Circulatory System Flashcards
The transport system of the body
Circulatory system
3 Components of Circulatory System
- Heart
- Blood vessels
- Blood
Heart separates the pulmonary and systemic circulations and ensures the flow and supply of oxygen-rich blood to tissues.
Routing blood
Left side of the heart pumps blood to all other tissues of the body and back to the right side of the heart
Systemic circulation
Right side of the heart pumps oxygen-poor blood to the lungs and back to the left side of the heart
Pulmonary circulation
Contraction of the heart generates blood pressure that forces blood through the blood vessels
Generation of blood pressure
The human heart has its own cavity. What cavity is it?
pericardial cavity
The left and right atria are separated by the
atrial septum
The heart consists of 4 chambers.
> Left and right Atrium
Left and right Ventricle
Left and right ventricles are separated by the
ventricular septum
The right atrium and right ventricle are separated by the
Tricuspid valve
The left atrium and left ventricle is separated by
Mitral valve
Blood flow to the pulmonary arteries from the right ventricle is also guarded by the?
pulmonary semilunar valve
In the same manner, blood flow to the ascending aorta from the left ventricle is guarded by the?
aortic semilunar valve.
blood flows away from the heart; 3 cell layers, thick-walled.
Arteries
blood flows towards the heart; valves prevent backflow due to low blood pressure; 3 cell layers, thin-walled.
Veins
connect arterioles to venules; the site of capillaries/tissues is where **nutrient/waste **exchange by diffusion takes place; 1 cell layer
Capillaries
A blood vessels that can change along their length from elastic to muscular to microscopic
Arteries
Receives blood from the the heart
Large arteries/ Aorta
Guides blood direction
Medium-sized arteries/ Coronary arteries
Regulate blood flow
Microscopic arteries/ arterioles
A blood vessels that can change size from large to medium to venules
Veins
A very small veins that collect blood from capillaries
Venules
A type of veins that have thin tunica media and few smooth muscle cells ; tunica externa with longitudinal bundles of elastic fibers.
Medium sized veins
A type of veins that have all 3 tunica layers, thick tunica externa and thin tunica media
Large veins
The smallest and most numerous of the blood vessels, form the connection between the vessels
Capillaries
Capillary distribution varies with what activity?
Metabolic Activity of body
tissues
A connective tissue consisting of plasma and formed elements
Blood
erythrocytes
Red blood cells (RBCs)
leukocytes
White blood cells (WBCs)
It is composed of liquid plasma and formed elements
Blood
Blood accounts for approximately how many percentage of our weight?
8%
Pale yellow fluid containing over 100 solutes
Plasma
Helps maintain osmotic pressure
Albumin
38% of the plasma proteins
Globulins
antibodies and complement
Immunity
Mostly water (91%), Contains proteins (7%)
Plasma
bind to molecules such as hormones
Transport
Converted to fibrin during clot formation
Fibrinogen
Just cell fragments most formed elements survive in the bloodstream for only a few days
Platelets
Biconcave discs, anucleate, essentially no organelles.
RBCs
What protein our RBCs contains that functions in gas transport?
hemoglobin (Hb)
Accounts for about a third of the cell’s volume
Hemoglobin
Each heme group bears an atom of?
Iron
A molecules in hemoglobin that transport oxygen
Heme
Oxygen content determines blood color
Oxygenated: bright red.
Deoxygenated: darker red.
Globin molecules transport
carbon dioxide
The life span of an erythrocyte is
100–120 days
Heme becomes ________that is secreted in bile.
bilirubin
Make up 1% of the total blood volume
WBC
contain large cytoplasmic granules
granulocytes
very small granules that cannot be
easily seen with the light microscope
agranulocytes
Only blood components that are complete cells. Can leave capillaries via ameboid movement and move through tissue spaces.
WBC
neutrophils, eosinophils, and basophils
Granulocytes
Most common type of WBC. Our body’s bacteria slayers
Neutrophils
Account for 0.5% of WBCs
Basophils
inflammatory chemical that acts as a vasodilator and attracts other
WBCs (antihistamines counter this effect)
Histamine
prevents the formation of clots
Heparin
Have red-staining, bi-lobed nuclei connected via a broad band of nuclear material and account for 1–4% of WBCs
Eosinophils
lymphocytes and monocytes.
Lack visible cytoplasmic granules
Agranulocytes
Account for 25% or more of WBCs. Are found mostly enmeshed in
lymphoid tissue (some circulate in the blood)
Lymphocytes
There are two types of lymphocytes:
T cells
B cells
Stimulated by bacteria or toxins. Give rise to plasma cells, which
produce antibodies.
B cells
Protect against viruses and other intracellular microorganisms.
Attack and destroy the cells that are infected.
T cells
Account for 4–8% of leukocytes.
They are the largest leukocytes
Monocytes
Function in clotting
Platelets
Seal holes in small vessels
Formation of platelet plugs
Help seal off larger wounds in the vessels.
Formation of clots
RBC membranes have glycoprotein antigens on their external
surfaces.
Blood Groupings
Acts as a solvent and suspending medium for blood components
Water
Maintain osmotic pressure (albumin), destroy foreign substances (antibodies and complement), transport molecules (albumin and globulins), and form clots (fibrinogen)
Proteins
Involved in osmotic pressure (sodium and chloride ions), membrane potentials (sodium and potassium ions), and acid-base balance (hydrogen, hydroxide, and bicarbonate ions)
Ions
Source of energy and “building blocks” of more complex molecules (glucose, amino acids, triglycerides)
Nutrients
Involved in aerobic respiration
Gases
Breakdown products of protein metabolism (urea and ammonia salts) and red blood cells (bilirubin)
Waste products
Catalyze chemical reactions (enzymes) and stimulate or inhibit many body functions (hormones)
Regulatory substances
