Introductory Material Flashcards
Define anatomy and physiology
Anatomy- Structure of Body
Physiology- Function of Body
Name the different levels of structural organization that make up the human body and explain their relationships to each other.
Chemical
Molecular
Cellular
Tissue
Organ
Organ system
Organismal
List the physiological systems of the body, their major organs, and their functions
Integumentary
Skeletal
Muscular
Immune/Lymphatic
Digestive
Reproductive
Cardiovascular
Urinary
Respiratory
Endocrine
Nervous
Define homeostasis and explain its importance.
The ability to maintain a relatively constant internal environment, despite any changes in the external environment
When homeostasis is disrupted, illness – and potentially death – can be the result.
Local Control (Autocrine)
Cell acting chemically on itself.
Local Control (Paracrine)
Cell acting chemically on close by cell.
Long Distance/Reflex Control (Endocrine)
structure acting chemically on
other structures faraway
Long Distance/Reflex Control (Nervous)
structure acting chemically or electrically on other
structures far
Reflex Components
Stimulus
Detector/receptor
Input signal
Integrating center
Output signal
Target
Response
Negative feedback
Response reduces or eliminates original stimulus
Positive feedback
Response enhances original stimulus
Mass Balance
Amount of substance ”X” in body
= Amount taken in + amount produced – amount excreted – amount used (metabolism)
Extracellular Compartment
Two compartments
Interstitial fluid
Found around/between cells
Plasma
Liquid portion of blood
Higher in Na+
Higher in Cl-
Higher in Ca++
Plasma is higher in protein than interstitial fluid, which has very low protein levels
Intracellular Compartment
Also called cytosol
Higher in K+
Higher in Mg++
Higher in HPO4-
Higher in SO4-
Contains proteins
Compare and contrast the ICF and ECF , including relative
ion concentrations
The ICF is fluid in the cell , high in potassium ,hydrogen phosphate
The ECF is fluid outside of the cell , with subcompartments
interstitial fluid and plasma thigh in proteins).
The ECF is
high in calcium ,
sodium , and chlorine.
Membrane transport
movement of substances from one side of a membrane to the other.
Passive Transport
Does not use energy/ATP
Always involves movement of a substance down its concentration gradient
Diffusion
Simple diffusion
Facilitated diffusion
Osmosis
Factors that Affect Diffusion Rate
Molecular Size
Lipid Solubility
Surface Area
Membrane Thickness
Concentration Gradient
Temperature
Effect of increasing factor on diffusion rate
Molecular Size – decrease
Lipid Solubility - increase
Surface Area - increase
Membrane Thickness - decrease
Concentration Gradient - increase
Temperature - increase
Active Transport
Active transport always involves use of energy/ATP
Primary (1o) active transport
Uses ATP directly
Secondary (2o) active transport
Uses ATP indirectly
Moving vesicles within cell
Moving substances across cell membranes
Membrane carriers and pumps
Endocytosis and exocytosis of vesicles
Peripheral
attached to the extracellular face or intracellular face of the membrane
Integral
embedded in plasma membrane
Channels
open to both sides at once
Carriers
open to only one side at a time
Receptors
Send signals in response to ligand binding
Receptors can also be channels
Membrane Channels
Open/leaky
Gated
Ligand gated (receptor channels)
Mechanically gated
Voltage gated
Membrane Receptors
Channel receptors
Integrin receptors
Enzyme-linked receptors
G protein-coupled receptors
Membrane Potential
Separation of charges
Polarized (like a battery)
Dependent on
Ion concentrations (inside/outside cell)
Membrane permeability to ions
Channels
Carriers
Factors Affecting Ion Movement
Permeability of membranes to ion
Concentration gradient of ion
Electrical gradient
How will the membrane potential change if:
Sodium ions (Na+) enter the cell?
Positive charges enter the cell
Intracellular fluid (ICF) was -70mV compared to the interstitial fluid
ICF becomes more positive (-60mV, -50mV, -40mV, etc.)
As the inside becomes more like the outside, there is less separation of charge; the membrane potential is decreased (even though the number is becoming more positive)
Called depolarization
How will the membrane potential change if:
Chloride ions (Cl-) enter the cell?
Negative charges enter the cell
ICF becomes more negative
If starting at resting membrane potential
Hyperpolarization
If starting from a depolarized state
Repolarization
Action Potentials (APs)
A rapid change in membrane potential that is propagated along the membrane of an excitable cell
Electrical signal
Requires voltage gated channels to propagate it
Na+ and K+ channels
Refractory Period
This period ensures action potentials only travel in one direction out from the origin (not backwards)
Absolute refractory period
Na+ inactivation gates closed
Impossible for a new AP to start
Prevents “circular” signaling
Relative refractory period
Strong stimulus could lead to AP
