blood is confined to vessels and

maintained separate from the body maintained separate from the body fluid.fluid.

Cardiovascular systems consist of Cardiovascular systems consist of closed system with a heart the has closed system with a heart the has one or two ventricle and one or two one or two ventricle and one or two atriaatria

Cardiovascular SystemsCardiovascular Systems Atria – heart chambers that receive bloodAtria – heart chambers that receive blood Ventricles – heart chambers that pump bloodVentricles – heart chambers that pump blood Artery – vessel that carries blood away from the Artery – vessel that carries blood away from the

heart.heart. Arterioles – small vessels that carry blood to Arterioles – small vessels that carry blood to

the capillariesthe capillaries Capillaries(bed) thin walled vessel that infiltrate Capillaries(bed) thin walled vessel that infiltrate

the body, material exchange occurs here.the body, material exchange occurs here. Venules – small vessels that carry blood to Venules – small vessels that carry blood to

veinsveins Veins – carry blood to the heartVeins – carry blood to the heart

Pulmocutaneous circulationPulmocutaneous circulation Amphibians have vessels leading Amphibians have vessels leading

from the pulmonary arteries to the from the pulmonary arteries to the skin that receive deoxygenated blood skin that receive deoxygenated blood and allow the capillaries in the skin and allow the capillaries in the skin to remove carbon dioxide and even to remove carbon dioxide and even absorb some oxygen.absorb some oxygen.

Systemic and Pulmonary Systemic and Pulmonary CirculationCirculation

Systemic - Supplies nourishment and Systemic - Supplies nourishment and removes wastes from the tissue removes wastes from the tissue located throughout the bodylocated throughout the body

Pulmonary – blood vessels in the Pulmonary – blood vessels in the lungs flow to and from capillaries lungs flow to and from capillaries where oxygen is absorbed and where oxygen is absorbed and carbon dioxide is removed.carbon dioxide is removed.

Double Circulation Double Circulation (not found in (not found in fish)fish)

Blood flowing through the lungs is Blood flowing through the lungs is pumped separately from the blood pumped separately from the blood flowing to the body.flowing to the body.

Much stronger flow to the brain, Much stronger flow to the brain, muscles, ect.muscles, ect.

ECG or EKGECG or EKG Electrocardiogram measures the Electrocardiogram measures the

electrical currents that are electrical currents that are conducted in the body as the heart conducted in the body as the heart goes through the cardiac cyclegoes through the cardiac cycle

Movement of blood Movement of blood Adam Movement of blood overviewAdam Movement of blood overview Movement of oxygen and Carbon Movement of oxygen and Carbon

DioxideDioxide

capillariescapillaries Capillary functionCapillary function Pressure – fluid loss and regainPressure – fluid loss and regain

V. On outline - BloodV. On outline - Blood Blood cells and cell fragments occupy Blood cells and cell fragments occupy

about 45% of the blood volume.about 45% of the blood volume. 55% is plasma.55% is plasma. Plasma is 90% water, it contains Plasma is 90% water, it contains

electrolytes.electrolytes. Plasma proteins help to maintain pH, Plasma proteins help to maintain pH,

osmotic balance, and blood viscosity.osmotic balance, and blood viscosity. Some of these proteins are Some of these proteins are

immunoglobulins that function in defense.immunoglobulins that function in defense.

Cellular ElementsCellular Elements Blood plasma suspends 3 elements:Blood plasma suspends 3 elements: 1. RBC’s--oxygen transport, most 1. RBC’s--oxygen transport, most

numerous.(eurythrocytes)numerous.(eurythrocytes) 2. WBC’s--defense of body.2. WBC’s--defense of body.

(leukocytes)(leukocytes) 3. Platelets--fragments of cells 3. Platelets--fragments of cells

which help in the clotting process.which help in the clotting process.

EurythrocytesEurythrocytes Shape is related to its function.Shape is related to its function. Biconcave increases its surface Biconcave increases its surface

area.area. Small size and number increases Small size and number increases

surface area--related to function.surface area--related to function. Mammalian lack nuclei--allows for Mammalian lack nuclei--allows for

more hemoglobin.more hemoglobin.

LeukocytesLeukocytes These are white blood cells and there These are white blood cells and there

are 5 types:are 5 types: 1. Monocytes, Neutrophils, 1. Monocytes, Neutrophils,

Basophils, Eosinophils, LymphocytesBasophils, Eosinophils, Lymphocytes Collectively, these fight infection.Collectively, these fight infection. These spend most of their time in the These spend most of their time in the

interstitial fluid where they fight interstitial fluid where they fight invadersinvaders..

PlateletsPlatelets These plug wounds and prevent These plug wounds and prevent

blood loss.blood loss. Wounds release factors that Wounds release factors that

make platelets sticky and enable make platelets sticky and enable them to adhere to collagen fibers them to adhere to collagen fibers in connective tissue slowing in connective tissue slowing blood loss.blood loss.

