knowt logo

The Chemistry of Life 

The Chemistry of Life 

Key points: 

- Three subatomic particles and their significance 

- The types of chemical bonds and how they form 

- The importance of hydrogen bonding to the properties of water 

- Four unique properties of water , and how each contributes to life on earth 

- How to interpret the pH scale 

- How changes in the pH can alter biological systems 

- The importance of buffers in the biological systems 

Matter consists of chemical elements in pure form and in combination called compounds.  

- MATTER: anything that takes up space and has mass 

- ELEMENT: a substance that cannot be broken down to other substances by chemical reactions 

- COMPOUND: a substance consisting of two or more elements combined in fixed ratio 

- Carbon, hydrogen, oxygen, nitrogen make up 96% of living matter. About 25% of the 92% natural elements are known to be essential to life 

- TRACE ELEMENTS: those required by organisms in only minute "trace" quantities 

An element's properties depend on the structure of its atoms 

- Atoms are the smallest unit of an element that still retains the property of the element. Atoms are made of neutrons, protons, and electrons 

- Protons are positively charged particles found in the nucleus of the atom 

- Electrons are negatively charged particles that are found in electron shells around the nucleus 

- Neutrons are particles with no charge that are found in the nucleus 

- ISOTOPES: forms of an element with differing numbers of neutrons 

-IONS: an atom or molecule with a net electrical charge due to the loss or gain of one or more electrons 

- ATOMIC NUMBER: the number or protons that an element possesses 

- MASS NUMBER: the sum of the protons and the neutrons 

The formation and function of molecules depend on chemical bonding between atoms 

- CHEMICAL BONDS: interactions between the valence electrons of different atoms. Atoms are held together by chemical bonds to form molecules  

The Chemistry of Life 

Key points: 

- Three subatomic particles and their significance 

- The types of chemical bonds and how they form 

- The importance of hydrogen bonding to the properties of water 

- Four unique properties of water , and how each contributes to life on earth 

- How to interpret the pH scale 

- How changes in the pH can alter biological systems 

- The importance of buffers in the biological systems 

Matter consists of chemical elements in pure form and in combination called compounds.  

- MATTER: anything that takes up space and has mass 

- ELEMENT: a substance that cannot be broken down to other substances by chemical reactions 

- COMPOUND: a substance consisting of two or more elements combined in fixed ratio 

- Carbon, hydrogen, oxygen, nitrogen make up 96% of living matter. About 25% of the 92% natural elements are known to be essential to life 

- TRACE ELEMENTS: those required by organisms in only minute "trace" quantities 

An element's properties depend on the structure of its atoms 

- Atoms are the smallest unit of an element that still retains the property of the element. Atoms are made of neutrons, protons, and electrons 

- Protons are positively charged particles found in the nucleus of the atom 

- Electrons are negatively charged particles that are found in electron shells around the nucleus 

- Neutrons are particles with no charge that are found in the nucleus 

- ISOTOPES: forms of an element with differing numbers of neutrons 

-IONS: an atom or molecule with a net electrical charge due to the loss or gain of one or more electrons 

- ATOMIC NUMBER: the number or protons that an element possesses 

- MASS NUMBER: the sum of the protons and the neutrons 

The formation and function of molecules depend on chemical bonding between atoms 

- CHEMICAL BONDS: interactions between the valence electrons of different atoms. Atoms are held together by chemical bonds to form molecules