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It is dicult to manufacture anything on the nanometer scale (i.e. < 100 nm). As an example, we cannot use photolithography to manufacture computer chips, as visible light has a spectrum of 300- 700 nanometers. Structures under half of the wavelength used in such processes can only be made by using special tricks. Industry now turns to UV light to achieve a nanometer scale lithography (now 22nm for Intel Haswell). The nature solves the problem by using molecular self-assembly of molecular and macromolecular building blocks.
Characteristics of life
- Response to stimuli
- Compartmentalizied (cells)
- Maintains homeostasis
- Biological membranes are thin (3-5 mm), lipid bilayers. They are electrical insulating and provide a barrier to flux of ions. In cells, energy is stored by concentration gradients. Lipids and fats (triglycerides) store a lot of energy since they contain a lot of carbon in a reduced form.
- Inspired by biological membranes, lipid vesicles are sometimes used for drug delivery.
What is an orbital?
An atomic orbital describes the probability distribution of the location of electrons.
What is a Van der Wall bond?
- Van der Waals interactions are attractive forces due to transient dipoles that induce transient dipoles in neighboring atoms or molecules. These attractive forces have very short range.
- Van der Waals forces are induced by transient dipoles within atoms or molecules themselves, or due to other molecules. They are generally non-directional.
What is a hydrogen bond?
A hydrogen bond is the electromagnetic attractive interaction between polar molecules, in which hydrogen (H) is bound to a highly electronegative atom, such as nitrogen (N), oxygen (O) or fluorine (F).