Intro To Physiology Flashcards
What is the difference between intracellular and extracellular fluids?
Intracellular fluid is inside the cell whereas extracellular fluid is outside the cell
What are the components of extracellular fluid?
Blood plasma and interstitial fluid
Interstitial fluid is the fluid found outside blood vessels that surrounds cells
Why do females have a lower % of body water?
Females have more adipose tissue. Fat cells contain less water therefore leading to lower % of body water
What is osmolality and why is it important to maintain?
Osmolality is the total concentration of all particles free in a solution. It is important to maintain to avoid water moving in and out of a cell unnecessarily
What molecule affect osmolality?
Glucose
Ions
What separates blood plasma from interstitial fluid?
Capillary endothelium
What separates the interstitial fluid from the intracellular fluid?
Cell (plasma) membrane
What is the cell (plasma) membrane?
It is a phospholipid bilayer made of amphipathic molecules. This means it contains both hydrophobic and hydrophilic components
Can you briefly describe the structure of the cell membrane ?
The cell membrane has a hydrophilic head (likes water) and a hydrophobic tail (doesn’t like water). The heads face the ECF and ICF
What affect does cholesterol have on the membrane?
Different phospholipids give the membrane different stiffnesses and permeability. Cholesterol makes the membrane more stiff
What is the permeability of the cell membrane like?
The cell membrane has selective permeability meaning it only allows certain molecules to cross.
It is impermeable to large molecules such as proteins, charged, water soluble substances like ions. It is permeable to hydrophobic molecules like O2, CO2. Finally, it is partially permeable to uncharged, polar molecules
How can things move in and out if they can’t move through the membrane?
We can use membrane proteins which allow polar molecules like ions and sugars to pass through the membrane. These molecules can avoid the hydrophobic core of the phospholipid bilayer
What are vital parameters and give some examples?
Things that we must regulate such as glucose and ion levels in intracellular environments, plasma levels of oxygen and electrolytes in extracellular environment as well as whole body arterial pressure, blood volume and temperature
How can we maintain the vital parameters?
We can maintain a steady state of the vital parameters by homeostasis.
What is a negative feedback loop?
A negative feedback loop is physiological adjustment in the opposite direction that ensures homeostasis is maintained
