Pathophysiology Flashcards
Pathophysiology
Study of the functioning of an organism in presence of disease
Cell
Basic self sustaining unit of the human body
Three Main Parts of Cell
Cell Membrane
Cytoplasm
Nucleus
Cell Membrane
Consists of fat and protein
-surrounds dell and protects nucleus and organelles
Organelles
Functional structure within the cells cytoplasm
Inside of Organelle
Ribosomes, ER, Golgi Complex, Lysosomes, Peroxisomes, Mitochondria, Nucleus
Ribosomes
Contain RNA and protein
- Responsible for controlling cellular activities
- interact with other amino chains to form proteins
- when attached to ER they for, rough ER
ER
Network of tubules, vesicles and sacs
- Smooth ER builds fats
- Rough builds proteins
Golgi Complex
Synthesis and packaging of various carbohydrates and complex protein molecules such as enzymes
Lysosomes
Membrane bound vesicles that contain digestive enzymes
-intracellular digestion that breaks down organic debris, (bacteria) that have been taken into the cell
Peroxisomes
Found in high concentrations in liver and neutralize toxins such as alcohol
Mitochondria
Metabolic center of cell no produce ATP, major energy source in the cell
Nucleus
Contains DNA in the chromosomes and RNA
Epithelium
Covers external surfaces and lines hollow organs such as intestines, blood vessels and bronchial tubes
- absorb nutrients
- secrete body substances (sweat)
Endothelial Cells
Epithelial cells that line vessels
-help regulate blood flow and have a role in blood clotting
Connective Tissue
Binds other types of tissue to one another
- separated by non living extracellular matrix consisting of protein fibers and fluid
- collagen main protein in fluid
- adipose tissue is a connective tissue mainly made of large amounts of lipids (fats)
- blood is connective
Muscle Tissue
Characterized by ability to contract -Enclosed by fascia, envelope of fibrous material Skeletal: striated volunTary Cardiac: striated involuntary Smooth: nonstriated involuntary
Nerve Tissue
Transmit nerve impulses
Central and Peripheral
Homeostasis
Same and steady
Apoptosis
Normal cell death in which old cells are replaced by new cells
Cell Signaling
Way that the cells communicate electrochemically to each other by releasing molecules (such as hormones) that bind to protein receptors on the cell surface.
In result, a triggered chemical reaction occurs and initiates a biological reaction
Baroreceptors
Respond to changes in pressure usually within heart or main arteries
Chemoreceptors
Sense changes in chemical composition of the blood, especially reduced oxygen levels and elevated CO levels
Five Primary Ways to Release Heat
Convection, conduction, evaporation, radiation and respiration
Ligand
“To tie or bind”
Are molecules that bind to receptor sites to form more complex structures
-Endogenous or Exogenous Ligands: produced by body or given into body
Hormones
Substances found in tiny amounts by one specialized group of cells and then carried to another organ or group of cells and then carried to another organ or group to perform regulatory functions
Endocrine Hormones
(Thyroid hormones and adrenal) carried to their target by the blood
Exocrine Hormone
Reach target by a specific duct that opens into an organ (stomach acids and perspiration)
Paracrine Hormones
(Histamines) diffuse through intracellular spaces to reach their target
Electrolytes
Dissolved mineral salts that dissociate in a solution yielding ions (sodium, potassium, clalcium, chloride)
-have important role in cell signaling and in generating the Nervous System action potential
Ions
Positive charge: cation
Negatively charged: anion
Body fluids are suppose to be electrically neutral
Atrophy
Decrease in cell size due to loss of sub cellular components which results in a decrease in the size of the organ or tissue
- actual number of cells remain unchanged but decrease in an attempt to cope with a new steady state
- coasted immobilized limb loses muscle and shrinks in size
Hypertrophy
Increase in the size of the cells due to synthesis of more subcellular components which creates an increase in size of a tissue or organ
-left ventricle may hypertrophy from increased pressure
Hyperplasia
Increase in actual number of cells in an organ or tissue usually resulting in increase in size of organ or tissue
-a callus is hyperplasia of the keratinized layer of the epidermis in response to increase friction or trauma
Dysplasia
Alteration of size shape and organization of cells is most often found in epithelial cells where they have undergone atypical, irregular inflammation or irritation.
-development of cervical dysplasia in women is strongly associated with exposure to certain viruses
Metaplasia
Reversible cellular adaptation in which one or more cell type is replaced by another adult cell type.
-the airway of smokers and cilia may be replaced by meta plastic epithelium after burned away
Body Weight
50-70% is fluid
Intracellular Fluid
75% of body weight in fluid
Extracellular Fluid
25% of body weight in fluid
- interstitial and intravascular
- interstitial: surrounds tissue cells and includes cerebrospinal, and synovial fluid
- intravascular: found within blood vessels but outside the cells
Solvent and Solute
Water and Salt
Passive Transport
Movement of substance by diffusion from area of high concentration to area of low concentration
Active Transport
Movement via transport molecules, or pumps, that require energy to move substances from an area of low concentration to area of high concentration
Osmosis - how water moves between ICF and EXF
Movement of a solvent from an area of low solute concentration to an area of high solute concentration through a selectively permeable membrane to equalize solute to solvent
Hypertonic Solution
Higher osmotic pressure due to having a higher solute concentration
Hypotonic Solution
Lower osmotic pressure due to having a lower solute concentration
Isotonic Solutions
Normal Saline e.g and lactate ringers
Intracellular Fluid controlled In two ways
By proteins and compounds that cannot escape and the sodium potassium pump
-most intracellular charges are negatively charged so they attract positively charged ions like potassium and because potassium is osmotically active, they can pull water into the cell. Even until it ruptures.
Sodium Potassium Pump
Responsible for checks and balances of water being brought in by continuously removing three sodium ions from the cell for every two potassium cells that are moved back into the cell
- if Pump is damaged due insufficient potassium, sodium accumulates and causes the cells to swell
- ATP used to make the exchange happen
Plasma
Makes up 55% of blood
91% water and 9% plasma proteins
-plasma proteins: albumin which maintains osmotic pressure; and fibrinogen and prothrombin which assist with clotting
Capillary Hydrostatic Pressure
Pushes water out of capillary into interstitial space. Cause pressures differ, more water is pushed out of arterial end and more is absorbed through venous end.
Tissue Colloidal Pressure
Draws fluid into the interstitial space
Edema
Occurs when excess fluid builds up in interstitial spaces -Many causes: increased capillary hydrostatic pressure from Allergic Reactions Venous Obstruction Increased vascular volume Increase adrenocorticol hormones Sodium retention Pregnancy Gravity from long sitting
ADH
Antidiuretic Hormone or “vasopressin”
RAAS
Renin-angiotensin-aldosterone system
- complex feedback mechanism responsible for kidneys regulation of sodium in the body
- high it is secreted, low it is reabsorbed
Osmoreceptors
Monitor extracellular fluid osmolarity
- located primarily in Hypothalmus
- when extrcellular osmolarity is too high they stimulate production of ADH