Midterm 3 Flashcards
What is the average blood volume of males and females?
Women - 5.0L
Men - 5.5L
What are the three main roles of blood?
Transportation - nutrients, hormones, waste
Regulation - Body temp., electrolytes, blood sugar
Protection - antibodies, WBCs, clotting factors
What shape is a RBC?
Biconcave discs
How much of the blood is plasma? (%)
55-58%
How much of the blood is Erythrocytes (RBCs)? (%)
42-45%
How much of the blood is the buffy coat (WBCs & platelets)? (%)
Less than 1%
What are normal hematocrit levels in males and females?
Men = 42-52
Women = 37-47
what is the main characteristic of low hematocrit?
Lower oxygen carrying capacity
How many RBCs are the per cubic mm of blood?
~ 5 million
What is the main benefit of the biconcave shape of the RBC?
- Favors diffusions of CO2 and O2
Why do RBCs have a short lifespan?
They have no nucleus or mitochondria
What is spectrin and what does it do?
- A fibrous protein found in the cytosol
- Gives shape and flexibility of RBCs
What do glycolytic enzymes do and why are they important for RBCs?
Enzymes that rely on anaerobic glycolysis to create ATP
Important that is the only way for RBCs to create ATP (RBCs contribute to blood lactate b/c of this)
What is carbonic anhydrase and what does it do?
An enzyme that allows the conversion of
CO2 + H2O <–> H2CO3 (carbonic acid) <–> H + HCO3 (bicarbonate)
this occurs when CO2 binds to hemoglobin
How long is the lifespan of an RBC?
~ 120 days or 3-4 months
Why can’t RBCs repair, duplicate, or grow?
They do not have a nucleus and therefore do not have the genetic code (DNA) to do any of these things.
In a healthy person, how much O2 is in each liter of blood?
~200mL / L of blood
How much (%) oxygen is carried in the plasma vs. bound to hemoglobin?
Plasma = ~1.5%
Bound to Hb = ~98.5%
How many oxygen molecules can one hemoglobin carry?
4 oxygen / Hb molecule
What is hemoglobin important for?
Carrying CO2 and O2, buffering H+ ions
How many subunits does a hemoglobin molecule have? and what are they called?
4 total subunits - 2 alpha and 2 beta
Where is the heme molecule in a hemoglobin and what is inside it?
In the centre of the hemoglobin, inside is iron
What molecules can hemoglobin carry? and what molecule has the highest affinity?
O2, CO2, H+, CO (carbon monoxide)
carbon monoxide has the highest affinity
How much hemoglobin is in healthy blood?
15g/100mL
What is the law of mass action and how does it apply to hemoglobin?
it means that the first oxygen is the hardest to bind to the hemoglobin but once the first one binds the rest happen very quickly.
What does saturation of hemoglobin measure?
How much oxygen is bound to hemoglobin
(100% = all subunits carry oxygen)
What does the hemoglobin-oxygen dissociation curve show?
Shows the difference in hemoglobin saturation from when the blood leaves the lungs (almost fully saturated) to when it returns to the heart. (less saturated due to oxygen offloading to the tissues)
In normal functioning, how saturated is hemoglobin when it returns to the heart?
~75%
What does a rightward shift in the hemoglobin-oxygen curve mean? and what can cause it?
Decreased Hb affinity for O2
- harder to load O2 but easier to offload
causes:
- increased temperature due to metabolically active tissues
- decreased ph
what does a leftward shift in the hemoglobin-oxygen curve mean? and what can cause it?
Increased Hb affinity for O2
- Easier to load but harder to offload O2
causes:
- increased ph (more H+ = more likely to bind to Hb)
What affect does CO2 have on hemoglobin?
when bound to Hb, Hb has a lower affinity for O2 -> increasing offloading of O2 in the tissues
(more CO2 -> more effect)
What are the three types of hemoglobin?
Type A - adult Hb (2 alpha & 2 beta subunits)
Type F - fetal Hb (has alpha and gamma subunits) (has higher affinity to allow O2 transfer from mother to fetus)
Type S - sickle cell Hb (causes anemia)
Where are RBCs made and what is the process called?
in the bone marrow of long bones
erythropoiesis
what are the cells called that all blood cells differentiate from?
hematopoietic stem cells
what stimulates erythropoiesis and how is it made?
erythropoietin is generated in the kidneys if blood oxygen in the kidneys is low
what is anemia and what is it characterized by?
abnormally low O2 carrying capacity of the blood
- reduced RBC count
- reduced Hb in blood
What values make you considered anemic?
if Hb < 12g/100mL
- or -
if hematocrit <37%
What are 7 layers of defence the cell has against invaders?
- Skin
- Antibodies/WBCs
- Cell membrane
- Endosomes
- Protein searchers
- Protosomes
- Nuclear membrane
What is a bacteria?
Single-celled organism, can survive & reproduce on its own
What is a virus?
consists of nucleic acids in the protein shell
must invade another cell to survive
What is the innate immune system?
a non-specific immune response that starts immediately with exposure to a threat
what is the acquired immune system?
relies on specific immune responses to selectively target foreign materials that the body has past experience with
what does it mean if a leukocyte is granular?
has granules in the cytoplasm, has lobulated nucleus (lobes = not round)
what leukocytes are granular?
neutrophil, eosinophil, basophil
what leukocytes aren’t granular?
Monocytes, lymphocytes
What do selectins do for leukocytes?
