Chapter 6 Pathophysiology Flashcards
Epithelial tissue
- lines hollow organs within the body
- provides a protective barrier
- plays roles in the absorption of nutrients in the intestines and secretion of various body substances
Connective tissue
- binds other types of tissues together
- bone and cartilage are subtypes of connective tissue
- Adipose tissue is a special type of connective tissue that contains large amounts of lipids (fat)
Extracellular matrix
- nonliving substance consisting of protein fibers, nonfibrous protein, and fluid that separates connective tissue cells from one another
- collagen is the major protein within the extracellular matrix
Muscle tissue
-characterized by its ability to contract
-enclosed by fascia
-structually, stirated or nonstirated (also called smooth)
-functionally, voluntary or involuntary
3 types: skeletal (stirated, voluntary)
cardiac (stirated, involuntary)
smooth (nonstirated, involuntary)
Nerve tissue
-transmits nerve impulses
Axons
conducts electrical impulses away from the cell
Dendrites
receive electrical impulses from the axons of other nerve cells and conduct them toward the cell body
Synapse
the gap that separates nerve cells
Cell signaling
process by which cells communicate electrochemically
Ligands
molecules that bind to any receptor, leading to any reaction
-common ligands are hormones, neurotransmitters and electrolytes
Atrophy
decrease in cell size
Hypertrophy
increase in size of cells
Hyperplasia
increase in number of cells
Dysplasia
alteration in form
Metaplasia
refers to the reversible, cellular adaptation in which one adult cell type is replaced by another adult cell type (cancer)
Plasma
- 55% of blood
- composed of 91% water, and 9% plasma proteins
Plasma proteins include (4)
- albumin (maintains osmotic pressure)
- globulin
- fibrinogen
- prothrombin (assists during clotting)
Edema
- occurs when excess fluid builds up in the interstitial space
- peripheral edema is the most common
Ascites
abnormal accumulation of fluid in the peritoneal cavity
Edema causes
- increased capillary pressure
- decreased colloidal osmotic pressure in the capillaries
- decreased production of plasma proteins
- lymphatic vessel obstruction due to infection
3 types of receptors that monitors the body’s state of hydration
- osmoreceptors, monitor extracellular fluid osmolarity
- volume-sensitive receptors, located in the atria
- baroreceptors, found primarily in the carotid artery, aorta, and kidneys
Sodium is regulated primarily by
Renin-angiotensin-aldosterone system (RAAS)
Renin
protein released by the kidneys into the bloodstream in response to changes in blood pressure, blood flow, the amount of sodium in the tubular fluid, and glomerular filtration rate
Angiotensin 2
- stimulates sodium resorption by the renal tubules
- responsible for stimulating the secretion of aldosterone
Aldosterone
acts on the kidneys to increase the reabsorption of sodium into the blood and enhance the elimination of potassium in the urine
Tonicity
refers to the tension exerted on a cell due to water movement across the cell membrane
when cells are placed in an isotonic solution
they neither shrink nor swell
when cells are placed in a hypertonic solution
water is pulled out of the cells and they shrink
when cells are placed in a hypotonic solution
they swell
isotonic fluid deficit
decrease in extracellular fluid with proportionate losses of sodium and water
isotonic fluid excess
proportionate increase in both sodium and water in the extracellular fluid compartment
hypertonic fluid deficit
excess body water loss without a proportionate sodium loss
hypotonic fluid deficit
excessive sodium loss with less water loss
Normal physiologic pH range
7.35 to 7.45
Buffers
molecules that modulate changes in pH
pH greater than 7.45 is called
alkalosis
pH less than 7.35 is called
acidosis
Kussmaul respirations
deep, rapid, sighing ventilations
Hypoxic injury
- common, and often deadly cause of cellular injury
- result from decreased amounts of oxygen in the air or loss of hemoglobin function, a decreased number of rbc’s, disease of the respiratory or cardiovascular system, or loss of cytochrome function
Free radicals
randomly attack cells and membranes to “steal back” missing electrons
Types of cell injuries
- hypoxia
- ischemia
- chemical
- infectious
- immunologic
- physical
- inflammatory
Virulence
measures the disease-causing ability of a micro-organism
Location of virus replication
inside the host cell
2 ways an abnormal gene may develop
- mutation of the gene during meiosis
- heredity
Apoptosis
- normal cell death
- die in well-defined clusters
- can be activated prematurely by pathologic factors
Simple necrosis
refers to areas of necrosis where the gross and microscopic tissue and some of the cells are recognizable
Derived necrosis
includes caseation necrosis, dry gangrene, fat necrosis, and liquefaction necrosis
Dry gangrene
invasion and putrefaction of necrotic tissue after the blood supply is compromised
caseation necrosis
loss of all features of the tissue and cells
Factors causing disease (4)
- genetic
