Biology 1002B Lecture Notes - Lecture 5: Active Transport, Photoreceptor Cell, Endergonic Reaction
Document Summary
It has a hydrophilic head and hydrophobic tail. Phospholipid bilayer can be formed spontaneous, no energy required. The membrane are more than 50% protein. Saturated vs. unsaturated: unsaturated have lots of kinks in them, lots of movement. Physiological importance of unsaturation: saturated ->(desaturase) -> unsaturated, when you regulate desaturase, you can regulate unsaturation, maintaining proper fluidity is very important, can"t be too lucid and can"t be too rigid. We use proteins to transport others across the membrane, the membrane protein. Membrane proteins: the protein interact with the membrane, they can form some kind of channels, for membrane protein, all one need is the primary sequence. Some sequences are rich in polar amino acids sequences and some sequences are non-polar amino acid, it takes about 17 to 20 amino acids made of predominantly of non-polar amino acid, then you"ll know it"s a membrane protein. Membrane transport: diffusion: if the molecules are small and non-charged.