click below
click below
Normal Size Small Size show me how
101 Patho Exam 2
topics on Patho exam 2
Question | Answer |
---|---|
Atrophy | decrease in size of cell or tissue |
What causes atrophy? | decrease workload, pressure, use blood supply, nutrition, hormonal stimulation, nerve stimulation. as work of cell decreases, oxygen and nutrient requirements decrease. Cell and intracellular structures shrink. |
Physiologic atrophy | the impact of sedentary lifestyle, aging related to secondary sex organs and innervation with muscle and brain, and thrymus gland changes over time. |
examples of pathophysiologic atrophy | starvation resulting in reduction of fat and muscle cell size. Skeletal msucle after a car accident resulting in spinal cord transection. Disuse syndrome from immobilization, or in the space program, weightlessness |
What are changes over time that can occur in the brain from disuse atrophy? | Decrease nerve innervation and not enough oxygen and amino acid uptake is decreased, which is imoprtant in development in nonessential amino acids, which are essential and precursors to catacolines (dopamine etc..) It is pivital to brain function |
True or False? Dementia and depression can cause atrophy of the brain | True: Dementia and depression can cause brain atrophy. Social connectionn, crossword puzzles and such can keep this from happening. If you don't lose it you lose it! |
Hypertrophy | increase in the size of a cell or tissue when an increased workload or functional demand occurs. |
Is hypertrophy an increase in cell number or cell size? | Cell size |
In what cells are hypertrophy seen? | cells that cannot increase number of cells through mitosis: cardiac and smooth muscle. |
Why does hypertrophy occur? | as needs of the cell incrases for oxygen and nutrients, growth of the cell structures and cell occurs. |
example of physiologic hypertrophy | increased muscle bulk through exercise |
example of pathophysiological hypertrophy | cardiac muscle develops large left ventricle due to hypertension |
example of compensatory | following removal of a kidney, the remaining kidney enlarges to accommodate increased workload (in this case actually involves hyperplasia and hypertrophy) |
hyperplasia | increase in the NUMBER of cells resulting from an increased rate of cellular division. May occur following an injury, or in response to cytokine stimulation (growth factors) |
keloids | scar tissue (overgrowth due to fibroblast production of collagen) |
examples of physiologic hyperplasia | liver disease results in hepatocyte hyperplasia and regeneration of the liver. In a bone fracture, osteoblasts synthesize collagen and matrix to form a callus over the injury, with presure on your foot form a new shoe, a callus forms in response |
Hormonal hyperplasia | seen in uterus and breast tissue with pregnancy. |
examples of hyperplasia | seen in endometriosis (oversecretion of estrogen) and excessive menstual bleeding. Also individuals with a genetic predisposition form keloids following injury/surgery involving the epidermal layer of the skin. |
metaplasia | replacement of one mature cell type by another mature cell type. |
why does metaplasia occur? | it is an adaptive process in response to cellular injury or insult. usually a reversible condition if the stressor is removed. |
example of pathological metaplasia | normal columnar ciliated epithelial cells replaced by stratified squamous epithelial cells in bronchial lining with smoking |
dysplasia | abnormal changes in the size, shape and organization of mature cells. a pre-malignant condition of clinical significance |
pathological characterics of dysplasia | increased cell number secondary to increased mitosis and possibly reduced cell death due to apoptosis. |
nuclear abnormalities of dysplasia | may include altered nuclear size and shape, increased uptake of cell staining. |
common sites of dysplasia | include cervix due to human papilloma virus (HPV), and the bronchus due to smoking, tips of ears and nose due to sun exposure. |
test performed on sites of dysplasia | biopsy to examine cells under microscope |
ubiquitin | protein gets turned off and cells don't die, cells with the most tags die. |
Cellular aging | goes hand in hand wtih normal aging. cells get weaker and weaker because replicating so much. when cells are replicated so much there is a chance that mutation is occuring. |