- environmental
- age-related
- sex-associated
Studies of disease: definitions of incidence, prevalence and mortality
- incidence: frequency of disease occurance
- prevalence: number of cases in a particular population over time
- mortality: number of deaths from a disease in a given population
genetic risk
passed through generations by inheritance of a gene
familial tendency
cluster in family groups despite lack of evidence for heritable gene-associated abnormalities
Autosomal recessive
- pattern of inheritance that involves genes located on autosomes
- a person needs to inherit two copies of the gene to show the trait
Autosomal dominant
person only needs to inherit one copy of particular gene to show trait
hemolytic anemia:
increased destruction of red blood cells
hemochromatosis:
body absorbs more iron than it needs
gout:
abnormal accumulation of uric acid
perfusion:
delivery of oxygen and nutrients and removal of waters from the cells, organs, and tissues by the circulatory system
hypoperfusion:
occurs when the level of tissue perfusion decreases below normal
2 types of shock
Central: includes cardiogenic and obstructive
Peripheral: includes hypovolemic and distributive
cardiogenic shock:
heart cannot circulate enough blood to maintain adequate peripheral oxygen delivery
obstructive shock:
blood flow becomes blocked in the heart or vessels
hypovolemic shock:
circulating blood volume is unable to deliver adequate oxygen and nutrients to the body.
2 types:
- exogenous
- endogenous
distributive shock:
occurs when there is widespread dilation of the resistance vessels, the capacitance vessels, or both. The circulating blood volume then pools in the expanded vascular beds, and tissue perfusion decreases. 3 most common types: -anaphylactic -septic -neurogenic
multiple organ dysfunction syndrome (MODS):
- progressive condition usually characterized by concurrent failure of several organs
- mortality rate of 60%-90%
2 primary lymphoid tissues:
- bone marrow
- thymus gland
red bone marrow:
essential for formation of mature blood cells; it produces B lymphocytes
lymph:
thin, watery fluid that bathes the tissues of the body
mucosal-associated lymphoid tissue (MALT):
contain immune cells that are in a position to intercept pathogens before they reach the general circulation
5 types of leukocytes:
- basophils
- eosinophils
- neutrophils
- monocytes
- lymphocytes
mast cells:
play a role in allergic reactions, immunity, and wound healing
native immunity:
nonspecific cellular response that is the first line of defense against pathogens and is associated with the initial inflammatory response
acquired immunity:
method by which armies of cells respond to an immune stimulant when body is exposed to a foreign substance or disease and produces antibodies to that invader
hapten:
substance that normally does not stimulate an immune response but that can be combined with an antigen and, at a later time, initiate a specific antibody response on its own
immunoglobulins:
- antibodies secreted by B cells
- Y-shaped protein that bind only on a specific antigen
killer t cells:
destroy the antigen
helper t cells:
activate many immune cells
suppressor t cells:
suppress the activity of other lymphocytes so they do not destroy normal tissue
memory t cells:
remember the reaction for the next time it is needed
chemotaxins:
attract leukocytes from the circulation to help fight the infection
fibrin:
protein that bonds to form a blood clot
cellular event sequence
- margination
- activation
- adhesion
- transmigration
- chemotaxis
cytokines:
products of cells that affect the function of other cells
interleukins:
attract white blood cells to the sites of injury and invasion
interferon:
protein produced by cells when invaded by viruses
function of lymphokines
stimulate leukocytes
4 steps of wound healing
- repair of damaged tissue
- removal of inflammatory debris
- restoration of tissues
- regeneration of cells
labile cells:
divide continuously, so organs derived from these cells heal completely
stable cells:
replaced by regeneration from remaining cells, which are stimulated to enter mitosis
permanent cells:
cannot be replaced, scar tissue is laid down instead
4 types of hypersensitivity reactions
type 1- an acute reaction that occurs in response to a stimulus
type 2- are cytotoxic and classically involve the combination of IgG or IgM antibodies with antigens on the cell membrane
type 3- involve primarily IgG antibodies that form immune complexes with antigen to recruit phagocytic cells, to a site where they can release inflammatory cytokines
type 4- allergic responses, also known as cell-mediated hypersensitivity, are primarily mediated by soluble molecules that are released by specifically activated T cells
Rh factor:
- antigen that is present in the red blood cells
- blood types are based on the presence or absence of these specific antigens
general adaptation syndrome: 3 stages
-introduced by Hans Selye in the 1920s
-characterizes a 3 stage reaction to stressors, both physical and emotional
Stage 1: Alarm
Stage 2: Resistance
Stage 3: Exhaustion
