A9- Blood and Blood Vessels Flashcards
You have an expansive network of tubes inside your body designed to transport blood to and from the body and lungs
Blood Vessels
aorta
the largest blood vessel in the
body, connected directly to the heart; the
aorta branches into arteries that carry
oxygenated blood to the body tissues
A blood vessel that carries blood away from the heart towards the body tissues is called an…
artery
When are arteries nto carrying oxygenated blood?
The one exception to this rule is your pulmonary artery because it carries deoxygenated blood from right atrium to the lungs
The walls of the arteries are made of 3 layers of tissue
An outer layer of connective tissue
A middle layer of smooth muscle
A inner layer of epithelial (Endothelim) cells
What does the feeling of your pulse really mean?
you are actually feeling blood being forced through your arteries due to the contraction of your heart
TRUE OR FALSE: Arteries have valaves?
FALSE
Arteries do NOT contain valves!
As arteries branch off, they get smaller and smaller along the way
These smaller vessels are called the…
arterioles
What happen to artieris when heart conmtratcs and send blood around body?
Arteries expand
TRUE OR FALSE: Outer layer of arteries has elastain fibers that gives vessels elasticity
TRUE
arteriole
the smallest artery, with smooth
muscle in its walls
vasodilation
an increase in the diameter
(dilation) of arterioles that increases the
blood flow to tissues
vasoconstriction
a decrease in the
diameter of arterioles that decreases the
blood fl ow to tissues
What type of muscle does arterioles have in their walls?
Smooth muscle in the walls
How do arterioles regulate their diamter?
nerves
What gives our faces a flushed look?
Nerve impluses in the smooth muscle in the arterioles in the skin can relax, which increases diamteter of blood vessles to give a flushed look
When smooth muscle inarterioles are relaxed…
diameter of bkood vessels increase which open the vessel
When body is cold what happenes to the vessels?
Vessels can close to restrict blood flow to skin to prevetn loss of heat
When an arteriole reaches the body tissue, it branches into the smallest vessel called …
capillaries
The walls of capillaries are only…
one cell layer thick and wide
What do caplilaires do?
provide oxygen and nutrients to every cell in the body
Where are capilaries found?
often are found in networks called capillaries beds
Capillaires facilitie exchange of…
waste, nutrients, gases, hormones between blood and body cells
How do nutrients and gasses like CO2 and O2 diffuse in capillaires?
Through the membrane
How do larger materails move through capillaries?
move through fluid filled spaces with capiliar cell mebranes
Interstial fluid contains…
-water
-nuittents
-gases
-wastes
-small protiens
Why is it a good thing that speed of bloodflow drops quickly while blood is forced into capalliaries?
Enchances diffusion
Higher fluid pressure on arterial side of capillary netwirk cause water to…
diffuse from blood into tissue fluid
Reduced concentration of water in blood increases the…
concentration of discolved substances and protiens in the blood increases the concentration of dissolved substanes and protiens in the blood as it corsses the capiliary network
Pre-capillary spinchinter
Is where the arteriole branches into a capillary. Th ese sphincter
muscles serve the same function as the dilation and constriction of arterioles.
What does the pre-capillary sphincter do when blood is not needed?
the pre-capillary sphincters contract
and reduce blood fl ow
What does the pre-capillary sphincter do when blood is needed?
arterioles and
sphincters are fully relaxed, and the blood fl ow to the muscles is increased.
venule
the smallest vein; formed by the
merging of capillaries
After the oxygen has diffused out of and the carbon dioxide has diffused into the blood, it needs to return to heart and lungs
After the capillary bed, it will enter…
venules
Venules and veins carry…
wastes and carbon dioxide back to the heart and lungs where it can be expelled
Veins almost always carry…
deoxygenated blood away from the tissues and towards the heart
The one exception in veins is…
the pulmonary vein because it carries oxygenated blood away from the lungs and towards the heart (i.e. the left atrium)
Veins have the same three layer structure as arteries but…
but have a thinner layer of muscle and a wider opening
Valves and skeletal muscle contractions helps the blood…
fight gravity and push back towards the heart
Most veins contain valves that can…
open and close
TRUE OR FALSE: Arteries have lower blood pressure then veins
False
- Veins have lower blood pressure
Why do arteries have thicker walls?
- so that they can handle high pressure of blood moving through them and transport blood around the body
Why are veins thinner?
- blood in veins has less pressure
3 major types of blood vessels?
- Arteries
- Veins
- Capiliares
Cells dump ____ into caoiularies and back into the the blood they go
CO2
Capilary beds aid with?
- Exchange nutrients
-regulate blood pressure
role in thermoregulation
Cells send theri CO2 to the…
Venal end of the capilairy exchange
- Capillaries unite into venuls and merge into veins which go back to the heart
Why do pressure in the vessels need to be dropping?
Because fluid is always flowing from high to low pressure
V.enus valves
Since veins have low blood pressrue these valves prevent blood from flwoing backwards
- Without we would deal with hemorids
Veins have a more broad lumen which allows for them to handle…
larger volumes of blood.
