Topic 1.3-1.6: Biological Molecules

What is a monomer?

a small, individual molecule that serves as a building block

What is a polymer?

a large macromolecule formed by many repeating monomers chemically bonded together

How does dehydration synthesis occur?

when two molecules join together by forming a covalent bond, resulting in the removal of a water molecule. A hydrogen atom and a hydroxyl group are removed from the reacting molecules.

How does hydrolysis occur?

when a molecule of water breaks a chemical bond in another compound, splitting the water molecule into a hydrogen ion (H+) and a hydroxyl group (-OH)

What elements are found in Carbs?

Carbon, Hydrogen, Oxygen

What elements are found in lipids?

Carbon, Hydrogen, Oxygen (sometimes phosphorous, nitrogen or sulfur)

Describe the chemical structure of monosaccharides + disaccharides

single-unit sugars with the general formula, forming either open chains or ring structures.

when two monosaccharides are linked by a glycosidic bond

Describe the chemical structure of polysaccharides

complex carbs formed from hundreds to thousands of monosaccharide units linked together by glycosidic bonds.

Differ between starch, glycogen, cellulose, and chitin.

Starch is plant energy storage, while glycogen is animal energy storage. Cellulose is a structural component of plant cells, and chitin is the structural component for fungal cell walls and arthropod exoskeletons (animal cells)

Describe the chemical structure of a basic fat

a glycerol backbone (3 carbon alcohol) and three fatty acid chains ( long hydrocarbon chains) attached via ester bonds.

Describe the chemical structure of a phospholipid.

a hydrophilic (water-loving) phosphate-containing head and two hydrophobic (water-fearing) fatty acid tails, all attached to a glycerol backbone.

Describe the chemical structure of a steroid and cholesterol.

Steroid is a lipid with a distinct chemical structure of 4 fused hydrocarbon rings

Cholesterol is a type of steroid that has a 4 ring nucleus, hydrocarbon tail, and a hydroxyl group on the A ring .

Why are all lipids grouped together despite not forming polymers?

They are all hydrophobic (defined by this characteristic behavior in water)

What is the monomer of proteins? Describe the basic structure of this monomer.

Amino acid; features a central carbon atom bonded to an amino group, a carboxyl group, a hydrogen atom, and a unique R-group that gives each amino acid its specific chemical properties.

Amino acids can be considered hydrophilic or  hydrophobic. Why? How does this influence protein folding?

based on the chemical propertien of their unique side chains, or R-groups. This characteristic is a driving force behind protein folding, guiding the polypeptide chain its specific, functional three-dimensional shape

Describe the 4 levels of protein structure.

Primary: sequence of amino acids; Secondary: local folding into alpha-helices or beta-pleated sheets; Tertiary: overall 3D shape of a single polypeptide chain; Quaternary: arrangement of multiple polypeptide subunits

What type(s) of bonding occur in each protein level? Where/How do these bonds occur?

Primary: covalent; Secondary: hydrogen bonds b/t backbone atoms; Tertiary: various noncovalent interactions; Quaternary: same as tertiary

What is the monomer of nucleic acids? Describe the basic structure of this monomer.

nucleotide; phosphate group, five-carbon sugar, and a nitrogenous base

What kinds of nitrogenous bases are there?

purines (adenine and guanine) and pyrimidines (cytosine, thymine, and uracil)

How are the nitrogenous bases similar? different?

All organic molecules containing carbon and nitrogen atoms and form the basis of genetic material. Differ b/c their structure, with two types defined by one or two rings, and the specific type of base found in DNA or RNA