If the material can fit through the pore, it stays in solution; if it is larger than the pore, it is trapped.
Particles in a ________ stay dispersed over time.
Colloid
A ___________ has even larger particles than a colloid, and these settle to the bottom of a container given time.
Suspension
True or False:
Blood is a suspension, a colloid and a solution.
True.
Red blood cells are suspended in plasma. Plasma is a colloid of large proteins dispersed in a solution of sodium chloride and other salts.
What is the name of the part of the kidney that filters subtances less than 10 kDa (10,000 Da) will pass through the biological filter system?
Glomerulus
The biological filter in the kidney passes all ___________, and also __________ and _______ __________ of smaller size.
monomers; sugar; protein polymers
What is the most abundant protein in the blood?
Albumin, is 68 kDa in size.
What is Active Transport?
Requires energy. Is used to move an ion against its concentration gradient.
Energy sources for active transport?
ATP
Pre-existing storage of energy in a concentration gradient.
When molecules are moved against their concentration gradient (from low concentration to high), energy is required.
Active Transport
Na+ is _______ outside, ________ inside.
high; low
K+ is _______ outside, _________ inside.
low; high
Na+/K+ pump moves both
against their concentration gradients (Na+ moves out, K+ moves in), splits ATP for energy to do this (ATPase).
Three Na+ ions rest in a pocket of the pump. Thes Na+ ions are expelled as _______ is split into ____ + _______, releasing the nergy needed to drive the pump. Then, two K+ ions _______ outside the cell and these are ________ inside the cell.
ATP; ADP; phosphate; bind; released
Since three positive charges are pumped out for every two allowed in, the cell is made more negative inside by the pump. We call this pump
electrogenic
Na+/K+ ATPase
(Na+/K+ pump)
Step 1:
Na+ gradient: high outside cell, low inside.
K+ gradient: low outside cell, high inside.
Pump wants to move both against their gradients.
ATP is used as energy source.
3 Na+ bind to pocket in pump protein
Na+/K+ ATPase
Step 2:
3 Na+ expelled from cell.
ATP split to ADP + P + energy
Na+/K+ ATPase
Step 3:
K+ pocket exposed
P released
Na+/K+ ATPase
Step4:
2 K+ enter cell.
Pump is reset to bind 3 more Na+
What is an Antiport System?
It is a form of Active transport.
When two ions move in opposite directions to drive the pump.
What is a Symport System?
It is a form of Active transport.
A molecule and an ion move in the same direction to drive the pump.
Cell surface proteins (receptors) can bind molecules the cell wants to take in. After the material binds to the receptor,
it is taken into the cell (endocytosis)
If the material is to be taken into the cell, it is called
Endocytosis.
If the material is expelled from the cell, it is called
Exocytosis.
All forms of endocytosis and exocytosis require energy from
ATP
Vescular Transport is
used to move large quantities of small things, or to move things too large to fit inside of a protein.
In receptor-mediated endocytosis, cell surface proteins
bind a substance of interest, and then signal the cell to begin the process of pinching off a vesicle.
Example of endocytosis would be
receptor-mediated endocytosis of low-density lipoprotein (LDL).
Low-density lipoprotein (LDL) particles are taken into the cell by this process so that the lipid may be used for cell metabolism.
LDL is one of the forms of
lipid in the bloodstream.
What is phagocytosis?
is the cell's way of eating things.
What is an important process for the defense of the body against invaders?
Phagocytosis
When invaders are detected, what surrounds and and kills them?
specialized white blood cells known as Macrophages and Neutrophils.
