Chapter 3 Cellular Adaptation, Injury, and Death
Tuesday, August 13, 2024 9:37 PM
1. Compare/contrast these ways that cells change (adapt) to improve their efficiency; (Discuss what
happens, when and/or why it happens, and how (or if) the adaptation makes the cell more
resilient)
○ Atrophy
○ What happens
▪ Atrophy is the decrease in cell size due to a reduction in the demand or
resources available to the cell
▪ The cell reduces its size and function to conserve energy and resources
○ When/why it happens
▪ Disuse
□ Cels shrink when they aren't used, such as in muscles during prolonged
bed rest or immobilization
▪ Loss of nerve supply
○ Hypertrophy
2. Describe two types of atrophy; provide examples
• When confronted with A decrease in work demand or adverse environmental conditions
cells are able to revert to a smaller size and a lower and more efficient level of functioning
○ This degree in cell size is called atrophy
• Atrophied cells reduce the size of their organelles and the number of their organelles, and
therefore reduce oxygen consumption and other cellular functions
○ When enough cells undergo atrophy and entire tissue atrophies
• General causes of atrophy
○ Disuse
▪ Occurs when there is a reduction in skeletal muscle use
□ Patient on a ventilator
□ Prolonged immobility
▪ Example is muscle loss because of extremities being placed in casts
○ Denervation
▪ This kind of atrophy occurs in the muscles of paralyzed limbs
□ Happens often after a spinal cord injury
○ Loss of endocrine stimulation
▪ In women, the loss of estrogen stimulation during menopause results and
atrophic changes in the reproductive organs
□ Breast and sex organ atrophy with prolonged decrease in estrogens (such
as associated with menopause)
▪ In men, testosterone abuse may lead to testicular atrophy
○ In adequate nutrition
▪ Sales must reduce their energy use and consumption to survive so they atrophy
▪ Ischemia or decreased blood flow
□ Increased blood flow cells are not getting the adequate nutrition that they
need in order to maintain a certain size so they shrink to the size that they
can maintain with the amount of blood flow they are receiving
• Advantages to Atrophy
○ Decrease in oxygen consumption
○ Fewer and smaller organelles to support
○ Fewer proteins are made which also decreases energy and resource use and demand
3. Describe two types of hypertrophy; provide examples
Nurse 395 Pathophysiology Page 1
, 3. Describe two types of hypertrophy; provide examples
• Hypertrophy represents an increase in cells size and often tissue mass
○ It is the result of an increased workload on an organ or body part
○ Easily seen in cardiac or skeletal muscle
▪ Muscle cells cannot undergo mitotic division so they grow instead of divide
• Hypertrophy can recur as pathological or physiological processes
○ Physiological
▪ Expected physiologic process that happens as a result of exercise or other
workload demands
▪ A physiological cause of hypertrophy is exercising, and as a result increased
muscle mass
○ Pathological
▪ Adaptive
□ Thickening of the urinary bladder do to outflow instruction
▪ Compensatory
□ Increase in the size of one kidney after the other is removed
□ Increase in size of liver as a result of donation to another
▪ A pathologic example of Hypertrophy is left ventricular hypertrophy because of
hypertension and increased stress on that area of the heart
• Initiating signals for Hypertrophy can be divided into two broad categories
• Biomechanical stress
• Neurohumoral Factors
4. Compare/contrast the "…plasias" on terms of what happens, usual causes, reversibility; provide
examples
○ Hyperplasia
• Hyperplasia refers to an increase in the number of cells in an organ or tissue
○ Occurs in cells that are capable of mitotic division
▪ Epidermis
▪ Intestinal epithelium
▪ Glandular tissue
• Hyperplasia involves activation of genes, controlling self proliferation, and the
presence of intracellular messengers, that control cell replication and growth
○ Hyperplasia is a controlled process that occurs in response to an appropriate
stimulus and ceases after the stimulus has been removed
• Types of physiological hyperplasia
○ Hormonal
▪ Breast and uterine enlargements during pregnancy as a result of estrogen
stimulation
○ Compensatory
▪ Regeneration of the liver that occurs after partial removal of the liver
▪ Development of callouses
• Hypertrophy and hyperplasia are two distinct processes, although they may occur
together and are often triggered by the same mechanism
• NonPhysiological hyperplasia
○ Excessive hormonal stimulation or the effects of growth factors on target tissues
▪ Excessive estrogen production can cause endometrial, hyperplasia, and
abnormal menstrual bleeding
▪ Skin wart, as the result of growth factors produced by viruses such as
papillomaviruses are an example of a non-physiological hyperplasia
○ Metaplasia
• Metaplasia represents a reversible change in which one adult cell type is replaced by
another adult cell type
○ Thought to involve reprogramming of undifferentiated stem cells
All types of metaplasia changes are considered to be precancerous changes
