Without reference, identify at least four out of
six principles about anatomy and physiology
as they relate to laboratory systems

Function of blood
 One of the body's connective tissues
 Transports oxygen from the lungs to the cells and
carbon dioxide waste from the cells to the cells.
 Protect the body from disease
 Carries nutrients from the digestive system to the
cells
 Transports waste from the cells to the kidneys
 Composition
 Blood contains red blood cells, white blood
• cells, and fragments of cells called platelets suspended
in a water-based, pale, somewhat yellow fluid known
as plasma.
 The average human has 5 liters of blood
 Accounts for 8 percent of the total body
weight
 Blood is alkaline with a pH between 7.35
and 7.45
• Acidosis
• alkalosis

Definition: liquid portion of whole blood with
the cells removed.
 fluid portion of the blood
 blood has not clotted

Components of plasma:
 92 percent water
 7 percent protien
 1 percent ions






Sodium (Na+)
Potassium (K)
Calcium (Ca)
Magnesium (Mg)
Chloride (Cl-)
Bicarbonate (HCO3-)

Definition: plasma minus it‘s clotting factors
such as fibrinogen
 Liquid portion of clotted blood
 Blood is allowed to clot and the clear serum is removed
(no fibrinogen or other clotting factors)
 Most commonly used body fluid for chemical
analysis

Characteristics
 also known as erythrocytes
 Have little internal organization and no nucleus or
organelles
 organelles are small structures within cells which
perform dedicated functions
 basically a small organ within a cell
 Each blood cell is a flexible, biconcave disk (thinner
at the center than at the edge)
 Primary purpose of RBC's in the body is to transport
oxygen
 Number of RBC's in the body
 average adult male has approximately 5.4 million
RBC's per cubic millimeter (microliter)
 average adult female has approximately 4.8 million per
cubic millimeter of blood
 RBC Production
 RBC's are produced in the red bone marrow of bones.
 The process of RBC formation is called erythropoiesis
 Contained in the ecytoplasm of red blood cells
• Hemoglobin is a protein chemical which has a red
pigment that gives it's color to erythrocytes
 Hemoglobin contains the element iron, making it an
excellent vehicle for transporting oxygen and carbon
dioxide
• As blood passes through the lungs, oxygen molecules
attach to the hemoglobin
• as the blood passes through the body‘s tissue’s, the
hemoglobin releases the oxygen to the cells
• the empty hemoglobin molecules then bond with the
tissue's carbon dioxide or other waste gases
 Red Blood Cells circulate in the bloodstream for
approximately 120 days.
 Older cells and damaged cells are then engulfed by
phagocytes in the spleen, liver, and bone marrow,
and the red blood cells are broken down
 The hemoglobin is broken down to release it's
amino acids, which can be reused for synthesizing
new protein
 The iron portion of the hemoglobin is brought to
the bone marrow for new hemoglobin formation,
and any excess iron is stored in the liver

Primary Function: to defend the body‘s tissue
against infection and substance foreign to the
body
 A normal adult has approximately 7000 white blood
cells per cubic millimeter of Blood

Types of WBC's (5 different types in two
major groups)
 Granulocytes which have granules in their
cytoplasm and include the following:
 Neutrophils
 comprise about 60 percent of the white blood cell
count in the body
 the neutrophil's primary function is phagocytosis
(devours foreign substances)
 Basophils
 least numerous blood cells
 help initiate inflammation process at the site of an
injury
 Eosinophils: function during an allergic reaction

Agranulocytes have no granules in their
cytoplasm and include the following:
 Lymphocytes
account for about 30 percent of all white blood
serve as an important part of the body’s immune system
 Monocyes
largest of all white blood cells
function primarily as phagocytic (engulfing) cells

Purpose for examination of WBCs
 White blood cell population of the body can provide
valuable insight into disease
 An elevated white blood cell count may indicate a
microbial infection
 Also, noting whether particular WBC’s are high in
number can be valuable.
 This data is obtained by a differential white blood
cell count
 a general reduction of white blood cells is called
leucopenia
 an above average population of white blood cells is
called leukocytosis
 leukocytosis may also indicate cancer of white
blood cells called leukemia

Characteristics
 also called thrombocytes, platelets are blood
elements produced in the bone marrow
 technically, platelets are not cells because they
consist of fragments of cytoplasm enclosed by
membranes
 Platelet production
 platelets form from large cells called megakaryocytes
in the red bone marrow
 bits of megakaryocyte cytoplasm pinch off within
membranes and are released into circulation
 approximately 300,000 platelets exist per cubic
millimeter of blood
 Platelet function
 work along with fibrinogen, calcium, and vitamin K to
form clots
 a clot begins to form when blood is exposed to air
 a dried external clot is a scab
 an internal clot is a bruise
Homeostasis of the body environment
depends on a balance of fluids, electrolytes,
acids and bases
 In the normal body, the levels of fluids and
electrolytes remain constant

 the input of water and electrolytes is balanced by
selective elimination through the excretory system
 if serious depletion occurs immediate replacement
is critical
 Electrolyes
• the products of substances that dissociate into
electrically charged components when they dissolve in
water
• for example, the compound sodium chloride
dissociates into sodium ions and chloride ions, which
are electrolytes carrying electrical charges
 Acid
 a chemical compound that liberates hydrogen ions into
a solution
 examples of acids in the body are hydrochloric acid
and lactic acid
 Base
 a chemical compound that takes up hydrogen ions
from a solution, leaving the solution with an excess of
hydroxyl (-OH) ions
 a base in the body is ammonia

Body fluids

the fluid content of the body refers to the
amount of water in the body

the amount of water can vary, depending upon
the weight, sex, age, and fat content of the
individual
 for instance, woman have a relatively lower water
content than men because a woman's body contains a
higher percentage of , and fat tissue contains very little
cellular water
 water makes up about 60% of the body weight for an
adult male and about 50% of a female's body weight

