Lecture on Lipids and Membrane Transport

These flashcards cover key concepts related to the structure, function, and transport mechanisms of lipids and membranes as discussed in the lecture.

Lipid

A group of substances that are insoluble in water and primarily composed of fatty acids.

Membrane fluidity

The viscosity of the lipid bilayer of a cell membrane, affecting the movement of proteins and lipids within it.

Saturated fatty acids

Fatty acids with no double bonds between the carbon atoms, leading to straight chains.

Phospholipids

Lipids comprising a glycerol backbone, two fatty acids, and a phosphate group, essential for forming cell membranes.

Integral proteins

Proteins that are permanently attached to the cell membrane and span its entirety.

Peripheral proteins

Proteins that are attached to the exterior or interior surfaces of cellular membranes but do not penetrate the membrane.

Amphipathic

Molecules that contain both hydrophilic (water-attracting) and hydrophobic (water-repelling) parts.

Triacylglycerols

Fats that consist of three fatty acids linked to glycerol; primarily used for energy storage.

Transbilayer diffusion

The movement of lipids or proteins from one side of the membrane to the other, often occurring very slowly.

Facilitated diffusion

A process by which substances move across membranes with the help of transport proteins, without energy investment.

Active transport

The movement of substances across a membrane against their concentration gradient, requiring energy input.

Electrochemical gradient

The gradient generated by the combined effect of concentration and charge differences across a membrane.

Citric Acid Cycle (Krebs Cycle)

A series of chemical reactions used by all aerobic organisms to generate energy through the oxidation of acetyl-CoA.

Oxidative phosphorylation

The process by which ATP is produced as electrons are transferred through the electron transport chain and protons are pumped across the membrane.

Ubiquinone (Coenzyme Q)

A component of the electron transport chain that transports electrons and protons.

Electron carriers

Molecules that transfer electrons from one molecule to another in biological systems, crucial in metabolic pathways.

Nicotinamide adenine dinucleotide (NAD)

An important coenzyme in biological oxidation-reduction reactions.

Glycolysis

A series of reactions that convert glucose into pyruvate, producing ATP and NADH.

Acetyl-CoA

A central metabolite that plays a vital role in many metabolic pathways, particularly in the citric acid cycle.