Structure of plasma membrane Flashcards
Identify parts of plasma membrane
- Phospholipid bilayer
- Types of proteins
- Carbohydrates
- Cholesterol
- Carbohydrate chain
- Protein Channel
Phospholipid
- A main molecule of which membranes are
composed - They have a phosphate
head and two fatty acid tails
Phospholipid bilayer
- A double
a layer of amphiphilic molecules - Forms the primary component of membranes
Phosphate head
The hydrophilic
subunit of a phospholipid
Fatty acid tail
The hydrophobic
lipid subunit of a phospholipid
Polar:
- Molecule with
both a positive end and negative end. - These tend to be hydrophilic
Polar Substances:
- Attracted to
- Dissolve in
Nonpolar:
- Molecule without a clearly positive or negative end.
- These tend to
be hydrophobic
Amphipathic: the phospholipid bilayer is?
Molecules with both:
- Hydrophilic and hydrophobic components
Phospholipid bilayer:
- an ex. of this
- Stable
Amphipathic is also known as:
Amphiphilic
Phospholipid Bilayer - Polar VS non-polar
Polar:
Phosphate head
The phosphate head is:
* made of a glycerol and phosphate group
* negatively charged, making it hydrophilic (‘water-loving’) and polar.
Two Fatty acid tails
The two fatty acid tails are:
* made of long chains of carbon and hydrogen
* uncharged, hydrophobic (‘water-fearing’), and nonpolar.
Hydrophilic
- (‘water-loving’)
- Attracted to water
Hydrophobic
- (‘water-fearing’)
- Repels water
Amphipathic makes the plasma membrane:
More stable due to polar and non-polar parts of the membrane
Nonpolar molecules are:
attracted to and dissolve in
nonpolar substances
Non-polar substances:
- Attracted to
- Dissolve in
Non-polar molecules do not:
Interact with polar molecules
The phosphate head is:
The phosphate head is:
* made of a glycerol and phosphate group
* negatively charged, making it hydrophilic (‘water-loving’) and polar.
The two fatty acid tails are:
The two fatty acid tails are:
* made of long chains of carbon and hydrogen
* uncharged, hydrophobic (‘water-fearing’), and nonpolar.
Water is a polar or non-polar substance?
- Polar
Why the phospholipid bilayer comment on its structural features relative position and why?
Phosphate head:
(to reinforce the notion) because of its hydrophilic nature; it is attracted to water
Two fatty acid tails:
- form the middle portion of the bilayer because it is hydrophobic; not attracted to water
Phosphate head/ two fatty acid tails which one is oriented towards, the aqueous intra- and
extracellular environments.
Phosphate head
Different types of proteins:
- Integral protein – proteins that
are a permanent part of the
membrane - Transmembrane protein – integral
proteins that span the entire bilayer - Peripheral protein – are
temporarily attached to the
plasma membrane
Carbohydrates: what they are and where in relation to the structure of the plasma membrane
What they are:
- Biomacromolecule made from
monosaccharide monomers
consisting of carbon, hydrogen,
and oxygen. Also known as
saccharides or sugars
Where:
- Usually in chains that extend
outside the cell
- Rooted in the
membrane to lipids (glycolipids)
or proteins (glycoproteins)
Cholesterol: in what cells
- A lipid steroid that embeds itself
between the fatty acid tails of
the phospholipid bilayer in animal
cells
Protein:
Biomacromolecule made of amino
acid monomers folded into a 3D shape
Consisting of:
- Carbon,
- Hydrogen
- Oxygen
- Nitrogen
- Sometimes sulphur
Consisting of: carbohydrates
