All living cells are composed of 4 major groups of compounds. What are they?
- Carbhoydrates - form giant sugar molecules
- Fats - form larger structures
- Proteins - made from combinations of amino acids (20)
- Nucleic acid - formed from 4 kinds of nucleotide monomers (identical molecules)
What is a monosaccharide?
Monosaccharides: chain of 3 or more carbon atom, 1 of which forms a carbonyl group through a double bond with oxygen. E.g. glucose, ribose and fructose.
What are disaccharides?
Disaccharides consists of two monosaccharides linked together by glycosidic bonds (colvalent bonds). E.g. sucrose (table sugar) is made up of glucose and fructose through a condensation reaction.
What are oligosaccharides? Do they usually have functional groups or bound to other things?
- Made up of several (3-20) monosaccharides bound by glycosidic linkages (through condensation)
- Many have additional functional groups, which give them special properties
- Oligosaccharides are often covalently bonded to proteins and lipids on the outer cell surface, where they serve as recognition signals (e.g. different human blood groups (e.g ABO blood types) are oligiosaccharides
What are polysaccharides?
Polymers made up of hundreds or thousands of monosaccharides (e.g. starch, glycogen and cellulose)
What are some of the different types of lipids? And what are some of the different functions?
- fats and oils store energy
- phospholipids have structureal roles in cell membranes
- Steroids and modified fatty acidsd play regulatory roles as hormones and vitamins
Differenct functions:
- thermal insulation
- lipid coating around nerves provides electrical insulation
- oil or wax on surfaces of skin, fur and feathers repel water
Are monosaccharides, disaccharides, oligosaccharides and polysaccharides carbohydrates or a lipids?
They are carbhoydrates!
Are fats and oils triglycerides or glycerol?
- Fat and oils are triglycerids.
- Triglycerides are composed of two components: fatty acids (long nonpolar hydrocarbon chain and a polar carbxyl group) and glycerol (molecules with 3 hydroxyl groups)
- Triglyceride has 3 fatty acid molecules and one glycerol
- Made through 3 condensation reactions
- Carboxyl group of fatty acid bonds with hydroxyl group of glycerol, that make ester linkage (covalent bond) and release of a water molecule
What does it mean to be a saturated fatty acid?
Saturated fatty acids have no double bonds between carbons - it is saturated with H atoms. Thes fatty acid molecules are relativey rigid and straight, and they pack together tightly.
What does it mean to be an unsaturated fatty acid? What does monounsaturated and polyunsaturated mean?
- Unsaturated fatty acids: some double bonds in carbon chain
- Monounsaturated: one double bond
- Polyunsaturated: more than one
Unsaturated fatty acids pack together poorly and have a low melting point, and these triglycerides are usually liquids at room temperature.
Does fats or carbohydrates give more energy?
On a per weight basis, broken-down fats yield more than twice as much energy as degraded carbohydrates.
What gives phospholipids amphipathic properties?
- The phosphate group has a negative electric charge and is hyrophilic. The two fatty acids are hydrophobic, so avoid water and aggregate together or with other hydrophobic substances.
- They form a bilayer: water excluded from the core
What are some of the different forms and functions of proteins?
- Enzymes are catalytic proteins that speed up biochemical reactions
- Defensive proteins such as antibodies
- Hormonal & regulatory proteins (insulin’s control of physiological processes
- Receptor proteins, respond to molecular signals (insulin receptor)
- Storage proteins - chemical building blocks (amino acids)
- Structural proteins such as collagen provide physical stablity and movement
- Transport proteins such as hemoglobin carry substances within an organism
- Genetic regulatory proteins regulate when, how and what gene is expressed
- Energy storage and information storage ARE NOT USUALLY PERFORMED BY PROTEINS
Amino acids are the building blocks of proteins. What functional groups do amino acids have?
Amino acids have a carboxyl functional group and an amino functional group. Also attached are a hydrogen atom and a R functional group.
Amno acids exist in two isomeric forms. D- amino acids and L-amino acids. Where side is the amino group placed in each isomeric form and which form is more common?
D-amino acids: amino group right; dextro.
L-amino acids: amino group lfe; levo; most common
Peptide linkages form the backbone of a protein. What functional groups of amino acids react with each other to form this peptide linkage?
Carboxyl group of one amino acid reacts with amino group of another, undergoing a condensation reaction that forms a peptide linkage.
What are the 20 different amino acids that make up peptides.
6 amino acids are non-polar and alipathic.
3 amino acids are aromatic
4 amino acids are polar and uncharged
2 sulfur-containing amino acids
5 Acid and basic amino acids
What is the primary structure of a protein?
Primary structure of a protein is the sequence of amino acids. The equence determines secondary and tertiary structure - how the protein is folded.
What is the seconday structure of a protein?
Secondary structure can be:
alpha helix - right handed coil resulting from hydrogen bonding between N-H groups on one amino acid and C=O groups on another. R groups extend outwards
Beta pleated sheet: two or more polypeptide chains are alligned; hydrogen bonds from between the N-H on one chain and the C=O on the other.
What is the tertiary structure of a protein?
Bending and folding results in a macromolcules with sepcific three dimensional shape. The outer surfaces present function groups that can interact with other molecules/subunits.
In plain, Sinead English, the tertiary structure is like multiple secondary structures interacting together to form one subunit.
What are the different ways R-groups can interact to promote structure?
Disulfide bonds
Hydrogen bonds
Salt bridges
Hydrophobic interactions
What is the quaternary structure of a protein?
Quaternary structure results from interaction of subunits by hydrophobic interactions, van der Waals forces, ionic bonds and hydrogens. Each subunit has its own unique tertiary structure.
Not a flash card, just a fun fact. Apart from the primary structure, the type of amino acids can determine the three-dimensional strucutre of the protein and ultimatley its function.
Yay, gotta love fun facts.
Nucleic acids code and transmit biological information. There are two types. What are they?
DNA (deoxyribonucleic acid) and RNA (ribonucleic acid)
DNA is a macromolecules that encodes hereditary information and passes it from generation to generation.
RNA intermediate: information encoded in DNA is used to secify the amino acid sequence of proteins.
Information flows from DNA to DNA during reproduction.
In non-reproductive activites, information flows from DNA to RNA to proteins.
It is the proteins that ultimatley carry out life’s fuctions.
