Download Circulatory System 63. Circulatory System

Circulatory System
63. Circulatory System
• Transports substances throughout
the body
A. Substances transported
a. Oxygen from lungs
b. Nutrients absorbed by small
intestines
c. Antibodies that fight disease
d. Hormones
e. Wastes – CO₂, nitrogenous wastes
Circulatory System
• Made up of three main parts:
Blood
Vessels
Heart
Blood
64. Blood Vessels
• Tubes that circulate blood through
the body
A. Closed System
• Blood is contained in heart or blood
vessels at all times
B. Length
• If stacked end to end, could stretch
60,000 miles
3 types of blood vessels
Arteries
Capillaries
Veins
D. Arteries
• Large, muscular
vessels, carry
blood away from
the heart
a. 3 Layers
• Inner endothelium
3 Layers
• Middle layer of smooth muscle
Vasoconstriction
• Muscles contract, vessel diameter
decreases
Vasodialation
• Muscles relax, vessel diameter
increases
3 Layers
• Outer connective tissue
Main Arteries
Largest artery
b. Aorta
Atherosclerosis
c. Disease where plaque builds up
along the walls of arteries
Arterioles
d. Smallest branches of the arteries,
connect to capillaries
E. Capillaries
• Smallest blood vessels, only simple
epithelial layer for exchange to occur
Many are so small that blood
flows through in a single line
Capillaries
Capillary Bed
a. Interweaving networks of capillaries
Venules
b. Small tubes where capillaries unite
to connect to the veins
F. Veins
• Large vessels that
carry blood to the
heart
a. 3 layers – thinner, less muscle
Largest Vein
b. Superior and Inferior Vena Cava
Valves
c. One way, prevent
backflow
Varicose Veins
d. Incompetent valves allow the blood
to flow back
Varicose Veins
Pathway
HAacvVH
The Heart
65. Heart
• Muscular organ that pumps blood
through the body
About the size of a fist
Slightly tilted to the left
A. Chambers - 4
a. Upper – left and right Atria
• Right-receives de-oxygenated blood
from body
• Left- receives oxygenated blood from
lungs
b. Lower – left and right Ventricle
• Right - pumps blood into lungs
• Left - pumps blood to the body
B. Valves - 4
a. Diastole – Heart relaxes, pulls blood
in
Tricuspid valve
• regulates blood flow between Right
Atrium (RA) and Right Ventricle (RV)
Mitral Valve
• lets O₂ rich blood from your lungs
pass from LA to LV
b. Systole – Heart contracts,
pushes blood out
Pulmonary valve
• Controls blood flow from RV to
pulmonary arteries to lungs for O₂
Aortic valve
• Opens way for O₂ rich blood to pass
from LV into aorta
C. Double Pump
• pumps oxygenated & deoxygenated
blood
a. Pulmonary circuit – sends O₂ poor
blood to lungs
b. Systemic circuit – sends O₂ rich
blood to body
Path of Blood Through the Heart
Path of Blood Through the Heart
a. Superior and inferior vena cava
Path of Blood Through the Heart
b. Right atrium
Path of Blood Through the Heart
c. Tricuspid Valve
Path of Blood Through the Heart
d. Right ventricle
Path of Blood Through the Heart
e. Pulmonary Valve
Path of Blood Through the Heart
f. Pulmonary arteries
Path of Blood Through the Heart
g. Lungs
Path of Blood Through the Heart
h. Pulmonary veins
Path of Blood Through the Heart
i. Left atrium
Path of Blood Through the Heart
j. Mitral Valve
Path of Blood Through the Heart
k. Left ventricle
Path of Blood Through the Heart
l. Aortic Valve
Path of Blood Through the Heart
m. Aorta
E. Septum
• Wall that separates the ventricles
Keeps oxygenated
blood and
deoxygenated blood
from mixing
“Blue Baby”
a. Hole in septum allows oxygenated
and deoxygenated blood to mix
F. Heart Rate
• Number of times the heart beats per
minute
Males – 70 bpm
Females – 75 bpm
newborn-130
3 months-150
1 year- 125
3 years- 100
12 years- 85
adult- 60-101
“Lub-dup”
• Lub – valves between atria and
ventricles closing
• Dup – valves between ventricles and
blood vessels closing
Heart Murmur
• Abnormal heart sounds
Can be from:
Thin walls that vibrate
Increased blood flow
Valve problems