Cellular Adaptation and Damage - Module 1

what is cellular adaptation?

-method in which cells try to prevent their death from environmental changes

-modify in size, number, type

-normal or abnormal

-compensatory or hormonal

-permanent or reversible

what is atrophy?

decrease in size of cell to conserve energy and resources

what are examples of atrophy?

-limb in a cast/paralyzed limb

-brain in alzheimer's disease

-ovaries after menopause

what is hypertropy?

increase in the size of cells to meet increase work demand

what is a normal example of hypertrophy?

biceps after lifting weights

what is an abnormal example of hypertrophy?

left ventricle enlargement due to hypertension

what is hyperplasia?

increase in number of cells usually because of normal stimuli

what is a compensatory example of hyperplasia?

wound healing

what is a hormonal example of hyperplasia?

endometriosis; benign prostatic hyperplasia

what is dysplasia?

cells mutate into cells of different size, shape, and appearance; precancerous

what is an example of dysplasia?

cervical changes from human papilloma virus (HPV)

what is metaplasia?

one adult cell is replaced by another cell type because of chronic irritation and inflammation

what is an example of metaplasia?

Barret's esophagus

-esophagus exposed to stomach acid -> cells of esophagus (squamous) 'morph' to cells of intestine (columnar)

what is hypoxia?

lack of sufficient oxygen within cells/most common cause of cell injury

what is ischemia?

reduced supply of blood and therefore oxygen/most common cause of hypoxia

what is necrosis?

cell death due to injury/most common cause is ischemia

what is apoptosis?

programmed cell death/normal

-RBC= 120 days; skin=2-3 weeks; sperm=3 days

how do apoptosis and necrosis differ

apoptosis is normal, programmed cell death; while necrosis is cell death due to injury

name 2 ways hypoxia and ischemia differ

-ischemia is the reduced supply of blood; hypoxia is the lack of sufficient O2 within cells

-hypoxia causes ischemia

characteristics of benign cancer

-usually encapsulated with connective tissue

-do not invade lymph nodes or distant locations

-can become large

how is benign cancer named?

according to tissues from which arise with suffix 'oma'

fat cells- lipoma

smooth muscle of uterus - leiomyoma

characteristics of malignant cancer

-lack a capsule

-grow to invade nearby blood vessels, lymph nodes, surrounding structures

-metastasis -spread far beyond tissue of origin

-more rapid growth and loss of cellular differentiation (anaplasia)

-absence of normal tissue organization and have variability of size and shape

how is malignant cancer named?

named from cell type originate from

epithelial tissue - carcinoma

glandular or ductal - adenocarcinoma

lymphatic tissue - lymphoma

blood forming cells - leukemia