Stem cellsStem cells In the marrow of some bones, In the marrow of some bones,

particularly the ribs, particularly the ribs, vertebrae, breastbone and vertebrae, breastbone and pelvis the blood cells are pelvis the blood cells are created from pluripotent cells created from pluripotent cells that can produce.that can produce.

Blood clottingBlood clotting Platelets plug wounds and Platelets plug wounds and

prevent blood loss.prevent blood loss. Wounds release factors that Wounds release factors that

make platelets sticky and enable make platelets sticky and enable them to adhere to collagen fibers them to adhere to collagen fibers in connective tissue slowing in connective tissue slowing blood loss.blood loss.

Respiratory SystemsRespiratory Systems Respiratory surfaces allow for the Respiratory surfaces allow for the

exchange of gases.exchange of gases. They are always thin and bathed in They are always thin and bathed in

water.water. In most animals, the respiratory In most animals, the respiratory

medium is a thin, moist epithelium.medium is a thin, moist epithelium. This separates the respiratory This separates the respiratory

medium from the blood.medium from the blood.

GillsGills Are out-foldings of the body Are out-foldings of the body

surface suspended in water.surface suspended in water. They are loaded with capillaries.They are loaded with capillaries. Animals with gills ventilate them Animals with gills ventilate them

which moves water with a high which moves water with a high concentration of Oconcentration of O22 over them. over them.

Tracheal SystemTracheal System Found in insects.Found in insects. It is made up of tubes that branch It is made up of tubes that branch

through the body which is a variation through the body which is a variation on a folded, internal respiratory on a folded, internal respiratory surface.surface.

The trachea branches smaller and The trachea branches smaller and smaller and contacts nearly every cell.smaller and contacts nearly every cell.

LungsLungs These are respiratory organs found These are respiratory organs found

in one spot of the body.in one spot of the body. They have a dense net of capillaries They have a dense net of capillaries

immediately below the epithelium immediately below the epithelium on the respiratory surface.on the respiratory surface.

They are connected to a closed They are connected to a closed system that transports gases to and system that transports gases to and from other regions of the body.from other regions of the body.

Ventilating the lungsVentilating the lungs Positive pressure breathing-amphibiansPositive pressure breathing-amphibians Negative pressure breathing-humansNegative pressure breathing-humans Diaphragm – muscle below rib cageDiaphragm – muscle below rib cage Tidal volume is the volume of air inhaled Tidal volume is the volume of air inhaled

with each breath.with each breath. Max. during forced breathing is 3-4.8LMax. during forced breathing is 3-4.8L

Residual volume is the amount remaining Residual volume is the amount remaining in the lungs after a forced exhale.in the lungs after a forced exhale.

Vital capacityVital capacity maximum volume of air that a maximum volume of air that a

person can person can exhaleexhale after maximum after maximum inhalationinhalation. It can also be the . It can also be the maximum volume of air that a maximum volume of air that a person can inhale after maximum person can inhale after maximum exhalation. exhalation.

Control centers in the brainControl centers in the brain Human breathing is mostly under Human breathing is mostly under

autonomic control.autonomic control. 2 regions of the brain control this:2 regions of the brain control this:

The pons and the medulla.The pons and the medulla. The pons controls the medulla The pons controls the medulla

which sets a basic breathing which sets a basic breathing rhythm.rhythm.

Sensors in the aorta and carotid Sensors in the aorta and carotid arteries exert secondary control arteries exert secondary control over breathing.over breathing.

These sensors monitor OThese sensors monitor O22, CO, CO22 and and blood pH.blood pH.

The pH is largely controlled by COThe pH is largely controlled by CO22 levels.levels.

GasesGases When COWhen CO22 levels increase, levels increase,

carbonic acid levels increase carbonic acid levels increase lowering the blood pH.lowering the blood pH.

When pH drops, the depth and When pH drops, the depth and rate of breathing increases rate of breathing increases helping to remove excess COhelping to remove excess CO22..

OO22 levels only have an effect on levels only have an effect on breathing rate at high altitudes.breathing rate at high altitudes.

More Carbon DioxideMore Carbon Dioxide In addition to transporting OIn addition to transporting O22, hemoglobin , hemoglobin

helps transport COhelps transport CO22 and assists in buffering. and assists in buffering. Respiring cells produce CORespiring cells produce CO22. Carbonic . Carbonic

anhydrase catalyzes the reaction of COanhydrase catalyzes the reaction of CO22 with Hwith H22O to form HO to form H22COCO33..

HH22COCO33 dissociates into H dissociates into H++ + HCO + HCO33--

Most of the HMost of the H++ attaches to hemoglobin and attaches to hemoglobin and other proteins minimizing the change in other proteins minimizing the change in blood pH. blood pH.

Diffusion in the AlveoliDiffusion in the Alveoli

O2

CO2

Air In & Out

Alveolus

OxygenatedBlood

Deoxygenated Blood

BloodCapillary

Body Cells

CO2

O2

BloodCapillary

TissueFluid

Gas Exchange at the CellsGas Exchange at the Cells