Fluid compartments: The body's total water
content can be divided into two fluid
compartments
 Intracellular fluid compartment
 refers to the water in all body cells
 almost two-thirds of the body's water exists in this
compartment

Fluid compartments
 consists of the body area outside the cells
 extracellular fluid provides a relatively constant
environment for the cells

Extracellular fluid compartment continued
 approximately one-third of the body water exists in
this compartment
 extracellular fluid contains large amounts of
sodium, chloride, and bicarbonate ions and small
amounts of potassium, magnesium, calcium,
phosphate, sulfate, and organic ions
water enters the body through the digestive tract
and as a result of chemical reactions that
produce water as end products
 water leaves the body by several exits

•
•
•
•
the
the
the
the
kidneys excrete urine
lungs give of water in expired air
skin gives off sweat
intestines eliminate water in feces
 in general terms, the amount of water exiting the
body equals the amount entering the body

Electrolyte balance
 the quantities of various electrolytes taken into the
body must equal the quantities lost by the body
 in the extracellular fluid, two types of ions can be
found
 Cations: which are positively charged (sodium Na+)
 Anions: which are negatively charged (chloride Cl-)
 Sodium
Ions
 sodium ions account for about 90% of the cations
in extracellular fluid
 when the input of sodium ions exceeds the output,
water is also retained in the body, and the volume
of plasma and extracellular fluid Increases
 may cause edema: an abnormal accumulation of fluid
in extracellular body tissues
 may also cause weight gain
 when the output exceeds the input a decrease occurs
in the volume of plasma and extracellular fluid, and
the blood pressure lowers
 Regulation of sodium levels
 reflects how well the kidney is working and is affected
by blood pressure
 when the blood pressure drops, the blood flow to the
kidney is reduced, and the filtration rate diminishes,
resulting in less sodium filtered
 as the concentration of salt and water increases, the
blood pressure elevates and the sodium excretion
increases

Potassium
 Potassium is the primary intracellular cation
 It functions in regulating the electrical activity of
the muscle and nerve tissue
 In the extracellular fluid, potassium influences the
balance of acid and base
 Excessive potassium can cause fibrillations of the
heart
 Deficits of potassium can cause arrhythmia of the
heart

Other ions
 Other ions balanced in the body are calcium,
magnesium, sulfate, chloride phosphate, and
bicarbonate
 Calcium ions have roles in blood clot formation,
muscle contraction, hormonal activity, nerve
conduction, and as structural components of teeth
and bones
 The most common extracellular anion is chloride,
which is almost always linked to sodium

Acid/Base balance
 The balance of acids and bases in the body is
associated with the regulation of the hydrogen
ion concentration in the body fluids
 This concentration, expressed as ph, influences
the activity of cell enzymes as well as
maintenance of cell structural and cell membrane
permeability
 A strong acid produces the maximum number of
hydrogen ions possible and forms ions more
completely than weak acids
 hydrochloric acid is a strong acid
 carbonic acid is a weak acid
 There are many sources of hydrogen ions in the
metabolism of the body
 during the respiration of glucose, carbon dioxide
reacts with water to form carbonic acid which
dissociates to release bicarbonate ions and hydrogen
ions
 the breakdown of fatty acids and amino acids also
results in acid compounds


The regulation of the concentration of hydrogen ions in
the body occurs primarily by acid base buffer systems
Acid/Base buffer system
 A buffer is a solution that prevents substantial
changes in the pH when either an acid or a base
enters the system
 Usually a buffer system contains a carbonic acid
and a salt of that acid.
 an example is the carbonic acid and sodium
bicarbonate system
 A solution containing both carbonic acid and sodium
bicarbonate
 Should a strong acid such as hydrochloric acid enter
the system, it will react with the bicarbonate ions of
the sodium bicarbonate producing carbonic acid and
sodium chloride
 Carbonic acid is a weaker acid than hydrochloric acid,
and therefore the increase in hydrogen ions in the
solution will be minimal
 If a strong base such as sodium hydroxide enters the
solution it will react with the carbonic acid to produce
sodium bicarbonate a weaker base than sodium
hydroxide, and there will be a minimum base shift

Primary function: regulates the composition
and concentration of the extracellular fluids
surrounding the body cells
 extracellular fluids
 known as interstitial fluids
 include plasma and fluids surrounding tissue
 The urinary system accomplishes its functions by
forming urine from blood plasma in the kidneys
and associated ducts and organs

Location
 The kidneys are attached to the posterior
abdominal wall of the body outside the peritoneum
 They lie lateral to the vertebral column and are held
in place by adipose and connective tissue
 Adipose tissue is fatty tissue that surrounds internal
organs
 Adipose tissue serves as a cushion and as a nutrient
reserve
 In an adult each kidney weighs about 4 oz and is
about the size of a fist

Microscopic structure
 More than a million microscopic units called
nephrons make up the interior of each kidney
 The purpose of these nephrons is the production of
urine
 A nephron looks like a tiny funnel with a very long
stem

Kidney function
 Regulates the volume of blood plasma and thereby
contributes to blood pressure
 Controls the concentration of waste products in the
blood
 Regulates the concentration of the plasma‘s
electrolytes
 Contributes to the acid/base level of the plasma

The kidneys 2 million or more nephrons form
urine by a series of 3 processes
 Filtration of water and other dissolved substances
out of the blood
 Reabsorption of water and other dissolved
substances needed by the body back into the blood
 Secretion of waste molecules and excess ions into
the urine
Once urine has formed it drains out of each
kidney and down the ureter into the urinary
bladder
 To leave the body, urine passes from the
bladder down the urethra and out its external
opening
