Chapter 5 Flashcards
How much Intercellular fluid (ICF) makes up of total body water volume?
2/3
How much does extracellular fluid take up of total body water volume?
1/3
What are the two types of extracellular fluid?
1) Interstitial fluid which is the fluid between the circulatory system and the cell
2) Blood plasma which is the watery part of blood
What is the major molecule that can pass through cells and the matrix outside of it?
H2O
What is chemical disequilibrium?
In happens when there is a higher concentration of a solute in one part of the body than another
What is an example of chemical disequilibrium?
Potassium (K+) being more concentrated inside of the cell while Calcium is more concentrated outside of the cell
What is electrical disequilibrium?
Is when the charges of two different parts of the body are different from each other.
What is an example of electrical disequilibrium?
As a result of the chemical disequilibrium the inside of the cell has more a positive charge and the outside of the cell has more of a negative charge.
What are the 2 factors that affect the variation of body water in people?
The two main factors are age and sex. As infants we contain a significantly higher amount of body water than adults. Meanwhile, since women have more adipose tissue and men have more muscle tissue men have a higher amount of body water.
What does the variation of body water matter?
It is important because in clinical practice the amount of body water of the individual affects how much medication is needed for them to take. Since it would dangerous to give them the wrong amount for their size.
What is osmolarity?
It describes the amount of ions that are osmotically active per a liter of the specific solution
How can cells be in osmotic equilibrium but chemical and electrical disequilibrium?
Cells can be in osmotic equilibrium but chemical and electrical disequilibrium because osmotic equilibrium only takes into account if the amount of water is equal across different portions of the body
What does selectively permeable mean for the cell membrane?
It means that the membrane allows certain molecules to pass through easier than others based on the cells function and needs
How is passive transport different from active transport?
It is different because passive transport does not require energy other than the potential energy of the concentration gradient. Meanwhile, active transport requires extra energy from atp to allow for the molecule to pass through
What does protein mediated mean when it comes to cell transport?
It means the the protein that is embedded into the cell membrane is helping the ion or molecule to move across
What is the difference between facilitated diffusion and active transport?
Facilitated diffusion is when molecules move across the cell membrane with the help of membrane protein. Compared to active transport which needs energy from another source such as a ligand or atp
What does specificity mean when it comes to protein mediated transporters?
It refers to what kind of molecule the transporter will take and it will refuse to take others ex GLUT will not take disaccharides
What is an example of specificity?
In the GLUT family of transporters it will only move six carbon sugars or hexoses across the membrane such as galactose, mannose, or glucose. It will refuse to take any disaccharide or any other kind of glucose
What is GLUT?
A type of membrane protein that transports glucose
What does saturation mean in terms of protein mediated transporters?
It means that that transporter reaches the amount of stuff that it can carry because all of its binding sites are full
What is an example of saturation?
A GLUT transporter reaching its maximum capacity for carrying hexose sugars
What does competition mean in terms of protein mediated transporters?
It refers to when substrates of a similar kind are competing for a binding site
What is an example of competition?
GLUT transports move a group of hexose sugars but each transporter has a preference for its specific type of sugar such as mannose, or galactose.
What does transport maximum mean?
It is when the transporter has reached its maximum since all of the binding sites are full of substrate
What is an example of transport maximum?
A GLUT transporter reached its maximum capacity for carrying glucose
What is paracellular absorption across the epithelial membrane?
It is a type of absorption that occurs when materials are able to move through the tight junctions that are holding the cells together
What is vesicular transport (transcytosis)?
It is the epithelial membranes version of endocytosis, and vesicular transport. Because it membrane uses receptor mediated endocytosis to bring in a molecule (that would be too large to pass through on its own otherwise) where it gets transported though cells by a vesicle before getting released into the intertsitial fluid by exocytosis
What an example of why transcytosis is needed?
Because that is what allows for infants to absorb antibodies from the placenta before birth but mainly breastmilk
Is there a higher concentration of potassium inside of or outside of the cell?
Inside of the cell
Is there a higher concentration of sodium inside or outside of the cell?
Outside
Is there a higher concentration of chloride inside of or outside of the cell?
Outside
What is a concentration gradient?
It is a gradient that is made up of the amount of ions that are inside of or outside of a cell
What is electrical potential?
Electrical potential is the electrical charge from the inside and the outside of a cell. Which is affected by the amounts of ions and their locations
What is an electrochemical gradient?
It takes into account both the electrical and chemical gradients of ions inside and outside of the cell.
What does resting potential mean?
It is the resting potential is the charge that a cell has once its reached a steady state of ions and they are no longer adjusting their amounts
What contributes to the membrane potential of each cell?
What contributes to the membrane potential of each cell is the cells membrane permiablitly allowing moleucules in at the amounts that are needed
What does depolarizing mean in terms of membrane potential?
It is when the charge becomes less negative than would be at resting potential. (aka gets a little more postitive)
What does hyperpolarization mean?
It is when the charge gets more negative than it normally is at resting potential
What does repolarizing mean?
It is working to get the cell back to resting potential after hyperpolarization occured.
What’s NA+ -K+-ATPase’s role in maintaining resting membrane potential?
NA+-K+-ATPase maintains the resting potential by maintaining the amount of potassium ions needed inside the cell and sodium ions outside of the cell to keep it in the balance needed for resting membrane potential
What is an example of depolarization?
An example of depolarization would be when a vesicle of the cell lets in a hormone or neurotransmitter that opens up a sodium NA+) channel
What is an example of Repolarization?
An example of repolarization would be after change in charge the Sodium potassium pump brings it back to resting potential
What is an example of hyperpolarization?
An example of hyperpolarization would if a vesicle of a cell lets in a neurotransmitter or a hormone that opens up a chloride channel making it more negative
What is the charge of a membrane’s resting potential?
-70 mV
What causes for the resting potential of a membrane to occur?
The membrane’s semipermiabilty keeping the positive and negative ions apart causing a difference in the ICF and ECF charges
