pathophysiology cell unit

pathophysiology

the study of the structural and functional characteristics in the cell, tissues, and organs of the body that cause or are caused by disease

homeostasis

the ability to respond to and maintain physiologic and psychological stability during rapidly changing conditions in the internal and external environment

adaptation

cell changes that occur to maintain homeostasis

semipermeable

some molecules can pass but others cannot

protein synthesis

transcription (transfer of genetic instructions) and translation (genetic instructions is read, correct amino acids are put in order, polypeptide forms)

ribosomes

protein synthesis to keep cells alive

golgi apparatus

flattened sacs that sorts, modifies, and packages proteins, transports in and out of cell through cell membrane

mitochondria

power (transform food to energy), site of cellular respiration

cellular metabolism

begins when food enters GI tract, aerobic and anaerobic

aerobic metabolism (Kreb’s cycle)

oxygen based, provides mitochondria with oxygen necessary to metabolize fats, proteins, and carbohydrates. CHO first, triglycerides second

anaerobic metabolism

used for energy when no energy is available, glucose based, uses glycolysis for temporary energy when O₂ supply is diminished, end product is lactic acid, glucose to ATP

lactic acid buildup causes

muscle pain and fatigue, metabolic acidosis, kidney failure, respiratory failure, and death

proliferation

cells divide / reproduce

prophase

the chromosomes condense and the nuclear membrane disintegrates

metaphase

the spindle fibers attach to centromeres and the chromosomes align

anaphase

the chromosomes separate and move to opposite poles

telophase

the chromosomes arrive at each pole and new membranes are formed

interphase

period of time between mitosis stages, cells spend most of lifetime in this stage

differentiation

process of specializing

stem cells

reserve cells with characteristics of a differentiated cell

tissues

groups of cells

loose CT

supports organs and blood vessels as well as connects epithelial tissue to muscle

dense CT

fibrous and found in the tendons and ligaments that connect muscles to bones and bones to each other

skeletal muscle

voluntary, striated, attach to bones and tendons

cardiac muscle

found in heart, striated, involuntary

smooth muscle

found in GI tract, blood vessels, uterus, and bladder, involuntary, not striated

dendrites

make connections with nearby cells and transmit impulses towards the cell body

axons

transmit impulses away from the cell body

schwann cells

type of neuroglia involved in speed of conduction, seen on myelinated tissue, can repair themselves

atrophy

decreased work, no stress present, cell decreases in size

hypertrophy

lots of work, excess stress present, cells increase in size (can be related to hormones)

hyperplasia

increase in normal cells, can be due to hormonal or external stimulation - important in wound healing

metaplasia

replacement of one cell by another cell type - usually within the same tissue type

dysplasia

rapid abnormal cell growth (mutation) - precursor to cancer, can be reversed if caught early and trigger is removed

apoptosis

structural cell changes that result in cell death

ischemia

inadequate blood flow to a tissue or organ

infarct

when ischemia causes irreversible damage

necrosis

cells get too big and burst

general adaptation syndrome

a cluster of systemic manifestations that represent an attempt to cope with a stressor

alarm (fight or flight)

hormones released (catecholamines and cortisol), generalized stimulation of the sympathetic nervous system

resistance phase

return to normal, facilitated by desensitization and relaxation

exhaustion phase

prolonged stress, depleted coping, can result in illness and death

immunosuppression

decreased function of immune cells

inflammatory response

damage or trauma to tissue

acute

immediately after injury, lasts hours to days. erythema - redness, edema, hot to touch, patient in pain

chronic

occurs if acute response does not solve the problem, has local and systemic effects, lasts weeks to months