NR283 Pathophysiology Study Guide for Exam 1
Chapter 1: Intro to Pathology
1 & 2. Describe the cellular adaptations made in each of the following processes and their
causative factors: atrophy, hypertrophy, hyperplasia, dysplasia, and metaplasia
Atrophy- a decrease in the size of cells, resulting in a reduced tissue mass. Common
causes include reduced use of the tissue, insufficient nutrition, decreased neurologic
or hormonal stimulation, and aging
Hypertrophy- an increase in the size of individual cells, resulting in an enlarged
tissue mass. This increase may be caused by additional work by the tissue, as
demonstrated by an enlarged heart muscle resulting from increased demands
Hyperplasia- an increased number of cells resulting in an enlarged tissue mass.
Hyperplasia may be a compensatory mechanism to meet increased demands, or
pathologic when there is a hormonal imbalance, or it may mean there is an increased
risk of cancer
Dysplasia- tissue in which the cells vary in size and shape, large nuclei are
frequently present, and the rate of mitosis is increased. May result from chronic
irritation infection, or may be a precancerous change. Detection of dysplasia is the
basis of routine screening tests for atypical cells such as the Pap smear
Metaplasia- when one mature cell type is replaced by a different mature cell type.
May result from a deficit of vitamin A. Metaplasia is sometimes an adaptive
mechanism that provides a more resistant tissue (i.e. when stratified squamous
epithelium replaces ciliated columnar epithelium in the respiratory tracts of cigarette
, smokers. The new cells make a stronger barrier but they decrease defenses for the
lungs because they lack cilia)
3. Identify the most common cause of cellular injury.
The most common cause of cellular injury is ischemia (decreased supply of
oxygenated blood to a tissue or organ, due to circulatory obstruction), which results
in hypoxia (reduced oxygen in tissue) and reduced cellular metabolism
Other causes of cell injury:
● Physical agents - excessive health or cold or radiation exposure
● Mechanical damage such as pressure or tearing of tissue
● Chemical toxins
● Microorganisms such as bacteria, viruses, and parasites
● Abnormal metabolites accumulation in cells
● Nutritional deficits
● Imbalance of fluids or electrolytes
4. Describe cellular injury caused by infection and inflammation.
Infectious diseases cause cell injury through microorganisms (i.e. bacteria &
viruses). Some microorganisms induce pyroptosis (a type of cell death by
lysis/dissolution of the cell), resulting in the rupture of the plasma membrane and
release of destructive lysosomal enzymes into the tissue, which causes inflammation
(swelling, redness, and pain) as well as damage to nearby cells and reduced function
,5. Describe the major mechanism of tissue damage caused by chemical injury.
Chemicals from both the environment (exogenous) and inside the body
(endogenous) may damage cells, either by altering cell membrane permeability or
producing free radicals, which continue to damage cell components
6. Discuss the manifestations of the four major types of necrosis, and give examples of the
tissue types affected by each type of necrosis.
Liquefaction necrosis- the process by which dead cells liquefy under the influence
of certain cell enzymes. Occurs when brain tissue dies, or in some bacterial
infections in which a cavity or ulcer develops in the infected area
Coagulative necrosis- when the cell proteins are altered or denatured and the cells
retain some form for a time after death. Occurs in a myocardial infarction when a
lack of oxygen causes cell death
Fat necrosis- when fatty tissue is broken down into fatty acids in the presence of
infection or certain enzymes. These compounds may increase inflammation.
Caseous necrosis- a form of coagulation necrosis in which a thick, yellowish,
“cheesy” substance forms. When TB develops, the first stage is characterized by
development of a Ghon complex a.k.a. granuloma (small solid mass of macrophages
& lymphocytes covered by connective tissue). Caseous necrosis can be seen inside
this mass. The Ghon complex heals like a scar, containing the infection. If the
infection continues to develop, the area may undergo liquefaction necrosis, forming
a cavity
, 7. Discuss apoptosis.
Apoptosis- programmed cell death; a normal occurrence in the body. Cells self-
destruct by digesting themselves enzymatically and then disintegrate into apoptotic
bodies (vesicles), which are then phagocized without eliciting an inflammatory
response. Apoptosis may increase when cell development is abnormal, cell numbers
are excessive, or cells are injured or aged.
8. Discuss the types of tissue necrosis.
Coagulative
o Cardiac
o Kidney caused by ischemia
Fat
o Pancreas
o Breast tissue
Liquefactive
o Abscess and hypoxic death
o Commonly found in the brain
Caseous
o Spaces of cavitation (cystic spaces)
o Found in TB patients and the bronchi
o Lungs, kidney
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller HIGHSCORE. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $15.49. You're not tied to anything after your purchase.
