SCB 203 Lectures 23-25 Summary

SCB203 – Study Guide Lectures 23-25


Lecture 23: Blood and its Functions
 Describe the seven functions of blood
o Exchanging gases
o Distribution of solutes
o Immune functions
o Maintain body temperature
o Seal wounded blood vessels via blood clots
o Maintaining acid-base homeostasis
o Stabilizing blood pressure
 Describe the components of blood
o Plasma
 Makes up 55% of blood volume
 Contains
 Water
o Primary component of plasma  90%
o Amount will determine blood viscosity
 Less water  blood becomes more viscous
 Proteins
o Make up 9% of plasma volume
o Proteins made mostly by liver
o Will not dissolve in water due to size  forms colloid
mixture
o Important plasma proteins
 Albumin
 Large protein made by liver
 Function
o Responsible for blood’s colloid
osmotic pressure
 Pressure draws water into
blood via osmosis
 Immune proteins
 Antibodies
o Produced by leukocytes
 Transport proteins
 Are hydrophilic
 Help move lipid-based compounds
 Lipoproteins and beta-globulins are
examples

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,  Clotting proteins
 Help form blood clot along with platelets
to stop bleeding from wounded blood
vessels
 Solutes
o Make up ~1% of plasma volume
o Will dissolve in water found in plasma to make a
solution
o Examples of solutes found in plasma
 Glucose
 Amino acids
 Nitrogenous wastes
 Ions
 Small amounts of oxygen and carbon dioxide
 Describe the disease cirrhosis
 Also known as liver disease
 Caused by
o Cancer
o Alcoholism
o Viral hepatitis
 Consequence of cirrhosis
o Decrease in production of plasma proteins
 Albumin
 Decrease results in reduced blood
osmotic pressure
o Blood will lose water to
extracellular spaces and swelling
will ensue
 Clotting proteins
 Decrease will result in easy bruising and
delays in blood clotting
o Erythrocytes (Red Blood Cells  RBCs)
 One of the three formed elements in blood (leukocytes [white blood
cells- WBCs] and platelets are the others - described below)
 Makes up 44% of total blood volume also known as the hematocrit
 Males tend to have a higher hematocrit (40-50%) than females
(36%-44%)
 Life span of a RBC is ~100-120 days
o RBCs do not have cellular machinery to make new cells
or repair damage that occurs to RBCs
 Describe the structure of RBCs
 Biconcave disc

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