Chapter 18:
The Circulatory System
Pages 492 – 513
Date
Cardiovascular System (pg. 492 - 493)
1. Your cardio system transport materials
through your bloodstream
2. Cardio system includes heart, blood, &
miles of blood vessels
3. Materials enter cells using _______.
4. Heart has 4 chambers: 2 atria (upper) &
2 ventricles (lower)
1. Atria pump 2 ventricles & ventricles pump to
the body
Circulation (pg. 494 – 495)
1. Pulmonary = blood flow from heart 2 lungs &
back
2. Systemic = blood flow to your body
3. Coronary = blood flow around the heart
4. Blood flow  Low O2 blood into right A, which
pumps into right V. Right V pumps 2 lungs 2 get
O2, then into left A. Left A pumps to left , which
pumps 2 body. Blood distributes O2, collects
CO2, & travels back to right A.
Vessels & Pressure (pg. 496 – 499)
1. Arteries = move blood away from heart
2. Veins = move blood 2 the heart
3. Capillaries = microscopic vessels that connect
arteries & veins; only 1 cell thick
4. Blood pressure = the force that blood exerts on
vessels walls as it moves through
1. Highest in arteries, then cap, then veins
2. Two numbers: 110/80  1st # is force from
ventricles; 2nd # is force of ventricles filling up
Cardiovascular Disease (pg. 500)
1. Heart disease is the leading cause of
death in the U.S.
2. Atherosclerosis = condition, fatty
deposits on artery walls
1. Fat builds up & blocks blood flow
3. Hypertension = high blood pressure
1. Atherosclerosis can cause hypertension
Blood (pg. 502)
1. Blood = a tissue made of cells, cell
fragments, & liquid
2. Functions: 1) carries O2 & removes
CO2; 2) carries wastes 2 kidneys 2 B
removed; 3) transports nutrients; 4)
contains materials 2 fight infections
3. Ur blood can fill five 1 liter bottles!
Parts of Blood (pg. 502 – 505)
1. Plasma = liquid part of blood & consists
mostly of water; it makes up more than half
of blood
1. Nutrients, minerals, & O2 are dissolved in
plasma
2. Hemoglobin = a chemical that carries O2 &
CO2
3. Red blood cells last about 120 days
4. White blood cells = fight infections,
bacteria, viruses that invade your body
5. Platelets = cell fragments that help clot
blood
1.
Work to stop bleeding & form scabs
6. For every millimeter of blood there are 5
million red blood cells, 400,000 platelets, &
7,000 white blood cells
Blood Types (pg. 505 – 507)
1. If someone gets the wrong blood type, their blood will clot,
block vessels, & die
2. Four blood types: A, B, AB, O ABO ID systems
1. Each type has a marker 2 ID it = antigen
2. Antibodies = proteins that destroy pathogens
1. U have the opp. blood antibodies as your blood type
3. Rh factor = another marker for blood
1. Having the factor = Rh positive
2. Not having the factor = Rh negative
Lymphatic System (pg. 511)
1. Fluid sometimes moves out of blood
2. Lymphatic system = collects fluid from body tissue
spaces & returns it to blood through lymph vessels
1. Also contains cells 2 help defend against
pathogens
3. Lymph = mostly water, dissolved nutrients, &
lymphocytes = type of white blood cell
4. There is no organ pumping lymph, when your
muscles contract, lymph is pushed around
Nodes & Organs (pg. 512 – 513)
1. Before lymph enters blood, it passes through
lymph nodes = which filter out microorganisms &
foreign materials engulfed by lymphocytes
2. When U R sick, lymphocytes gather pathogens &
drop them in nodes, which makes them swell
3. Lymph organs:
1. Tonsils – help protect nose & mouth
2. Thymus – produces lymphocytes
3. Spleen – helps filter blood, damaged/old blood
cells R broken down, destroy bacteria
Diseases (pg. 513)
1. Human immunodeficiency virus =
attacks helper T cells (type of
lymphocyte)
2. Helper T cells help produce
antibodies 2 fight infections
3. If too many T cells are attacked, the
disease progresses to acquired
immune deficiency syndrome