Circulatory and Circulatory and Respiratory SystemsRespiratory Systems

Chapter 37Chapter 37

Circulatory SystemCirculatory System

Transports oxygen, Transports oxygen, nutrients, and nutrients, and hormones throughout hormones throughout bodybody

Removes waste Removes waste products from cellsproducts from cells– COCO22, urea, urea

The HeartThe Heart

Four ChambersFour Chambers– Left and Right AtriaLeft and Right Atria

• Receive bloodReceive blood

– Left and Right VentriclesLeft and Right Ventricles• Pump blood outPump blood out

Septum divides left and right Septum divides left and right sidessides

Left side – oxygenated bloodLeft side – oxygenated blood Right side – deoxygenated bloodRight side – deoxygenated blood

CirculationCirculation

PulmonaryPulmonary– Right Vent.Right Vent.Pulmonary Pulmonary

ArteriesArteriesLungsLungsPulmonary Pulmonary VeinsVeinsLeft AtriumLeft Atrium

SystemicSystemic– Left Vent.Left Vent.AortaAortaBodyBodyVena Vena

CavaCavaRight AtriumRight Atrium

CirculationCirculation

HeartbeatHeartbeat

Controlled by the Controlled by the pacemaker (sinoatrial pacemaker (sinoatrial node)node)

Atria contract first, Atria contract first, ventricles contract secondventricles contract second

Blood VesselsBlood Vessels

Arteries – away from heartArteries – away from heart– Have smooth muscle in wallsHave smooth muscle in walls– Ventricles push blood throughVentricles push blood through

Capillaries – nutrient/waste Capillaries – nutrient/waste exchangeexchange– RBC must line up single file to fitRBC must line up single file to fit

Veins – to the heartVeins – to the heart– Have valves to prevent backflowHave valves to prevent backflow– Skeletal muscles push blood Skeletal muscles push blood

throughthrough

Blood VesselsBlood Vessels

BloodBlood

Plasma – liquid, 55% of Plasma – liquid, 55% of volumevolume– Carries dissolved nutrients, Carries dissolved nutrients,

hormones and wasteshormones and wastesErythrocytes (RBC)Erythrocytes (RBC)

– Made in red bone marrowMade in red bone marrow– No organellesNo organelles– Full of Full of hemoglobinhemoglobin

•Binds OBinds O22 in lungs in lungs

BloodBlood

Leukocytes (WBC)Leukocytes (WBC)– Made in red bone marrowMade in red bone marrow– Have organellesHave organelles– No hemoglobinNo hemoglobin– Attack foreign substances or Attack foreign substances or

organismsorganismsPlatelets – cell fragmentsPlatelets – cell fragments

– Create blood clotsCreate blood clots

BloodBloodRed Blood Cell

White Blood Cell

Platelets

Lymphatic SystemLymphatic System

Lymph vessels Lymph vessels collect excess collect excess fluid from fluid from tissues and tissues and return it to the return it to the blood (3L/day)blood (3L/day)

Lymph nodes Lymph nodes filter lymph filter lymph fluid for fluid for bacteriabacteria– Swollen glandsSwollen glands

Respiratory SystemRespiratory System

Path of inhaled air:Path of inhaled air:– Nose/sinusesNose/sinuses– Pharynx – where trachea and Pharynx – where trachea and

esophagus are one pipeesophagus are one pipe– Larynx – voice boxLarynx – voice box– Trachea – cartilage ringed Trachea – cartilage ringed

windpipewindpipe– Bronchi – one to each lungBronchi – one to each lung– Alveoli – tiny air sacs in lungsAlveoli – tiny air sacs in lungs

Respiratory Respiratory SystemSystem

Gas ExchangeGas Exchange

350 million alveoli350 million alveoliAlveoli are surrounded by Alveoli are surrounded by

capillariescapillariesOO22 diffuses into blood, CO diffuses into blood, CO22

into alveoliinto alveoliHemoglobin binds OHemoglobin binds O22

BreathingBreathing

Diaphragm Diaphragm contracts = contracts = inhaleinhale

Diaphragm Diaphragm relaxes = relaxes = exhaleexhale

Control of BreathingControl of Breathing

COCO2 2 in blood becomes in blood becomes carbonic acidcarbonic acid– Lowers the pH of bloodLowers the pH of blood– Triggers receptor neurons in Triggers receptor neurons in

brainbrain– Tells diaphragm to contract Tells diaphragm to contract

harderharderBreathing is controlled by Breathing is controlled by

COCO22 levels, not levels, not OO22 levels levels