Intro to Pathophys and Basic Cellular Physiology

Question 1

describe cell membrane composition

Answer 1

plasma membrane made up of phospholipid bilayer.

Question 2

describe the features of phospholipids that make them capable of forming the cell membrane.

Answer 2

phospholipids are amphipathic (one portion hydrophilic, one portion hydrophobic).

Question 3

what types of molecules can diffuse directly through the bilayer?

Answer 3

small, non-polar molecules

Question 4

discuss the difference between steady state and equilibrium.

Answer 4

equilibrium is a passive process by which opposing gradients provide drive for movement of solutes. a system in steady state remains constant but requires continual work (energy).

Question 5

describe how genetics can contribute to variations in normal

Answer 5

can predispose individuals to certain dieases

Question 6

describe how age can contribute to variations in normal

Answer 6

newborns have immature immunes systems and are susceptible to infection. elderly have decrease immune function and are more susceptible to infection.

Question 7

describe how stress can contribute to variations in normal

Answer 7

increases productions of steroid, decreases immune function

Question 8

pathophysiology

Answer 8

study of how disease processes work to cause dysfunction

Question 9

pathogenesis (discuss 3 stages)

Answer 9

development or creation of diseases

1. cause
2. abnormal function
3. manifestation: signs/symptoms, how disease manifests

Question 10

etiology

Answer 10

cause of disease OR study of the cause of diease

Question 11

describe metabolic disease in general terms

Answer 11

born with or genetic predisposition to disease. problem with anabolism or catabolism, results in loss of hemostasis

Question 12

describe congenital disease in general terms

Answer 12

base on an anomaly or defect present at birth

Question 13

describe degenerative/drug induced disease in general terms

Answer 13

change to a lower level of function due to use, drugs

Question 14

describe neoplastic disease in general terms

Answer 14

caused by malignant cell growth

Question 15

describe immunologic/autoimmune disease in general terms

Answer 15

the body mounting a defense against a threat, which is sometimes the body’s own tissue

Question 16

describe infectious/inflammatory disease in general terms

Answer 16

invasion of the body by disease-causing agents (causing rubor, dolor, tumor, calor, functio laesa)

Question 17

list the 5 signs and symptoms of inflammation

Answer 17

1. calor: heat
2. rubor: redness
3. tumor: swelling/edema
4. dolor: pain
5. functio laesa: loss of function

Question 18

describe nutritional disease in general terms

Answer 18

pertains to intake of vital substances for the growth and maintenance of the body

Question 19

describe genetic disease in general terms

Answer 19

disease caused by the phenotypic expression of genes. can be congenital or acquired.

Question 20

describe psychological/somatic disease in general terms

Answer 20

coming from within the mind, unable to be traced back to physical location

Question 21

describe iatrogenic disease in general terms

Answer 21

caused by treatment or diagnostic procedures

Question 22

idiopathic

Answer 22

unknown origin

Question 23

describe vascular disease in general terms

Answer 23

caused by the system which houses and transports blood through the body

Question 24

describe organic disease in general terms

Answer 24

grounded in the physical nature of the body, nothing we can test for, could be somatic, no known cause

Question 25

how does steady state help control cell volume?

Answer 25

cell volume changes depending on solute concentrations both in and out of the cell. steady state is continual work of both active and passive transport to maintain equilibrium. this often dictates a change in cell volume to account for solute concentrations both in and out of the cell.

Question 26

discuss diffusion

Answer 26

does not require energy. movement of molecules across membrane, depending on charge and size. efficient over short distances

Question 27

discuss facilitated diffusion

Answer 27

does not require energy. net flux is from high to low concentration. mediated by transport proteins that are specific for ligands. max rate of diffusion occurs at saturation

Question 28

primary active transport

Answer 28

requires energy, moves molecules against concentration gradient, utilizes hydrolysis of ATP as energy. transport protein required, proteins are specific for molecules

Question 29

secondary active transport

Answer 29

uses concentration gradient of Na+ to drive transport of a secondary molecule, indirectly requires ATP. requires escort molecule (e.g. Na+)

Question 30

tight junctions

Answer 30

trans-membrane proteins adhering to cell membranes of two adjacent epithelial cells. create barrier for molecule passage between cells

Question 31

apical membrane

Answer 31

faces lumen or duct

Question 32

basolateral membrane

Answer 32

faces interior of body

Question 33

discuss covalent modulation

Answer 33

change in receptor protein shape following chemical binding to the protein (e.g. phosphorylation)

Question 34

discuss allosteric modulation

Answer 34

change in receptor protein shape following binding of a modulator molecule.

Question 35

define signs

Answer 35

an objective finding by clinician, a sign of underlying disease

Question 36

define symptoms/symptom complexes

Answer 36

series of signs and symptoms grouped together without any consideration to their relationship to disease/illness

Question 37

syndrome

Answer 37

group of symptoms and signs indicative of an illness/disease

Question 38

describe the latent phase of disease

Answer 38

not active, cannot be seen. e.g. varicella zoster remains in nerve root gangion

Question 39

describe the incubation period of disease

Answer 39

period between exposure and development of signs and symptoms

Question 40

describe the prodrome period of disease

Answer 40

early symptom/sign that indicates onset of disease

Question 41

describe the acute phase of disease

Answer 41

sudden onset of signs and symptoms, short duration

Question 42

describe the subacute/subclinical phase of diease

Answer 42

somewhat rapid change, in between acute and chronic.

Question 43

describe the chronic phase of disease

Answer 43

gradual onset, insidious, longer than 6 months

Question 44

describe remission/reoccurrence of disease

Answer 44

temporary or permanent abatement of symptoms (remission). reoccurrence: symptoms/signs developing after remission.

