81 terms

Altered Cellular & Tissue Biology

EMSON UA Nursing
Stages in the Cellular Response to Stress and Injurious Stimuli
homeostasis, adaptation, cell injury/death
Normal Cell (Homeostasis) (change to next stage)
Stress, increased demand
Adaptation (change to next stage)
hypertrophy, hyperplasia, atrophy →Injurious stimulus/Inability to adapt
Cell injury/cell death: (change to next stage)
necrosis, apoptosis, pathologic calcification (calcium deposited at site of cell death)
Atrophy is a decrease in cell size due to:
Disuse/decrease workload, Denervation/loss of innervations (ex. Paralysis), Lack of endocrine stimulation (ex. Menopause results in a decrease in breast size), Decreased nutrition, Ischemia or decreased blood flow
Hypertrophy is an Increase in functional cell/tissue size due to
Physiologic hypertrophy, Adaptive hypertrophy, Compensatory hypertrophy
Physiologic hypertrophy,
ex. Hormone induced hypertrophy (uterus during pregnancy)
Adaptive hypertrophy
increase in cell size to accommodate changes
Compensatory hypertrophy
increase in size to compensate for loss (ex. Kidney will hypertrophy if the other one is removed)
Increase in cell number
The 3 types of hyperplasia:
Hormonal, Compensatory, Pathologic
Hormonal hyperplasia
ex. Breast growth during puberty
Compensatory hyperplasia
ex. Increase in red blood cells in response to high altitudes
Pathologic hyperplasia
ex. Increase in liver cells in response to alcoholism
Metaplasia is the...
Reversible replacement of one mature cell type by another (sometimes less differentiated)
Metaplasia maintains
cell lives
Metaplasia is survival...
of the fittest
Metaplasia can be...
good or bad
Metaplasia: Ex. Acid can change esophageal squamous cells to
glandular cells
Deranged cell growth
Dysplasia is abnormal changes in the
size, shape, and organization of mature cells
Dysplasia leads
to cancer
Dysplasia leads to Cellular
Injury and Death
programmed cell death
6 types of apoptosis:
Embryogenesis, involution, cell deletion, death of host cells, elimination of lymphocytes, cytotoxic T cells
Pathologic Apoptosis
apoptosis at wrong time
Cell death in an organ or tissue that is still a part of a living person
Pathologic conditions of necrosis
Cell death, cell injury, pathologic atrophy, tumors
4 Types of necrosis
Liquificative, infarction, coagulative, caseous
Liquificative necrosis-
brain and spinal cord
Infarction necrosis-
lack of blood supply
Coagulative necrosis -
common in kidneys
Caseous necrosis-
"cheesy-like" substance, associated with TB, decreased function
Common Causes of Injury and Death
toxin, infection, physical injury, serum deficit
3 types of Physical Injury
mechanical, chemical, thermal
3 causes of Serum deficit
nutrition, hydration, oxygenation
3 causes of Cell Injury and Death
Hypoxia, cell injury, anoxia
decreased oxygen
no oxygen
decreased blood flow
Chemical injury
A biochemical reaction between a toxic substance and the cell membrane leading to increased permeability
Effects of Hypoxia: Reduction in...
Na+ - K+ pump
Effects of Hypoxia: Na+ - Ca++
exchange fails
Effects of Hypoxia: Reduced ATP production leading to
cellular swelling as Na-K pump fails
Effects of Hypoxia:: Injury to lysosomal membranes results in
leakage of enzymes and self destruction
Poisons -
highly toxic chemical substances
3 popular poisons
Arsenic, Cyanide (naturally occurring in plants), Lead
Constitutes a high percentage of childhood poisonings
Malnutrition enhances
lead uptake
Lead causes
hyper activity in children, convulsion, delirium, peripheral nerve damage and paralysis, anemia (lysis of red blood cells)
Organs effected by lead poisoning: :
CNS, hematopoietic system, renal system, GI system
Renal lesion can cause
nausea, loss of appetite, weight loss, abdominal cramping
Carbon Monoxide:
Produces hypoxia
CO Takes over
respiratory system and hemoglobin\
CO Causes
giddiness, headache, hyperactivity, red skin
CO's Half life
3-4 hours
CO's Affinity for hemoglobin is
300x higher than oxygen
Ethanol consumption by pregnant women causes_________
Fetal Alcohol Syndrome
Fetal Alcohol Syndrome results in
Mental retardation, malformation, disfiguration
FAS can lead to
Microcephaly (small brain)
Unintentional/Intentional Injuries:
Blunt force injuries, contusion, Abrasion, Laceration, sharp force injuries, gunshot wounds, aspyxia, drowning
Blunt force injuries include
Tearing, shearing, crushing of tissues, Subdural (dura mater) hematoma (collection of fluid around brain)
A contusion is bleeding...
into skin or underlying tissues
Contusions are caused by...
Blows to head, fall, or impact
Contusions Cause __________ (collection of blood in tissues)
Epidural hematoma, caused by torn artery, associated with _____________
skull fracture
Tear or rip
Sharp force injuries
Incised, stab, puncture, chopping
Incised wounds
(length of cut greater than depth)
Stab wounds
(depth of cut is greater than length)
(made with blunt or dull object)
Chopping wounds
(blunt and sharp force)
Gunshot wounds (2 types)
Penetrate & perforate
(bullet gets stuck in body)
(bullet exits body)
Asphyxia (2 types)
Suffocation & strangulation
anything that blocks oxygen from blood
caused by compression of blood/airways
It takes __________ to close jugular vein
4.5 lb
It takes 11 lb to close ___________
carotid artery