The 4 types of bonds important in Biology
Essential for life to exist
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Ionic Bonds
Bonds formed between ions with opposite charges
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Covalent Bonds
Atoms bonded by sharing electrons
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Hydrogen Bonds
Hydrogen attracts and bonds to neighboring partial negative charges
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van der Waals interactions
Intermolecular interactions that do not involve covalent bonds or ions, but rather attractions between neutral chemical species due to fluctuating electron distributions
Biology is Dynamic
Holding the molecules of life together—for a time
We need many different kinds of bonds— weak and strong—to play various roles in biochemical interactions, including structural, signaling, and energy storage and transfer.
Intramolecular and intermolecular forces are both involved. These bonds vary in their strengths, which is needed for them to serve different purposes. We don't want all bonds to be permanent.
Intramolecular and intermolecular forces are both involved. These bonds vary in their strengths, which is needed for them to serve different purposes. We don't want all bonds to be permanent.
When studied in chemistry, we think of Ionic bonds and Covalent bonds as having an overlapping range of strengths. But remember, in biochemistry, almost everything is happening in the context of water (in aqueous solution). This means Ionic bonds tend to dissociate in water. Thus, we will think of these bonds in the following order (strongest to weakest):
Covalent > Ionic > Hydrogen > van der Waals
Also note that in the field of chemistry, the weakest intermolecular bonds are more commonly referred to as “dispersion forces.”
Also note that in the field of chemistry, the weakest intermolecular bonds are more commonly referred to as “dispersion forces.”
Recommended reading
The definitive text
Campbell's Biology is the standard text used in most first-year college biology courses. Reliably researched and well-written, with clear illustrations.
Related Topic
Hydrogen Bonding in Water
The unusual properties of water that support life can mostly be explained by the extensive hydrogen bonds holding the molecules together
