Chapter 3 (Exam One) Flashcards
What are trans-fats? (5)
(a type of fat, or lipid)
- Are made by adding hydrogen to unsaturated fats, a process called hydrogenation.
- Are used to increase food shelf life and flavor/texture.
- May cause worse health effects than saturated fat in an individual’s diet.
- FDA now requires trans-fat labeling on foods and in foods in restaurants.
What are organic molecules? What’s another name for them?
molecules that contain both carbon and hydrogen atoms; biomolecules
What four classes of organic molecules exist in living organisms?
Carbohydrates
Lipids
Proteins
Nucleic Acids
Describe the carbon atom. How many covalent bonds can it form?
The carbon atom is small with only 6 electrons,
two in the first shell and four in the outer shell.
Carbon can form four covalent bonds.
Describe the carbon atom’s covalent bonds
- Bonds with carbon, nitrogen, hydrogen, oxygen,
phosphorus and sulfur. - The C-C bond is very stable.
- Long carbon chains, hydrocarbons, can be formed.
- Besides single bonds, double bonds, triple bonds and
ring structures (cylic) are also possible. (carbon, nitrogen) - Branches at any carbon make carbon chains more
complex.
The carbon chain of an organic molecule is called
its skeleton or backbone
What are functional groups? What do they do? Examples (6)
clusters of specific atoms bonded to the carbon skeleton with characteristic structures and functions.
What are isomers? Examples
organic molecules that have identical molecular formulas but different arrangements of atoms. Isomers have different chemical properties and react differently with other molecules.
glyceraldehyde and dihydroxyacetone
What do biomolecules usually consist of?
repeating units
What are the repeating units in a biomolecule called?
Each repeating unit is called a monomer.
What is a polymer? Name an example
A molecule composed of monomers is called a polymer (many parts).
Example: amino acids (monomer) are
joined together to form a protein
(polymer)
What biomolecule is not a polymer and why?
Lipids are not polymers because they contain two different types of subunits.
What are the subunits (monomers) and polymer of carbohydrates?
monomers: Monosaccharide
polymer: Polysaccharide
What are the subunits (monomers) and polymer of lipids?
monomers: Glycerol and fatty acids
polymer: fat
What are the subunits (monomers) and polymer of proteins?
monomers: amino acids
polymer: polypeptide
What is organic chemistry?
It deals with carbon and hydrogen
inorganic organic
Inorganic: is what you find it in
Organic: groups
What are the subunits (monomers) and polymer of nucleic acids?
monomers: nucleotide
polymer: DNA, RNA
What is a dehydration reaction? What does it do?
a chemical reaction in which subunits are joined together by the formation of a covalent bond and water is produced during the reaction.
Used to connect monomers together to make
polymers
a hydroxyl (— OH) group is removed from one monomer and a hydrogen (— H) is removed from the other.
What is hydrolysis? What does it do?
'"water breaking" A hydrolysis reaction is a chemical reaction in which a water molecule is added to break a covalent bond. Used to break down polymers into monomers A hydroxyl (— OH) group from water attaches to one monomer and hydrogen (— H) attaches to the other.
These special molecules are required for cells to carry out dehydration synthesis and hydrolysis reactions.
enzymes
What are enzymes? What are their characteristics?
a molecule that speeds up a chemical reaction.
Enzymes are not consumed in the reaction.
Enzymes are not changed by the reaction.
Enzymes are catalysts.
What are the functions of carbohydrates?
Energy source
Provide building material (structural role)
What do carbohydrates contain?
carbon, hydrogen and oxygen atoms in a 1:2:1 ratio
What are the varieties of carbohydrates? (3)
monosaccharides, disaccharides, and polysaccharides
What is a monosaccharide? Describe it
a single sugar molecule.
It is also called a simple sugar.
It has a backbone of 3 to 7 carbon atoms.
What are some examples of monosaccharides? (2)
- Glucose (blood sugar), fructose (fruit sugar), and galactose: Hexoses – six carbon atoms
- Ribose and deoxyribose (sugars contained in
nucleotides, the monomer of DNA): Pentoses – five carbon atoms
What are disaccharides?
A disaccharide contains two monosaccharides joined together by dehydration synthesis.
Name examples of disaccharides and what they are contained of. (4)
- Lactose (milk sugar) is composed of galactose and
glucose. - Sucrose (table sugar) is composed of glucose and
fructose. - Maltose is composed of two glucose molecules.
- Lactose-intolerant individuals lack the enzyme
lactose which breaks down lactose into galactose
and glucose.
What is a polysaccharide?
A polysaccharide is a polymer of monosaccharides.
Name examples of polysaccharides and what they do. (5)
- Starch provides energy storage in plants.
- Glycogen provides energy storage in animals.
- Cellulose is found in the cell walls of plants.
- Most abundant organic molecule on earth.
- Animals are unable to digest cellulose. - Chitin is found in the cell walls of fungi and exoskeleton of some animals.
- Peptidoglycan is found in the cell walls of bacteria.
- its monomers contain an amino acid chain
Describe lipids and name their functions (5)
Varied in structure Large, nonpolar molecules that are insoluble in water Functions: 1. Long-term energy storage 2. Structural components 3. Heat retention 4. Cell communication and regulation 5. Protection
What are the varieties of lipids?
fats, oils, phospholipids, steroids, waxes