Question 45

describe convalescnce

Answer 45

time spent recovering from an illness, medical treatment, or injury

Question 46

describe sequela (sequelae)

Answer 46

secondary conditions or illnesses, e.g. Kaposi's sarcoma, secondary to AIDS

Question 47

describe endogenous/exogenous as it pertains to causing disease

Answer 47

endogenous: internal cause or origin exogenous: caused by an agent outside of the body

Question 48

define epidemiology

Answer 48

study of the distribution, origin, and causes of disease within a community.

Question 49

where is the concentration of Na+ ions the greatest?

Answer 49

extracellular fluid

Question 50

where is the concentration of K+ ions the greatest?

Answer 50

intracellular fluid

Question 51

what is the energy transport mechanism that uses [Na+] to drive solute movement "uphill"?

Answer 51

secondary active transport

Question 52

explain Na+/glucose co-transport

Answer 52

small intestinal mucosa, Na+ moves down its concentration gradient into the cell brings glucose with it. glucose is moving up its concentration gradient.

Question 53

explain Na+/Ca2+ counter-transport/exchange

Answer 53

transport mechanism that uses Na+ gradient to move Ca2+ out of the cell by exchanging one Na+ into the cell for 3 Ca2+ ions out of the cell.

Question 54

in general, what is trancellular epithelial transport?

Answer 54

movement of molecules from luminal to basolateral sides of cell by traveling through cells

Question 55

what is paracellular transport and what is the limitation to this type of transport?

Answer 55

movement of molecules from luminal to basolateral sides of cell by traveling between cells. movement of molecules depends on size and the degree of space between adjacent cells that are connected by tight junctions

Question 56

what type of pump is always on the basolateral membrane and helps to establish the polarity of epithelial cells?

Answer 56

Na+/K+ ATPase pumps

Question 57

what type of transport is utilized by symporters/antiporters?

Answer 57

secondary active transport

Question 58

what is the difference between a symporter and an antiporter?

Answer 58

both are forms of secondary active transport. symporter moves two molecules across a membrane in the same direction, antiporters move two molecules across a membrane in opposite directions (e.g. one goes in, one goes out)

Question 59

what would happen to a cell placed in iso-osmotic solution?

Answer 59

volume stays the same, solution has the same solute concentration as intracellular environment

Question 60

what would happen to a cell placed in hypo-osmotic solution?

Answer 60

extracellular soution has a lower solute concentration than intracellular environment, the cell volume would increase as water flows into the cell

Question 61

what would happen to a cell placed in hyper-osmotic solution?

Answer 61

extracellular solution has a higher solute concentration than intracellular environment, the cell volume would decrease as water flows out of the cell

Question 62

what processes are involved in endocytosis

Answer 62

phagocytosis and pinocytosis

Question 63

give an example of how secondary transport (luminal) and facilitated diffusion (basolateral) can be used to move substance X across an epithelial cell

Answer 63

on the luminal side, Na+ concentration gradient is used to symport Na+ and X into the cell (down Na+ concentration gradient). on the basolateral side, facilitated diffusion (via protein channel that does NOT require energy) carries X out of the cell down it's concentration gradient.

Question 64

explain how Na+ is moved from luminal side to basolateral side via transcellular mechanisms.

Answer 64

Nat+ enters the cell via diffusion through Na+ channel (passive process, down concentration gradient). to exit the cell on the basolateral side, Na+ must go up its concentration gradient, which requires active transport (hydrolysis of ATP).

Question 65

how do endo and exocytosis play a role in cell membrane recycling?

Answer 65

pinching off portions of the membrane consistently to allow repair and replacement.

Question 66

discuss the process and location of action for lipid soluble first messengers

Answer 66

able to cross cell membranes. bind to receptors inside target cells, activated receptors act as transcription factors.

Question 67

discuss the process and location of action for water-soluble first messengers

Answer 67

bind to receptors on the plasma membrane. induces activation of secondary messengers.

Question 68

name two common second messengers that were discussed in our objectives

Answer 68

cAMP and Ca2+

Question 69

discuss the mechanism of Ca2+ as a second messenger

Answer 69

normal Ca2+ levels in the cytosol are low. binding of some hormones and signal molecules can cause spikes in intracellular Ca2+ levels. Ca2+ can bind to calmodulin which in turn activates or inhibits a variety of proteins. Ca2+ can also combine with other proteins (same basic mechanism as activation of calmodulin). Ca2+ can also combine with and directly alter response proteins.

Question 70

discuss the mechanism of cAMP as a second messenger

Answer 70

cAMP binds to cAMP dependent protein kinase (AKA protein kinase A or PKA), which then phosphorylates proteins downstream in the signal cascade.

Question 71

what are eicosanoids? how are they produced?

Answer 71

family of chemicals produced from arachidonic acid. 1. synthesis is activated by hormones, neurotransmitters, paracrine agents, drugs or toxic agents binding to appropriate membrane bound receptor 2. this activates phospholipase A2 to release arachidonic acid from the membrane phospholipids 3. arachidonic acid is either metabolized by cycloxygenase (produces prostaglandins and thromboxanes) or lipoxygenase (produces leukotrienes)

Question 72

what common drugs affect eicosanoid production?

Answer 72

1. aspirin (inhibits cyclooxygenase) stops production of prostaglandins and thromboxanes. 2. NAIDSs also inhibit cyclooxygenase 3. adrenal steroids are used in large doses as anti0inflammatory drugs and inactivate phospholipase A (therefore stopping production of ALL eicosanoids)