BIOL 436 Final Exam Questions and
Verified Answers
Plasma is ✅55% of the blood, fluid component of blood
Small soluble components of the blood ✅antibodies and antigens
Formed elements of the blood ✅also known as cellular elements, consists of red blood
cells white blood cells and platelets
Rbc have ✅also known as erythrocytes,make up 45% of the blood, have a lifespan of
about 4months, carry oxygen, don't have nucleus or mitochondria (very dense because
of this), have sodium potassium atpase pumps
Platelets make ✅also known as thrombocytes, make atp,live 5-9 days, have no
nucleus or mitochondria,always making new
Wbc ✅also known as leukocytes, have mitochondria and nucleus, multiply through
mitosis
Hematocrit ✅percentage of blood that consists of rbc, normal is 45%
Buffy coat ✅consists of white blood cells and platelets and sits in between rbc and
plasam
Anemia ✅low elvels of rbc (below 30%)
Polycythemia ✅high levels of rbc (above 70%)
Erythropoietin (epo) ✅hormone made in the kidney that goes to red bone marrow to
stimulate the precursor of rbc to differentiate into mature ones
Hemoglobin (hb) ✅iron-containing oxygen transport protein, found in rbc's, responsible
for oxygen transport in the blood, consists of 4 polypeptide chains and 4 heme groups,
allows it to carry 4 oxygens
Heme ✅found on polypeptide chains of hemoglobin, able to carry 1 oxygen
Agglutination determines ✅blood type
Universal donor ✅there are no antigens on the cells so they can go to anyone because
their antibodies wont have anything to react to (type o)
,Universal recipient ✅they have no antibodies so they wont react to any antigens
present (type ab)
Chylomicron ✅lipoprotein that transports cholesterol and lipids from the intestines to
the liver via blood
Ldl ✅low density lipoprotein:transport cholesterol and lipids from liver to tissues, too
much is bad because can lead to "plaque" buildup and arteriosclerosis
Hdl ✅high density lipoprotein: transport excess cholesterol from tissues to liver,
properly disposed of, or stored in liver for future use
What can be determined by a person's hematocrit? ✅if a person has anemia or
polycythemia
Iron deficiency anemia ✅inadequate amount of iron in the body prevents manufacture
of hemoglobin
Aplastic anemia ✅when the bone marrow doesnt make rbc because it doesnt respond
to the epo
Pernicious anemia ✅lack of b12 which is used to make thyadine (dna) which is used to
make rbcs
Hemolytic anemia ✅rbcs are destroyed and removed from the bloodstream before
normal lifespan is over(sickle cell is a type)
What does esr stand for? ✅erythrocytes sedimentation rate
Can the esr be used to diagnose diseases? ✅disease can causes fibrin (inflammation)
produced in the blood which links rbc to settle quicker making a faster esr, associated
with diseases and cancer can be used to measure progression but not to diagnose
completely, can help to. Pin. Point angina and if there is a heart attack the esr will be
sped up
How long do mature rbcs survive? How does the body replace them? What organ is
responsible for this? ✅mature red blood cells live up to 4months, the kidneys sense
low levels of oxygen in the blood and release the hormone erythropoietin which
stimulates the red bone marrow to differentiate precursor rbc into mature ones by
getting rid of the nucleus and mitochondria and filling it with hemoglobin
What is hemoglobin? Where is it found? How does hemoglobin help rbc's carry oxygen
to tissues? ✅hemoglobin is made up of a polypeptide chain and contains 4 subunits
,called heme, each heme has an iron molecule which is what complexes oxygen, there
are 280 million hemoglobin in 1 red blood cell and 1 red blood cell carriers over 1 billion
oxygen.blood passes through lungs, hb binds the oxygen to its heme group, due to
increased oxygen pressure in the capillaries in the lungs, and releases the oxygen to
tissues where the oxygen pressure is lower
What is essential for hemoglobin to function? ✅iron is recycled and hemoglobin is the
right shape
What are antigens ✅antigens are proteins lipids or carbs found on the cell membrane
of a rbc and cause b cells to create antibodies to it.
Your blood type refers to ✅the antigens present on your rbc
If you have a antigens on your cells ✅you have type a blood and you make b
antibodies
If you have both a and b antigens on your cells ✅you have ab blood type and make no
antibodies
If you have b antigens on your cells ✅you have type b blood and make a antibodies
If you have no antigens on your cells ✅you have type o blood and make both a and b
antibodies
If you have a blood sample and you put it in anti b(antibody b) and it clumps that means
that you have ✅b antigens present on the blood meaning you have type b blood
If you put a blood sample in anti a and it clumps that means that you have ✅a antigens
on your cells and you have type a blood
If you put it blood in both anti a and b and it clumps in both that means ✅both anitgens
are present on your blood and you have ab blood
Why does cholesterol pose a special problem for transport in our circulation? How do
our bodies transport cholesterol (along with some triglycerides and phospholipids) ✅.it
is water soluble, needs to be wrapped in protein packages (lipoproteins) in order to
travel in the bloodstream from the liver
What is the major organ responsible for synthesizing cholesterol for our bodies? ✅the
liver which packages it in ldl
What do the terms chylomicron, hdl & ldl refer to? Which is the "good" lipoprotein?
Why? ✅chylomicrons transport cholesterol and lipids from intestine (dietary) to liver via
, blood. Ldls transport cholesterol and lipids from liver to tissues. (too much is bad,
because if you build up cholesterol and lipids in tissues, i.e. In arteries, this leads to
"plaque" build-up and arteriosclerosis.)Hdls transport excess cholesterol from tissues
and delivers it to liver. (hdl = healthy, excess cholesterol from tissues is "properly"
disposed of or stored in the liver for future use.)
The basic contractile unit of a cardiac muscle (myocyte) is ✅a sarcomere
Cardiac fibers or cells don't ✅stretch entire length or width of heart
Cardiac myocytes are ✅small cells linked together by intercalated disks to create long
fiber like structures, small cells are linked together to create long fibers
Cells linked together at ✅intercalated disks
Intercalated discs ✅- help hold cardiac muscle cells together and transmit force of
contraction from cell to cell
- allows myocytes to come together (contain gap junctions and desmosomes)
Desmosomes ✅-form tight connections so that cardiac cells dont pull apart when they
start to produce force to make contraction of heart
-made up of multiple proteins, proteins on inside of membrane on each adjacent cell
forms as an anchor, proteins extend out into the interstitial space and act as velcro cuz
wrap around each other
-50 to 100 in intercalated disc
-don't really stretch
Gap junctions provide a way for ✅-open up enough to have multiple things pass
through them
-sodium, calcium or small amino acid or any type of ion, not selective on what it allows
through from one cell to another only small ions or small molecules or amino acids,
-made up of proteins called connexons,
-used to think they were always open but actually they can open and close, a cell can
have some say on if a gap junction is open, if a myocyte dies the gap junction remains
closed so things don't leak through
-provides direct communication from one cell to the next, viewed as direct electrical
connection because substances like sodium and calcium diffuse through, if they diffuse
through and stimulate one cell and cause an action potential and sodium and calcium
leak through that can cause neighboring cell membranes to reach threshold,not
channels because they allow a lot of the small ions (na+, ca2+,etc)to transfer past
-provide openings for electrical continuity and propagation throughout the heart.
Cells are branched so they can ✅make connections with multiple cells
