Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
27 Cards in this Set
- Front
- Back
Homeostasis
|
Maintenance of a stable internal environment
|
|
Dynamic Equilibrium
|
Fluctuations of a parameter around a set point
|
|
Autoregulation
|
No nervous or endocrine input
Ex. Vasodilation of hypoxic tissues |
|
Extrinsic Regulation
|
Requires nervous or endocrine input.
1) Receptors 2) Integrator 3) Effectors Ex. Raise body temperature. 1) Thermoreceptors 2) Hypothalamus 3) Sweat glands, peripheral arteries dilate |
|
Positive Feedback
|
Effectors increase initial stimulus.
Ex. Childbirth: Baroreceptors on cervix stimulate oxytocin, which causes uterine contractions. |
|
Negative Feedback
|
Effectors oppose stimulus
|
|
Intracellular Fluid (ICF)
|
2/3 of total body water
|
|
Extracellular Fluid (ECF)
|
1/3 of total body water. Also: blood, lymph, serous fluid, synovial fluid, etc.
|
|
Interstitial Fluid
|
Fluid around cells. 3/4 of ECF.
|
|
Dehydration
|
- Decrease in water
- Increase in sodium - Hypernatremia (too much sodium in ECF) - Hypertonic ECF - Water exits the cell (crenation) |
|
Water Intoxication
|
- Hyponatremia (too little sodium in the ECF)
- Increase in water - Decrease in sodium - Hypotonic ECF - Water enters cell - lysis |
|
Sodium (Electrolyte Imbalance)
|
Hypernatremia: Increase electrochemical gradient of sodium to move into cell. Increase rate of action potential.
Hyponatremia: Decrease electrochemical gradient of sodium. Decrease rate of action potential. |
|
Potassium (Electrolyte Imbalance)
|
Hyperkalemia: Decreases gradient for potassium to leave cell. Difficulty repolarizing. Increases the rate of action potential.
Hypokalemia: Increases gradient for potassium to leave the cell. Decreases gradient for sodium to enter cell. Decreases rate of action potential. |
|
Calcium (Electrolyte Imbalance)
|
Hypercalcemia: Increase threshold of voltage-gated channels. Decrease rate of action potentials.
Hypocalcemia: Decrease threshold. Increase rate of action potentials. |
|
Acid-Base Balance
|
pH (power of hydrogen): Measure of hydrogen ions in solution.
Usually 7.35 - 7.45 > 7.45 = alkalosis < 7.35 = acidosis |
|
Renal Compensation
|
- If ECF is acidic, then secrete more hydrogen ions and reabsorb more HCO3-
- If ECF is alkaline, then reabsorb more hydrogen ions and secrete more HCO3- |
|
Buffer Systems
|
Work by accepting or donating a hydrogen ion. Ex. Protein buffer system, hemoglobin buffer system, phosphate buffer system, bicarbonate buffer system.
(Review buffer systems) |
|
Respiratory Acidosis
|
- Caused by hypoventilation (not breathing)
- Fixed by hyperventilating (respiratory compensation) - Renal compensation: Reabsorb more bicarbonate to bind to free hydrogen ions, secrete hydrogen ions |
|
Respiratory Alkalosis
|
- Caused by hyperventilation
- Fixed by hypoventilating (respiratory compensation) - Renal compensation: Secrete HCO3- , reabsorb hydrogen ions to bind to excess HCO3- |
|
Metabolic Acidosis
|
- Impaired renal function
- Lactic acidosis - Ketoacidosis: From breaking down structural proteins for energy - Fixed by hyperventilation - Renal compensation: HCO3- reabsorbed, hydrogen ions secreted |
|
Metabolic Alkalosis
|
- Caused by repeated, profuse vomiting
- Fixed by hyperventilation - Renal compensation: Secrete HCO3- , reabsorb hydrogen ions |
|
Types of Cellular Communication in Endocrine System
|
- Neural communication: Involves neurotransmitters
- Direct cellular contact: Gap junctions - Endocrine communication: takes longer to have effects, longer lasting effects - Paracrine communication: Uses paracrine factors (same molecules as hormones, but stay in tissue of origin) |
|
Categories of Hormones
|
- Amino acid derivatives
- Peptide hormones - Glycoproteins - Lipid derivatives - Eicosanoids |
|
Amino Acid Derivatives
|
Catecholamines (epinephrine, norepinephrine, dopamine), thyroid hormones, pineal hormones
|
|
Peptide Hormones
|
Loner chains of amino acids
Ex. Hypothalamic hormones, some anterior and posterior pituitary hormones |
|
Glycoproteins
|
Peptides with carbohydrate group
Ex. Anterior pituitary hormones, erthroprotein |
|
Lipid derivatives
|
Cholesterol-based, steroids (testosterone, estrogen, etc.)
|