Physiology exam 2
sickle-cell disease consequences - ✔️✔️Leads to anemia, shortness of breath, fatigue,
paleness, delayed growth and development
red blood cell anatomy - ✔️✔️RBCs consist of a plasma membrane enclosing a cytosol
rich with hemoglobin
No nucleus and limited organelles
(to make more space for carrying oxygen)
cannot reproduce or carry out extensive metabolic activities
sickle-cell disease - ✔️✔️Inherited disease
RBCs contain Hb-S, an abnormal type of hemoglobin
Release of oxygen causes Hb-S to form stiff-rodlike structures. It bends the erythrocytes
into a sickle shape.
Sickled cells easily rupture. Erythropoiesis cannot keep pace with the hemolysis.
Sickled cells also tend to stick together and block vessels, which can cause pain and
organ damage
functions of blood - ✔️✔️transportation: (Gases: O2 and CO2, Nutrients and wastes,
Other: hormones, heat)
regulation: (Blood pH: 7.35-7.45, Body temperature, Water content of cells)
protection:(Clotting,Leukocytes: phagocytes, lymphocytes, Certain plasma proteins:
antibodies, interferons)
composition of blood - ✔️✔️plasma 55%
red blood cells 45%
buffy coat composed of white blood cells and platelets (<1%)
composition of plasma - ✔️✔️55% of blood volume
91.5% Water: solvent and suspending medium
8.5% Solutes: 7% plasma proteins + 1.5% other
Plasma proteins: Albumin, globulins, fibrinogen
Albumin: 54% of all plasma proteins, regulate blood osmotic pressure
Globulins: 38% of all plasma proteins, antibodies
Fibrinogen: 7% of all plasma proteins, clotting
Other solutes: gases, nutrients, electrolytes, etc
, Albumin - ✔️✔️plasma protein
54% of all plasma proteins, regulate blood osmotic pressure
fibrinogen - ✔️✔️plasma protein
7% of all plasma proteins, clotting
hematocript - ✔️✔️measures the volume of whole blood made up of erythrocytes
also called the "packed cell volume" (PCV)
reported as a % of total blood volume
normal ranges for hematocript - ✔️✔️Males: 40-54%, Females: 38-46%
why is female hematocripts lower? - ✔️✔️because women lose blood every month
A significant drop in hematocrit indicates - ✔️✔️Anemia: body does not have enough
healthy RBCs
A significant rise in hematocrit indicates - ✔️✔️polycythemia
polycythemia - ✔️✔️abnormally high number of RBCs
caused by abnormal increase in erythropoiesis from hypoxia, dehydration, doping
hemopoiesis - ✔️✔️the production of the formed elements in the blood.
where formed elements are formed (homeopoiesis) - ✔️✔️Occurs in the red bone
marrow of bones of the axial skeleton, pectoral + pelvic girdles, and proximal epiphyses
of humerus + femur.
order of formed elements development - ✔️✔️Pluripotent stem cells develop into
Myeloid stem cells: give rise to RBCs, platelets, eosinophils, monocytes, basophils, +
neutrophils
Lymphoid stem cells: give rise to lymphocytes (T cells, B cells, and natural killer cells)
shape of RBC - ✔️✔️Bi-concave disc shape -
to increase the surface area so that more oxygen can diffuse into the cell
plasma membrane of RBC - ✔️✔️Plasma membrane is strong and flexible to allow it to
pass through the capilaries and contains antigens that account for blood "type
hemoglobin - ✔️✔️Globin protein
One RBC contains ~280 million hemoglobin molecules
hemoglobin structure - ✔️✔️Globin protein