Pulmonary Circulation
Between the heart and the lungs
Oxygenated blood coming from lungs travels to the left side of the heart
Deoxygenated blood (CO2 rich blood) from the right side of the heart will be pumped back to the lungs
Systemic Circulation
Between the heart and the body
Right side of the heart receives deoxygenated blood from the body
Left side of the heart pumps oxygenated blood to the body
Atria
are the top/collecting chambers of the heart
have thinner walls
Ventricles
are the bottom/pumping chambers of the heart
have thicker/muscular walls
Pulmonary Arteries
carry
deoxygenated
blood AWAY from the right side of the heart towards the lungs
Pulmonary Veins
carry
oxygenated
blood to the left side of the heart from the lungs
Arteries
Carry blood
AWAY
from the heart
Most
carry
OXYGENATED (RED)
Blood (Except pulmonary artery going to lungs)
Branch into smaller arteries called
ARTERIOLES
Blood is under
HIGHEST PRESSURE
(from heart) &
PULSES
Have
Thick outer walls
made of collagen & elast
Arterioles
Smaller Arteries
Lumen
Inner space
Capillaries
Smallest blood vessels -
microscopic
Lumen is 10 um - only one RBC can fit through
Blood slows
down as it travels through- b/c of more space for blood volume to travel- allows time for exchange
The walls are only
One-cell thin
- so molecules can diffuse a
Veins
Carry blood
TOWARD
the heart
Most
carry
DEOXYGENATED
blood (blue) - except Pulmonary Veins coming from lungs
Small veins are called
VENUOLES
- Venuoles combine to form larger veins
Blood is under
LOWEST pressure
Thinner walls
than arteries and
less elasti
Skeletal Muscles
Helps keep blood flowing in a vein - needed b/c of low pressure
One-Way Valves
Veins have to keep blood from flowing backwards - needed b/c of low pressure
Venuoles
Small veins
Oxygenated Blood
Beginning of the SYSTEMIC circuit (leaving heart to the body)
End of the PULMONARY Circuit (returning to heart from lungs)
Deoxygenated Blood
Beginning of the PULMONARY circuit (leaving heart going to lungs)
End of SYSTEMIC circuit (returning to heart from the body tissues)
Blood Pressure
Arteries leaving the heart are under the highest pressure & Pulses with the heart contractions
Blood pulses in arteries (not veins)
Blood Pressure readings are taken in an artery in the upper arm
Blood flow in Heart
Body cells -> Inferior and superior Vena cava -> Right atrium -> right AV valve -> right ventricle -> right semilunar valve -> pulmonary arteries -> lungs -> pulmonary veins -> left atrium -> left AV valve -> left ventricle -> left semilunar valve -> aort
Cardiac Cycle
Diastole- when the chambers (atria and ventricles) are filling with blood, they are relaxed (normal diastole is 80mmHg)
The AV valves are open but the SL valves are closed
When the heart contracts there is an increase in pressure on the blood in the chamb
Disatole
when the chambers (atria and ventricles) are filling with blood, they are relaxed (normal is 80mmHg)
Systole
When the heart contracts there is an increase in pressure on the blood in the chamber causing the blood to leave through the semilunar valves (normal is 120mmHg)
Lub-dub
Heart sounds are associated with closing of heart valves
First sound
occurs as AV valves close and signifies beginning of systole (contraction)
Second sound
occurs when SL valves close at the beginning of ventricular diastole (relaxation)
Lub
Both Atria fill with blood
Both Atria contract at same time
Blood moves into ventricles through the AV valves
Valves "slam shut
Dub
Both ventricles contract at same time
Blood moves into the aorta & pulmonary artery through the Semi-lunar valves
Valves "slam shut
Cardiac Muscle
considered
myogenic
since it can initiate contraction without neural stimulation
SA Node
considered
the pacemaker
and
begins each heart beat by stimulating the atria to contract
Medulla
initiates changes in our heart rate when necessary
Sympathetic Nerve
(accelerator) increases heart rate
Parasympathetic Nerve
(decelerator) decreases heart rate
Adrenaline
During periods of stress and increased activity, adrenal glands secrete this, which increases heart rate by acting on the SA node
Plasma
Pale yellow liquid
50-60% of blood
All cells are suspended in it
Erythrocytes (Red Blood Cells)
Full of Hemoglobin to carry O2
Leucocytes (White Blood Cells)
Immune system
Fight disease (bacteria, viruses, fungal infections, etc.)
Platelets
Blood clotting
Functions of Blood
Carries dissolved materials to all cells
Fights infectious disease
Nutrients
glucose, amino acids, vitamins/minerals absorbed by small intestine
Oxygen
needed for cellular respiration
CO2 (Carbon Dioxide)
waste product of cellular respiration
Urea
waste product from the breakdown of amino acids; toxic and removed by the kidneys (part of urine)
Hormones
from glands to target cells
Antibodies
produced by leukocytes to fight infection
Heat
maintain homeostasis of body temperature (98.6degF)
Atherosclerosis
the slow buildup of plaque, which is composed of lipids, cholesterol, cell debris, and calcium
as plaque builds up it causes the arteries to become harder and less flexible preventing them from transporting blood efficiently
Coronary arteries
The heart has 3 of these that supply the heart with oxygen
Stenosis
If atherosclerosis leads to this (a significant blockage) in one of these arteries the heart muscle cells can be deprived of oxygen
Coronary Thrombosis
When a coronary artery or any main artery is fully blocked it can cause this (a heart attack)
Risks of Coronary Thrombosis
Factors that cant be controlled:
Age, heredity, race, gender
Factors that can be controlled:
High cholesterol
Smoking
High blood pressure
Stress
Diabetes
Obesity/lazy lifestyle
Pathogen
A disease causing agent
Can be living (bacteria, worm, protist, fungus) or non-living (virus)
Most are VIRUS or BACTERIA
Elephantiasis
pathogenic worms block lymphatic vessels -- causes severe edema (swelling)
Skin
Waterproof barrier of
dead
cells
Secretions repel bacteria
"Healthy" normal bacteria "out-compete" bad bacteria
Stomach acid
HCL kills bacteria in stomach
Mucous Membranes
Trap pathogens (sticky)
Have Lysosome enzyme to kill pathogens
Sometimes paired with cilia to "sweep" pathogens out (respiratory system)
Found in respiratory, urinary, reproductive and intestinal tracts
Secretions
Tears, mucous, and saliva have Lysosome enzyme to kill bacteria
Flushing Out
Urination, diarrhea, vomiting
Blood Clotting
Platlets & plasma form a "plug" to prevent pathogen entry into