Cell adhesions (selectins) cause leukocytes to slow down which allows them to check for stress signals from cells
what is diapedesis?
the ability to pass through cell walls
What leukocytes are most important for the innate immune system?
Neutrophils and macrophages
How does the innate immune system deal with infection?
antibodies recognize bacterial/viral markers and bind with them to mark them for destruction by phagocytes
how are WBCs attracted to sites of injury?
Chemotaxis - chemical substances from cells/bacteria and bind with neutrophils to allow Ca ++ inside to allow for ameboid movement down concentration gradient
How do neutrophils deal with foreign proteins?
the engulf them (has many lysosomes to help digest engulfed cells)
what are eosinophils main purpose?
to detoxify foreign substances (render foreign invaders harmless)
cells strategically placed in vulnerable areas
what are some characteristics of basophils?
rarest of the leukocytes, found more outside of the blood, granules contain histamines (increasing blood flow & inflammation)
What are some characteristics of monocytes?
largest leukocyte, develop into macrophages, tissue bound phagocytic cells
what do natural killer cells do?
travel through the body and scan cells, if they see an abnormal cell, they kill it
what are the two types of lymphocytes?
T cells (antibody mediated) and B cells (cell mediated)
what is an antigen?
a protein that could potentially be dangerous but also could be completely harmless, however the body attacks it either way
(harmless antigens cause allergic reactions)
what are some characteristics of T-lymphocytes?
~70% of total lymphocytes
quite motile
directly attack antigens
can attack invaders that are inside cells
how do t cells get their receptors?
they differentiate from stem cells and then pass through the thymus where receptors are inserted into them by thymosin
what are the two subtypes of T lymphocytes?
cytotoxic - attack cells
helper - facilitate activation of b cells and cytotoxic t cells
what is the importance of memory t cells and how are they made?
made through staying alive post infection, important b/c they carry the info needed about the antigen so the next response can be faster
What do most B-cells do when activated by an antigen?
differentiate into an active plasma cell that produces thousands of antibodies/second
What are antibodies and what do they do?
proteins secreted into the blood that bind with antigens to guide the immune response by “flagging” invaders
what is the goal of immunizations?
to help the acquired immune system develop before exposure to the full/operational disease
What is passive immunity?
when antibodies against a certain invader are injected into another persons body to help with immediate immunity (doesn’t induce any long term immunity)
how do allergies occur?
when the body overreacts to harmless proteins that enter the body (always acquired response)
what happens in anaphalyxis?
histamines are released throughout the body, causing widespread vasodilation, meaning blood doesn’t return to the heart as much, leading to a huge increase in blood CO2 and a drop in O2
what are autoimmune diseases caused by?
overactivity of the immune system
how are blood types, typed?
they can contain antigen, labelled “A” or “B”, and will have the opposite antibody circulating in their blood
what happens if someone recieves the wrong blood transfusion?
antibodies in the bloodstream will bind to the new blood causing clotting and bursting of RBCs
how is it determined if you are + or - blood type?
if the Rh (rhesus factor) is present = +
if not = -
meaning anti rh antibodies are produced in rh negative people
what is hemostasis? and what are the three steps?
blood clotting in response to injury
steps:
1. local vasoconstriction
2. platelet activity to help w clotting
3. activity of clotting factor proteins to help clot
what is the production of platelets called and how does it work?
thrombopoiesis - generates megakaryoblasts that mature into megakaryocytes and then fragment into thousands of platelets
how do platelets act as a positive feedback loop?
activated platelets activate other platelets & interact with proteins to form fibrin which traps other platelets into the clot
where is thrombin produced and what does it do?
produced in the liver
thrombin converts fibrinogen into fibrin which creates a ‘net’ to trap platelets & blood cells to create the clot
how many clotting factors are there?
12
what is the goal of clotting factors?
to produce thrombin to change fibrinogen into fibrin
why is vitamin k important for blood clotting?
it is required for synthesis of at least four of the clotting factors
what is albumin? (purpose and origin)
~60% of plasma proteins
made by liver
helps maintain blood volume & osmotic gradient
carries hormones, vitamins, and enzymes
what are globulins? (purpose and origin)
~40% of plasma proteins
produced by liver & immune system
have three categories (alpha, beta, gamma)
what do alpha globulins do?
alpha 1 - lipid transport & hormone formation
alpha 2 - erythrocyte production & blood coagulation
what do beta globulins do?
carry lipids
what do gamma globulins do?
are the antibodies
what are some systematic responses to exercise?
+ peripheral blood circulation
+ cardiac output
+ vascular elasticity
how many exerkines (exercise factors) are there? and where are they made?
~200 exercise factors that up or down regulate themselves based on amount of exercise
secreted by the liver (mostly)
how do muscle satelite cells respond to exercise?
increase cross-sectional area
hypertrophy
how do WBCs respond to exercise?
increase circulation & slight increase in amount of WBCs with regular exercise
how do RBCs react to exercise?
+ total Hb
+ total RBC mass
- average age of RBC
+ plasma volume
how do brain cells react to exercise?
+ executive function
+ mood
- stress
+ release of NTs
how do cardiac cells respond to exercise?
exercise allows for activation and promotion of regeneration of myocardial cells
how do mitochondria react to exercise?
increases the number and volume but can cause excess free radicals that can damage DNA if left unchecked
what is angiogenesis and how does it respond to exercise?
increase capillarization
exercise induces angiogenesis
how do telomeres respond to exercise?
slows aging
how do muscles react to exercise? (not hypertrophy)
contractions increase muscular metabolism
