Biological Molecules Unit 1 Flashcards
In a Eukaryotic Cell where would you find DNA & RNA? (6)
Nucleus, Cytosol, Mitochondrion, Chloroplast, Lysosome, Plant vacuole
What linked patterns make up large molecules?
Polymers, and Monomers
What causes polymers to form and break up?
Polymers form via dehydration reactions (loss of water molecule), and are broken up by hydrolysis reactions (gain water molecule)
What is the general formula for carbohydrates?
(CH2O)n
What is a monosaccharide, and how many carbon atoms does it have?
The most basic form of carbohydrate, and between 3-7 carbon atoms
What is a disaccharide and what links it together?
A disaccharide is two monosaccharides attached with a glycosidic linkage
How are glycosidic linkages formed?
Dehydration reaction
What is a glycosidic linkage?
A type of covalent bond that joins carbohydrate molecules to another group
What polysaccharides make up starch and what organisms utilise starch as their main storage?
Amylose and amylopectin (polymers of glucose), and plants and some algae
What is the main storage polysaccharide for animals, and what is it similar to?
Glycogen, and similar to amylopectin (glucose polymer in plants/algae)
What are the enzymes that hydrolyse starch and glycogen in animals?
Amylases
What is the principal structural polysaccharide in plant cell walls?
Cellulose
In plants, what are the enzymes that hydrolyse cellulose called?
Cellulases
What are the five(5) main functions of carbohydrates?
Storage of energy & materials, transport of energy and materials, energy generation, building material (especially in cells walls of plants/protists, and cell surface activities including recognition and signalling
What are lipids, and what are they made of, and are they water soluble?
Lipids are fats, mainly consisting of hydrocarbons (C-C, C-H bonds), they aren’t water soluble
What two parts make up fatty acids?
A hydrophilic (water loving) carboxyl group, and an unbranched hydrophobic (water fearing) hydrocarbon chain
What makes fatty acids amphipathic?
It’s b/c they have both a hydrophobic, and hydrophilic region
What are four(4) structural variations in fatty acids?
Length of carbon chain, saturated (no C-C double bonds) or unsaturated (1 or more C-C double bonds), location of the double bonds, and cis & trans configuration at double bonds and its almost alway cis (introduces bend)
What is a triacylglycerol?
They’re fatty acid esters of glycerol (3 carbon chain)
Triacylglycerol room temperature state in animals and plants?
Animals- solid at room temperature, make up most of common fat
Plants- liquid at room temperature (oil)
What are phospholipids, and describe their structure.
A type of lipid that spontaneously forms a bilayer once placed in a aqueous solution, and has a hydrophilic head, and two hydrophobic tails
What are steroid and what is their function?
Steroid are lipids and produce hormones (estrogen & testosterone)
What are the six(6) main functions of lipids?
Membrane structure, energy storage, energy generation, thermal insulation, signalling and buoyancy
What are proteins?
Polymers composed of many amino acid monomers
What are amino acids?
Small molecules that are the building blocks of proteins. Chemically it is a carboxylic acid and an amine group attached to a alpha carbon. See amino acid picture.
How are amino acids attached together? And what do they form?
Amino acids are attached via a dehydration reaction, and form an unbranched polypeptide by forming peptide bonds w/ the amino acid residue
What is a polypeptide, and what do they create?
Polypeptide is a polymer composed of many amino acid residues, and they form proteins.
What are three(3) key features of a polypeptide?
A monotonous repeating N-C-C-N-C-C-N backbone, R groups extending from the backbone w/ differing orders from one polypeptide to another, and N-terminus (amino) and C-terminus (carboxyl) giving the polypeptide polarity.
What are the four(4) levels of polypeptide structure?
Primary, secondary, tertiary, and quaternary
How many tripeptides are possible?
20^3=8000, b/c there is 20 amino acid groups
What are the four(4) main groups of biological molecules?
Lipids (fats & oils), Proteins (amino acids), Carbohydrates (sugars), and nucleic acids (DNA/RNA)
What are the three(3) most common carbohydrates?
Glucose, fructose (plant sugar), and sucrose (glucose + fructose)
What are the four(4) major examples of polysaccharides in organisms?
Starch, glycogen, cellulose, chitin
What is the difference between alpha and beta glucose?
Positioning of 1 of the 4 hydroxyl groups. Alpha is when the -OH is below the carbon ring, and beta is when the -OH is above the carbon ring
What is the primary structure of polypeptides/proteins?
The one-dimensional sequence of amino acid residues
What is the secondary structure of polypeptides/proteins?
The three-dimensional shape resulting from the hydrogen bonding regions of the backbone that are close by in terms of the primary structure
What two(2) shapes do the secondary structure polypeptides/proteins have?
Alpha helix, and beta pleated sheet
What is the tertiary structure of the polypeptides/proteins?
The folded shape of the polypeptide arising from interactions among the R groups
What is the quaternary structure of the polypeptides/proteins?
Assembly of two or more polypeptide chains into a functional complex, due again to interactions among the R groups.
Do all functional proteins have quaternary structure?
No
What are the nine(9) functions of proteins?
Catalysis of biochemical reactions by enzymes, Cytoskeleton & motility, Structural proteins, signalling molecules (insulin), transcription factors, cell surface receptors (chemical stimuli), defence (antibodies), storage (starch amino acids), Transport (hemoglobin movement)
What are the two(2) types of nucleic acids, and describe them?
DNA-a double stranded helix held together mainly by complementary base pairing btwn strands
RNA-a single stranded, but can have some regions double helical structure resulting from intrastrand complementary base pairing
What are the five(5) main components of DNA & RNA?
Base (rings containing C & N), sugar (ribose in RNA & deoxyribose in DNA), phosphate group (negative charge), nucleoside (base+sugar), nucleotide (base+sugar+phosphate groups)
What are the four(4) main functions of nucleic acids?
Information storage (genes are made of DNA), information retrieval (gene expression), Energy currency (ATP,a ribonucleotide), and catalysis of some biochemical reaction by ribozymes)
What are three(3) examples of modified types of molecules?
Glycoproteins, proteoglycans, and glycolipids
Two(2) other molecules in cells that do not make up their own class?
Vitamins (small molecules), and secondary metabolites (molecules produced, but are not needed for basic universal processes
How are nucleotides linked together?
By phosphodiester bonds to give a polynucleotide strand
What is significant about the polynucleotide strand?
It has polarity, the 5’ & 3’ ends are different
Describe the DNA double helix?
Consists of two polynucleotide strands held together firmly by complementary base pairings that run antiparallel to each other.
What are the four(4) links named in DNA, and which pair together?
Adenine-Thymine, Cytosine-Guanine
What groups does the main structure of proteins consist of? (4)
Central C (alpha carbon), amino group (NH2), carboxyl group (COOH), and a hydrogen atom
What exactly happens when a protein becomes ‘denatured’?
Protein looses it’s higher order structure, but not its primary sequence. They’re usually non-functional