Nurse 395 Pathophysiology Page 2
Tuesday, August 13, 2024 9:37 PM
1. Compare/contrast these ways that cells change (adapt) to improve their efficiency; (Discuss what
happens, when and/or why it happens, and how (or if) the adaptation makes the cell more
resilient)
○ Atrophy
○ What happens
▪ Atrophy is the decrease in cell size due to a reduction in the demand or
resources available to the cell
▪ The cell reduces its size and function to conserve energy and resources
○ When/why it happens
▪ Disuse
□ Cels shrink when they aren't used, such as in muscles during prolonged
bed rest or immobilization
▪ Loss of nerve supply
○ Hypertrophy
2. Describe two types of atrophy; provide examples
• When confronted with A decrease in work demand or adverse environmental conditions
cells are able to revert to a smaller size and a lower and more efficient level of functioning
○ This degree in cell size is called atrophy
• Atrophied cells reduce the size of their organelles and the number of their organelles, and
therefore reduce oxygen consumption and other cellular functions
○ When enough cells undergo atrophy and entire tissue atrophies
• General causes of atrophy
○ Disuse
▪ Occurs when there is a reduction in skeletal muscle use
□ Patient on a ventilator
□ Prolonged immobility
▪ Example is muscle loss because of extremities being placed in casts
○ Denervation
▪ This kind of atrophy occurs in the muscles of paralyzed limbs
□ Happens often after a spinal cord injury
○ Loss of endocrine stimulation
▪ In women, the loss of estrogen stimulation during menopause results and
atrophic changes in the reproductive organs
□ Breast and sex organ atrophy with prolonged decrease in estrogens (such
as associated with menopause)
▪ In men, testosterone abuse may lead to testicular atrophy
○ In adequate nutrition
▪ Sales must reduce their energy use and consumption to survive so they atrophy
▪ Ischemia or decreased blood flow
□ Increased blood flow cells are not getting the adequate nutrition that they
need in order to maintain a certain size so they shrink to the size that they
can maintain with the amount of blood flow they are receiving
• Advantages to Atrophy
○ Decrease in oxygen consumption
○ Fewer and smaller organelles to support
○ Fewer proteins are made which also decreases energy and resource use and demand
3. Describe two types of hypertrophy; provide examples
Nurse 395 Pathophysiology Page 1
, 3. Describe two types of hypertrophy; provide examples
• Hypertrophy represents an increase in cells size and often tissue mass
○ It is the result of an increased workload on an organ or body part
○ Easily seen in cardiac or skeletal muscle
▪ Muscle cells cannot undergo mitotic division so they grow instead of divide
• Hypertrophy can recur as pathological or physiological processes
○ Physiological
▪ Expected physiologic process that happens as a result of exercise or other
workload demands
▪ A physiological cause of hypertrophy is exercising, and as a result increased
muscle mass
○ Pathological
▪ Adaptive
□ Thickening of the urinary bladder do to outflow instruction
▪ Compensatory
□ Increase in the size of one kidney after the other is removed
□ Increase in size of liver as a result of donation to another
▪ A pathologic example of Hypertrophy is left ventricular hypertrophy because of
hypertension and increased stress on that area of the heart
• Initiating signals for Hypertrophy can be divided into two broad categories
• Biomechanical stress
• Neurohumoral Factors
4. Compare/contrast the "…plasias" on terms of what happens, usual causes, reversibility; provide
examples
○ Hyperplasia
• Hyperplasia refers to an increase in the number of cells in an organ or tissue
○ Occurs in cells that are capable of mitotic division
▪ Epidermis
▪ Intestinal epithelium
▪ Glandular tissue
• Hyperplasia involves activation of genes, controlling self proliferation, and the
presence of intracellular messengers, that control cell replication and growth
○ Hyperplasia is a controlled process that occurs in response to an appropriate
stimulus and ceases after the stimulus has been removed
• Types of physiological hyperplasia
○ Hormonal
▪ Breast and uterine enlargements during pregnancy as a result of estrogen
stimulation
○ Compensatory
▪ Regeneration of the liver that occurs after partial removal of the liver
▪ Development of callouses
• Hypertrophy and hyperplasia are two distinct processes, although they may occur
together and are often triggered by the same mechanism
• NonPhysiological hyperplasia
○ Excessive hormonal stimulation or the effects of growth factors on target tissues
▪ Excessive estrogen production can cause endometrial, hyperplasia, and
abnormal menstrual bleeding
▪ Skin wart, as the result of growth factors produced by viruses such as
papillomaviruses are an example of a non-physiological hyperplasia
○ Metaplasia
• Metaplasia represents a reversible change in which one adult cell type is replaced by
another adult cell type
○ Thought to involve reprogramming of undifferentiated stem cells
All types of metaplasia changes are considered to be precancerous changes
Nurse 395 Pathophysiology Page 2
