8 Take ¼ sheet of paperDraw 4 consecutive amino acids across the top evenly spaced.Cut the paper so you have a strip with the 4 amino acids.Curl the paper around so you have a helix – connect amino acids with peptide bonds - draw in peptide bonds.If you do not wish to keep your protein - denature your protein and place in the recycling bin
9 Proteins Peptide – 2 or more amino acids bonded together Polypeptide – 10 or more amino acidsProtein – 50 or more amino acids bonded togetherAre long chains of amino acids that start to fold into 3-d shapes.Cooking causes DENATURATION – unfolding of the protein molecule
10 Functions of proteins Enzymes – are catalysts for cellular reactions. Transport proteins – hemoglobin is an example of this – it carries oxygen to all parts of your body.Structural proteins – collagen is an example of this – it make up skin, tendons, hair, and fingernailsHormones – Insulin is a protein that carries signals from one part of the body to another.
11 Enzymes A biological catalyst Substrate – bind to specific sites on enzyme molecules – Like a lock= where the key fits; and a key= enzyme.Active site – is the lock to which the enzyme binds, or the key fits.
12 CarbohydratesCarbohydrates are made of carbon, hydrogen, and oxygen atoms, always in a ratio of 1:2:1; functional groups of alcohols –OH, and -C=O are common.Carbohydrates are the key source of energy used by living things.The building blocks of carbohydrates are sugars, such as glucose and fructose.
13 How do two monosaccharides combine to make a polysaccharide? are called ‘simpleSugars’.Two monomers linked together are calledDisaccharides
15 Functions of carbohydrates Glucose – a monosaccharide that is found in our blood : commonly referred to as “blood sugar”Sucrose –a disaccharide commonly called table sugar. This is too big to be taken into the bloodstream and is broken down in the small intestine.Polysaccharides – many monomers 12 or more monomer units strung together – pasta is an example of this. Starch, Glycogen and Cellulose are examples of polysaccharides.
17 Lipids Lipids ARE NOT Always POLYMERS. Lipids are large, are nonpolar, are hydrophobic (water/fear – they are insoluble in water)Lipids ARE NOT Always POLYMERS.Lipids are made up of Fatty acids – long-chained carboxylic acids.Fats are eithersaturated – have the maximum number of hydrogensUnsaturated – have double bonds, so they could add more hydrogens.
18 Types of lipids Fatty acids Triglycerides – used in making soap, cell membranes (called phospholipids)Waxes – contain fatty acidsSteroids – have no fatty acid chains, have cyclic rings - are used as hormones which regulate metabolic processes.
19 Functions of lipids Store energy efficiently Make up most of the structure of the cell membrane
21 What are they ? The 4th type of macromolecules The chemical link between generationsThe source of genetic information in chromosomes
22 What do they do ? Dictate amino-acid sequence in proteins Give information to chromosomes, which is then passed from parent to offspring
23 What are they made of ?Simple units (monomers) called nucleotides, connected in long chainsNucleotides have 3 parts:1- A phosphate group ( P )2- 5-Carbon sugar (pentose)3- Nitrogen containing base(made of C, H and N)The P groups make the links that unite the sugars (hence a “sugar- phosphate backbone”
24 Two types of Nucleotides (depending on the sugar they contain) 1- Ribonucleic acids (RNA)The pentose sugar is Ribose (has a hydroxyl group in the 3rd carbon---OH)2- Deoxyribonucleic acids (DNA)The pentose sugar is Deoxyribose (has just an hydrogen in the same place--- H) Deoxy = “minus oxygen”
25 DNA Nucleotides Composition (3 parts): 1- Deoxyribose sugar (no O in 3rd carbon)2- Phosphate group3- One of 4 types of bases (all containing nitrogen):- Adenine- Thymine (Only in DNA)- Cytosine- Guanine
26 RNA Nucleotides Composition ( 3 parts): 1- Ribose sugar (with O in 3rd carbon)2- Phosphate group3- One of 4 types of bases (all containing nitrogen):- Adenine- Uracyl (only in RNA)- Cytosine- Guanine
27 DNA vs RNA DNA 1- Deoxyribose sugar 2- Bases: Adenine, Thymine, Cytosine, Guanine3- Double-stranded helix arrangementRNA1- Ribose sugar2- Bases: Adenine, Uracyl, Cytosine, Guanine4- Single stranded
28 The Double Helix (DNA) Structural model: Model proposed by Watson & Crick, 1953Two sugar-phosphate strands, next to each other, but running in opposite directions.Specific Hydrogen bonds occur among bases from one chain to the other:A---T , C---GDue to this specificity, a certain base on one strand indicates a certain base in the other.The 2 strands intertwine, forming a double- helix that winds around a central axis
30 Quick Check An ending of –yne means? An ending of –ene means? An ending of –ane means?
31 Metabolism vs anabolism METABOLISM: Changing complex molecules (nucleic acids, polysaccarides, proteins, triglycerides) into their building blocks (amino acids, fatty acids, nucleotides, monosaccharides)ANABOLISM: The reverse: linking the building blocks (amino acids, fatty acids, nucleotides, monosaccharides) to make a complex molecule (nucleic acids, polysaccarides, proteins, triglycerides)