Blood
the red fluid that circulates throughout our blood vessels
bloods function
to act as the fluid in our body’s transport system, useful in immune system too
Why are blood donors important?
Because there is no real sub for blood
erythrocytes
Red blood cells. They are binocave shaped cells
Why is the shape of the red blood cell important
This cell shape is advantageous because it increases the surface area which allows for more gas exchange
Function of red blood cells?
to carry oxygen from the lungs to the body and carbon dioxide from the body back to the lungs
What does O2 attach to?
hemoglobinc
serum
m the fluid that results when the
cells, platelets, and fibrinogen have been
removed from whole blood
Red blood cells are formed in..
stem cells in the marrow of the vertebrae, ribs, breastbone, skull, and arm and leg bones
What happens when red blood cells die?
After about 120 days in circulation, they will die and will be removed from the body by the liver or spleen
Oxygen
is transported by the erythrocytes around the body and diffuses…
from the blood into
the tissue fluid, and from the tissue fluid into each cell.
leukocytes
White blood cells
Function of leukocytes
are your body’s first line of defense against harmful bacteria, viruses and organisms
What process do leukocytes go through when they want to distroy something?
phagocytosis
How are white blood cells formed?
formed in the bone marrow
Phagocytosis
involves engulfing the bacteria within the cell membrane. One the cell has engulfed the target, enzyems are then released asd destroy the target and the leukocyte itself
pus
a yellowish-white fluid formed in
infected tissue, consisting of white blood
cells and cellular debris
2 catagories of leuckocytes
- granular
-agranular
Granular
- smaller grain in cytoplasma
- granules contain different chemicals to attack forgien materials
- attraced to killing bacteria
Types of gunular leuckocytes
Types:
-neutrophils
- eosinophils
-basophils
Agraunlar
- engulfs bacteria
Types of Agraunlar leuckocytes
-lymphocytes, monocytes
- monocytes grow into macrophage which clean up debris in our blood
platelet
a cell fragment in the blood that
is necessary for blood clotting
How are platelets produced?
produced from stem cells in the bone marrow
Function of platelets?
They are essential in the blood clotting
- When a blood vessel is broken, the platelets form a clot so that too much blood isn’t lost
Stem cells
Stem cells, specifically blood stem cells, are immature cells that can develop into any cell present in the bloodstream. Without stem cells, the body cannot make the blood cells needed for the immune system to function.
When patients need a stem cell transplant, it means…
their bone marrow (stem cell factory) has failed due to an illness
3 ways to donate stem cells?
- Bone marrow
-Phripheral Bloo dtsem cells (in bloodstream)
- Unblilical cord
Plasma
a protein-rich liquid in which blood cells and platelets are suspended
-It is yellow in colour and will rise to the top if you were to centrifuge a blood sample
What is the makeup of plasma
90% water but also has many dissolved substances in it including oxygen, proteins, glucose, minerals, etc.
blood proteins present in plasma include…
albumins, globulins, and fibrinogen
albumins
dtermine how much water enters and leaves bloodstream through osmosis
globulins
transports lips, chlostrol, fats
Fibrinogen
helps with blood clotting
Blood compostion
55% Plasma
40-45% Red Blood Cells
0.7-1% White Blood Cells
Less than 1% Platelets
What are the eight blood groups?
A+
A-
B+
B-
O+
O-
AB+
AB-
How is blood type determined?
- The presences or absence of sugars called markers on the cell memebrane of erythrocytes
What are the 2 marks?
A and B
If someone has none of the markers what blood type would they have?
Type O
Why does incompabalilty occur with blood types?
Because marker act as antigens
- When immune system finds antigen it blocks blood vessels and prevnts circulation
Why is type O a universal blood type?
-has no markers so everyone can take it but people with this blood type can obnly take type O blood
Explain donation process of type AB
- Type AB can take all blood types since they have both marks but cannot give their blood to all other blood types
RH system
- Another antigens
-You either have all 45 different antigens or you have none of them
RH+
- If you have all 45 antigens you’re RH+
- You can take + or -
RH-
- If you don’t have all 45 then you’re RH-
- You can only take -
CBC
- Complete blood count
- A hemocytometer is used to estimate # of ethrocytes, leuckocytes and platelets in a volume of blood
Group A blood
Antibodies= Anti-B
Antigens= A antigen
Group B blood
Antibodies= Anti-A
Antigens= B antigen
Group AB blood
Antibodies= none
Antigens=A and B antigen
Group O blood
Antibodies= Anti-A adn Anti-B
Antigens= none
Artifical blood
- Currently people are tying to be artifical blood because a supply of blood may nto always be safe
- They’re fopcusing on the transport function of blood
Currently there is two works in progress:
-hemoglobin-based oxygen
carriers (uses cow or human blood, but cou8ld have a toxic effect on kidneys)
- perfluorocarbon emulsions (synethic)
