Lesson 1.7 Flashcards
According to this model, membrane consist of lipid by layer and globular Proteins which are in bedded within the lipid bilayer
Fluid mosaic Model by S. Singer and G. nicolson
Has a hydrophobic and hydrophilic regions
Lipid bilayer
Proteins also known as
Glycoproteins
Lipids also known as
Glycolipids
The movement of substances through membranes without using energy
Passive transport
Three kinds of passive transport
Simple diffusion
Osmosis
Facilitated Diffusion
Is the movement of substances from a region of higher concentration to a region of lower concentration
Simple diffusion
Is a difference in concentration of a certain substance in one hour and the concentration in another Adjacent area
Concentration gradient
Factors that affect diffusion across the semi permeable membrane
Size
Charge of particles
Small non-polar molecules That can go in and out freely
H2O, 02, CO2, fatty acid‘s
Large molecules like, cannot go in and out freely
Proteins and carbohydrates
Ios such as, cannot pass through readily because of the presence of hydrophobic region
OH, K+, Ca+++
The diffusion of water across a selectively Premable membrane
Osmosis
Moves down it’s concentration gradient
Water
Three teams that are used to indicate the differences between two solutions
Isotonic, hypertonic and hypotonic
Comes from the Latin root meaning Strength
Suffix tonic
Refers to the concentration of solutes in the solutions
Tonicity and strength
The concentration of solutes Surrounding this so equals the concentration of solute inside the cell
Isotonic solution
The concentration of solute surrounding the cell is higher than that inside the cell
Hypertonic solution
If the cells loses too much water, the cell will shrink
Plasmolysis (or crenation in the case of animal cell)
The concentration of solutes surrounding this song is lower that that inside the cell
Hypotonic solution
place in solution of different sugar concentration
Red blood cells or RBC
- Rbc an external solution or the same concentration
- water entering the RBC = water leaving
- what happens? No changes in RBC sizes
Isotonic
- rbc are place in a very concentrated sugar solution
- RBC are filute compred to external solution and lose water
- waht happens? RBC Shrink
HYPERTONIC
- RBC are place in dilute sugar solution
- RBC take up water
- What happens? RBC swell and finally burst
Hypotonic
It is a form of passive transport that requires transport proteins in the membrane
Facilitated diffusion
Is an example of large polar molecule that is transported through the membrane by facilitated diffusion
Glucose
Bind to specific salute to be transported and cause changes in the shape of protein
Carrier proteins
Not bind the solute
Channel proteins
Is the movement of substances from the region of lower concentration to a region of greater concentration in the choirs expenditure cellular energy
Active transport
It is one of the well studied examples of active transport
Sodium potassium pump
Two types of movement across cell membrane
Endocytosis
Exocytosis
The cell engulfs particles into a pouch formed bu the in folding of the cell membrane
Endocytosis
Three types of endocytosis
Phagocytosis
Pinocytosis
Cell eating, the cell engulfs solid particles into much larger vesicles, sometimes called VACUOLES
Phagocytosis
In human, two types of white blood cells specialized in phagocytosis
Neutrophils
Manocytes
cell drinking, it is similar to phagocytosis except that the cell engulfs droplets of fluid instead of solid particles, also forming latge vacuoles within it.
Pinocytosis
It is the reverse of endocytosis
Exocytosis
