Unit Seven: Cell Structure And Function, Cell Transport, And Cell Communication Flashcards
How large are cells?
1 um to 5 cm
What basic structures are present on all cells?
Plasma membrane
Nuclear region
Cytoplasm
Ribosomes
Why are cells surface to volume ratio important?
The bigger the ratio the harder it is to divide and small cells function more effectively
What are the domains of prokaryotes?
Archaea
Bacteria
What is included on the eukaryotic domain?
Protista
Fungi
Plants
Animals
Theory of endosymbiosis
Organelles were once free living bacteria that were incorporated into a larger eukaryotic cell
What is the role of the plasma membrane?
Regulate movement of materials into and out of the cell and protect it from the outside environment
Phospholipids
Made of glycerol, phosphate (polar), and 2 fatty acid tails (non-polar) and a phospholipid via layer forms around the cell membrane
Integral proteins
Channel, carrier, cell recognition, receptor, and enzymatic proteins
Channel proteins
Allows molecules to pass through
Carrier proteins
Combine with a substance and help it pass through
Cell recognition proteins
Identify cell to surrounding cells
Receptor proteins
Bind to a molecule causing a change in cell activity
Enzymatic proteins
Catalyze cellular reactions
Fluid mosaic model
Singer and Nicholson suggested this to describe the ingredients and consistency of the plasma membrane. It is fluid because the individual components are loosely held together and there is latteral movement of the parts and mosaic because of th various components
Glycolipid and glycoproteins
Carbohydrate chains attached to protein or phospholipids to function adhesion, reception, and cell recognition
What can pass through the plasma membrane?
Water, small, non-charged molecules can pass freely
Large molecules need to be transported by vesicle formation
Passive transport
Not everything can pass through
Diffusion
Movement of molecules from high to low concentration until solute and solvent are evenly distributed
Facilitated diffusion
Uses carrier proteins to move from high to low concentration until solute and solvent are eual
Osmosis
The movement of water molecules down a concentration across a semipermeable membrane from high to low concentration
Osmotic pressure
Pressure that develops in a system due to osmosis
Water potential
Move from an area of higher water potential to lower water potential and is directly proportional to the pressure on a system
Water potential equation
W=Wp+Ws
Water potential equals pressure potential plus solute potential
Wp
Usually 0
Ws
-iCRT (bars)
i
Ionization constant
C
Molar concentration