100 likes | 426 Views
Carbon and Carbon-Based Molecules. Mr. Chapman Biology 30. Your body’s structures contain a great deal of carbon – A diamond is composed entirely of carbon!. Carbon: The Building Block of Life.
E N D
Carbon and Carbon-Based Molecules Mr. Chapman Biology 30 Your body’s structures contain a great deal of carbon – A diamond is composed entirely of carbon!
Carbon: The Building Block of Life • Carbon is often referred to as the building block of life. This is due to the fact that carbon atoms are the basis of most molecules that make up living things. • Over the next little while in class, we will learn about three types of carbon-based molecules that make up the vast majority of structures in all organisms: Carbohydrates, Lipids, and Proteins
Carbon has a Unique Atomic Structure • Think of a typical carbon atom. Carbon is interesting because it contains 4 electrons in its outer (or valence) shell. Do you think it is easier for carbon to lose electrons, or gain electrons? If it has 4 and it wants to have a full shell, is it easier to gain 4 or to lose 4?
Carbon SHARES Electrons • Since it is not particularly easy for carbon to gain electrons or lose electrons, it tends to share them. • Because it has 4 unpaired electrons in its outer orbit, carbon can make up to 4 covalent bonds with other atoms. • This allows carbon to bond to many different atoms, forming the backbone of many different molecules. • The molecules can be linear, circular, branched, or any variety of shapes. This leads to a great amount of molecular diversity.
Carbon-Based Molecules Have 3 Fundamental Structures: Notice that each carbon forms 4 bonds in total!
Carbon Makes Huge Molecules • Carbon chains can bond with other carbon chains or rings in any particular sequence to make gigantic molecules. • All of the large molecules are made up of smaller molecules that are bonded together. • This is similar to the way individual links make a bicycle chain.
Polymers In many carbon-based molecules, small subunits make up an entire structure. The subunits are called monomers. The entire molecules are called polymers.
Carbohydrates, Lipids & Proteins are 3 Important Carbon-Based Molecules The first type of molecule we will examine is carbohydrates.
Questions for Review • Why does carbon tend to share electrons rather than lose or gain them? • How many unpaired electrons does carbon have? How many bonds can it form, and what type are they? • Explain the difference between monomers and polymers.