Scheduled maintenance: Saturday, March 6 from 3–4 PM PST
Upgrade to remove ads
Only $2.99/month

7th Grade Science: Circulatory System

Terms in this set (30)

plasma
liquid part of blood
red blood cells
these contain hemoglobin; there are about 5 million of these in a cubic millimeter of blood!
hemoglobin
iron-protein structure in red blood cells that carries oxygen for delivery to cells
platelets
blood cell fragments that helps with clotting
white blood cells
help fight infection, viruses and all invaders; about 5,000-10,000 in every cubic millimeter of blood
artery
a blood vessel that carries blood away from the heart (often shown as red in pictures because these vessels carry oxygenated blood)
vein
a blood vessel that carries blood back to the heart (often shown as blue in pictures because these vessels carry deoxygenated blood-with the exception of the pulmonary vein)
aorta
largest artery in the body; takes blood from the heart to all regions of the body (systemic circulation)
superior vena cava
carries blood from upper body to right atrium
inferior vena cava
carries blood from lower body to right atrium
atrium (atria)
each of the two top chambers in the heart that receives blood into the heart
ventricle
two bottom chambers in the heart that are sending blood out of the heart
pulmonary artery
carries blood from the heart to the lungs; the only artery in the body that carries de-oxygenated blood
pulmonary vein
carries blood to the heart from the lungs; the only vein in the body that carries oxygenated blood
capillaries
the smallest blood vessels that connect arteries to veins.
What are the 3 kinds of circulation in the body?
-coronary circulation
-pulmonary circulation
-systemic circulation
Describe coronary circulation.
flow of blood to the actual tissues of the heart muscle; if coronary circulation is blocked or inadequate, a heart attack results
Describe pulmonary circulation.
flow of blood from the heart to the lungs and back to the heart again (this is how deoxygenated blood is exchanged for oxygenated blood)
Describe systemic circulation.
flow of blood from the heart to all parts of the body except the heart and lungs; this is the largest type of circulation in the body
The __________ventricle pumps blood out to the entire body through the largest artery called the ___________. (systemic circulation)
the left ventricle; the aorta
What special features do veins have that prevents blood from flowing backward?
Valves
The heart has 4 chambers and ____________that separate the atria from the ventricles & prevent the back flow of blood and keep it moving in a forward flow. The heart also has a _____________that separates the right side of the heart (deoxygenated blood) from the left side (oxygenated blood) and prevents blood from mixing.
Valves; Septum
Similarities between veins and arteries.
-both carry blood
-both have walls made of connective tissue and smooth muscle
-both can be affected by disease and poor diet
Differences between veins and arteries.
-veins carry deoxygenated blood back to the heart (except pulmonary vein)
-arteries carry oxygenated blood away from the heart (except pulmonary artery)
-veins have valves; arteries don't
What is known as the "tissue of life" and has many functions in the body.
Blood; blood plays a part in every body activity
What are the 5 functions of blood?
-carries oxygen from the lung to all body cells
-carries waste to the kidneys/lungs to be removed
-transports nutrients from the intestine to all body cells
-helps fight infection
-heals wounds
Red blood cells carry hemoglobin (which carries oxygen). What does the plasma carry?
nutrients & minerals are dissolved in plasma so they can be carried to all body cells; waste from body cells are also carried by the plasma and taken to the kidneys for removal
What is blood pressure?
the pressure of the push of blood from the ventricles; this pressure is what continues to move the blood throughout the body
Why is blood pressure often compared to a water hose?
Because the more blood, the higher the blood pressure (just like if you turned a water hose on to high).
Describe how platelets help clot wounds.
-after a cut, platelets stick to the wound and release chemicals called clotting factors
-clotting factors start a series of chemical reactions
-fibers called fibrin is made and start to make a sticky net
-this net traps blood and forms a clot, helping to stop blood loss from the cut
-white blood cells in the area start to fight off any bacteria that may have entered the body from the cut
THIS SET IS OFTEN IN FOLDERS WITH...