Chapter 42.4 Flashcards
With open circulation, what is the fluid continuous with
the fluid surrounding all body cells
What do the closed circulatory systems of vertebrates contain
a more highly specialized fluid called blood
Plasma
a liquid matrix
What is blood in vertebrates?
a connective tissue consisting of several kinds of cells suspended in plasma
What percent of the volume on blood do cellular elements occupy
45%
What does plasma contain?
inorganic salts as dissolved ions, sometimes called electrolytes
what do plasma proteins influence
blood pH
What do plasma proteins help maintain
osmotic balance between blood and interstitial fluid
What do particular plasma proteins function in
lipid transport, immunity, and blood clotting
What is plasma similar in composition to
interstitial fluid; but plasma has a much higher protein concentration
Suspended in blood plasma are two types of cells
- Red blood cells (erythrocytes)
2. White blood cells (leukocytes)
Red blood cells
transport O2
White blood cells
function in defense
Platelets
fragments of cells that are involved in clotting
fragments of cells that are involved in clotting
platelets
The most numerous blood cells
red blood cells (erythrocytes)
What do red blood cells contain
hemoglobin
hemoglobin
the iron-containing protein that transports O2
the iron-containing protein that transports O2
hemoglobin
What does each molecule of hemoglobin do
binds up to four molecules of O2
In mammals, what do mature erythroctes lack
a nuclei and mitochondria
What is sickle-cell disease caused by
abnormal hemoglobin proteins that form aggregates
What do the aggregates do
deform an erythrocyte into a sickle shape
What can sickle cells do
rupture or block blood vessels
Five major types of white blood cells (leukocytes)
- monocytes
- neutrophils
- basophils
- eosinophils
- lmphocytes
How do white blood cells function in defense
either by
- phagocytizing bacteria and debris
- mounting immune responses against foreign substances
Where are leukocytes found
both in and outside of the circulatory system
What are platelets
fragments of cells that function in blood clotting
What do erythrocytes, leukocytes, and platelets all develope from
a common source of stem cells in the red marrow of the bones, especially ribs, vertebrae, sternum, and pelvis
The hormone erythropoietin (EPO)
stimulates erythrocyte production when O2 delivery is low
stimulates erythrocyte production when O2 delivery is low
erythropoietin (EPO)
What can physicians use recombinant EPO to treat
anemia
What is coagulation
the formation of a solid clot from liquid blood
the formation of a solid clot from liquid blood
coagulation
what does a cascade of complex reactions do
convert inactive fibrinogen to fibrin (forming a clot)
A blood clot formed within a blood vessel
thrombus
thrombus
a blood clot formed within a blood vessel
what can a thrombus do
block blood flow
Cardiovascular diseases
disorders of the heart and the blood vessels
What is the range of cardiovascular diseases
minor disturbances of vein or heart function to life-threatening disruptions of blood flow to the heart of brain
A type of cardiovascular disease caused by the buildup of fatty deposits (plaque) within arteries
atherosclerosis
what is atherosclerosis caused by
the buildup of fatty deposits (plaque) within arteries
what is a key player in the development of atherosclerosis
cholesterol
Low-density lipoprotein (LDL)
delivers cholesterol to cells for membrane production
High-density lipoprotein (HDL)
scavenges excess cholesterol for return to the liver
What does risk for heart disease increase with
a high LDL to HDL ratio
What is also a factor in cardiovascular disease
inflammation
What is a heart attack (mocardial infarction)
the damage or death of cardiac muscle tissue resulting from blockage of one or more coronary arteries
What is a stroke
the death of nervous tissue in the brain, usually resulting from rupture or blockage of arteries in the head
What is angina pectoris
chest pain caused by partial blockage of the coronary arteries
A high LDL/HDL ratio…
increases the risk of cardiovascular disease
What can the proportion of LDL relative to HDL be decreased by
exercise and avoiding smoking and foods with trans fats
what do drugs called statins reduce
LDL levels and risk of heart attacks
What plays a role in atherosclerosis and thrombus formation
inflammation
What does aspirin inhibit
inflammation
What does aspirin reduce
the risk of heart attacks and stroke
Hypertension (high blood pressure)
contributes to heart attack and stroke, as well as other health problems
What can hypertension be controlled by
dietary changes, exercise, and/or medication
