Circulatory and Respiratory Systems

Class Quiz Tom. Popcorn – pathway of blood through systemic and pulmonary systems Start at RIGHT ATRIUM and end at RIGHT ATRIUM

Word list – you put it in the correct order Right atrium Left atrium Right ventricle Left ventricle Pulmonary arteries Pulmonary veins Pulmonary trunk Aorta Capillaries of lungs Capillaries of body Superior and inferior vena cava

Heart: external

Heart: internal AV valve AV valve

Cardiac Cycle Diastole = relax Systole = contract See chart on 620

Structure and Function Atria are composed of thinner cardiac muscles and their contractions are quick and not nearly as forceful as ventricular contractions (0.1 sec) Ventricles are composed of thicker cardiac muscle and much more forceful then atrial contractions, the contractions also last longer (0.3 sec)

Pulse – used to determine heart rate (beats per min Pulse – used to determine heart rate (beats per min.), pulse is actually the rhythmic stretching of arteries caused by the pressure of blood flow due to the powerful contractions of the ventricles

Cardiac Output Cardiac output = volume of blood per minute into the systemic loop - depends upon… heart rate (specifically left ventricle rate of contraction) and stroke volume – volume of blood pumped out of left ventricle with each contraction

Why is cardiac output important? HINT: Av. Person at rest = 5.25 L/min which is about equivalent to total volume of blood in body Av. person who has decided to exercise = 20.75 L/min

Why would the cardiac output increase with exercise?

Why is exercise good for the heart?

Increase efficiency of heart – increase in stroke volume

Rhythmic Beating of the Heart Individual cells of cardiac tissue beat on their own

Coordinating the “beat” SA (sinoatrial) node – aka pace maker Electrocardiogram (EKG or ECG) – reads the electrical currents produced during the heart beat

USE Figure 34.7 What do the following ECG recordings correspond to in regards to the action of the heart: P wave – QRS – T –

Blood Pressure Top # = systolic pressure Bottom # = diastolic pressure 120/80 Top # = systolic pressure Bottom # = diastolic pressure

Vessel types

Blood Vessel System Law of continuity – think water hose and water pressure Water flow velocity depends upon diameter the “pipe” in this case the vessel So… which should have a faster blood flow arteriole or capillaries?

Yes, a single capillary is smaller in diameter than an arteriole BUT… You must take into account the total cross sectional diameter of an entire capillary bed – which consists of lots of individual capillaries – making the total diameter much greater than the arteriole

So… Blood travels very slowly in a capillary to allow for exchange of substances, also capillary walls are thin enough to allow for this

Lymphatic system

What is the role of each?

Respiratory system

Lungs

Lungs: internal

Inhaling and exhaling- again with the physics and chemistry

Boyle’s law and breathing Volume and pressure are inversely proportional – mark this with arrows in your notes! See the balloon model ADAM

Partial pressures and the unloading and loading of respiratory gases Gases (like all molecules) will move from an area of high partial pressure to lower partial pressure

Focus on Oxygen Hemoglobin – found in RBCs

Oxygen Hemoglobin (contains iron) and binds up to 4 molecules of oxygen Affinity changes as oxygen molecules bind or release, One oxygen attaching causes hemoglobin to have a greater affinity for even more oxygen – how? http://en.wikipedia.org/wiki/Hemoglobin#Binding_of_ligands An oxygen released causes hemoglobin to release even more

pH levels affect hemoglobin affinity for oxygen also when CO2 levels are high, this causes blood pH to lower and a greater release of oxygen CO2 + H2O --- HCO3- + H+

Oxygen Disassociation Curves

Oxygen Disassociation Curves

Carbon dioxide focus: tissue to blood STEPS:

Carbon dioxide: blood to lungs STEPS:

Explain this