* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Proteins Chapter 3 pages 54-58
Ancestral sequence reconstruction wikipedia , lookup
Expression vector wikipedia , lookup
Ribosomally synthesized and post-translationally modified peptides wikipedia , lookup
Fatty acid synthesis wikipedia , lookup
Deoxyribozyme wikipedia , lookup
Fatty acid metabolism wikipedia , lookup
Magnesium transporter wikipedia , lookup
Peptide synthesis wikipedia , lookup
Gene expression wikipedia , lookup
Interactome wikipedia , lookup
Artificial gene synthesis wikipedia , lookup
Nuclear magnetic resonance spectroscopy of proteins wikipedia , lookup
Metalloprotein wikipedia , lookup
Point mutation wikipedia , lookup
Western blot wikipedia , lookup
Protein–protein interaction wikipedia , lookup
Two-hybrid screening wikipedia , lookup
Genetic code wikipedia , lookup
Nucleic acid analogue wikipedia , lookup
Amino acid synthesis wikipedia , lookup
Proteolysis wikipedia , lookup
QUESTION 1 You are sitting by a lake, you drop a leaf on the lake and notice that it floats on the top of the water, which of the following properties of water could help explain what you observe? A) It is more dense when liquid than when frozen. B) It can dissolve large quantities of solutes. C) It has a high specific heat. D) It has a strong surface tension. E) None of these can explain what you observe. QUESTION 2 The formation of large, repetitive organic molecules from small monomers is a __________ reaction. A) dehydration synthesis B) reduction C) dehydrogenation D) hydrolysis QUESTION 3 Carbon is such an important molecule for life because: A)it can form chemical bonds with a maximum of four other atoms. B) it is part of the water molecule. C) it can hydrogen bond to so many molecules. D) it can be bonded ionically. E) it can form isomers. QUESTION 4 Glycogen is a polysaccharide used for energy storage by: A)monera B)fungi C)plants D)animals QUESTION 5 Which of the following solutions has the greatest concentration of hydrogen ions (H+)? A) gastric juice at pH 2 B) black coffee at pH 5 C) vinegar at pH 3 D) tomato juice at pH 4 E) household bleach at pH 12 Proteins and Nucleic Acids KEY WORDS: Protein Polypeptide Amino Acid Essential Amino Acid Denature 1°, 2°, 3°, 4° Structure Nucleic Acid Nucleotide DNA RNA Types of Proteins See Table 5.1 Structural Storage Enzymes Transport Hormones Antibodies Receptor Contractile Proteins Subunit = amino acid Amino acids have three parts: 1. Amino group 2. R group 3. Carboxyl group The 20 amino acids of proteins: nonpolar The 20 amino acids of proteins: polar and electrically charged Linking Amino Acids Dehydration synthesis: forms a covalent bond – A Peptide Bond Creates a polypeptide Making a polypeptide chain How are proteins able to do so many things? 20 different kinds amino acids - different R-groups Non-polar Polar Charged -O Scrabble Analogy Carbohydrates: Glucose G1 G1 G1 G1 G1 G1 Proteins: 20 amino acids • Glutamine E1 • Isoleucine I1 • Asparagine • Serine Hard to make more than one word • Threonine • Lysine • Arginine N1 S1 T1 K5 R1 Proteins Fold into Active Shape Protein function depends on shape Four Levels of Structure: Primary Secondary Tertiary Quaternary 1° 2° 3° 4° Primary (1°) Structure Sequence of amino acids in polypeptide The primary structure of a protein Secondary (2°) Structure Folds in part of amino acid chain: Hydrogen bonds b- pleated sheet a-helix Tertiary (3°) Structure 3D Packing of Polypeptides: More hydrogen bonds Examples of interactions contributing to the tertiary structure of a protein Quaternary (4°) Structure Interactions between 2+ polypeptides The quaternary structure of proteins Review: the four levels of protein structure Conformation of a protein, the enzyme lysozyme A chaperonin in action Denatured Proteins •Proteins can be unfolded = denatured •Can affect the behavior of the protein What can cause proteins to denature? Chemicals pH Heat Shape is critical for protein interactions EXAMPLE: Hemoglobin •4 Polypeptides •Binds Iron •Oxygen transport Protein Folding and Disease Many diseases caused by incorrect protein folding Mad Cow Disease Alzheimers Cystic Fibrosis Parkinson’s Disease Sickle Cell Anemia Arthritis Marfan Syndrome ALS (Lou Gehrig’s Disease) Cancer Diabetes Insipidus A single amino acid substitution in a protein causes sickle-cell disease Sickled cells Diet: Essential Amino Acids • 20 different amino acids • All living things have protein • 8 Essential Amino Acids can not be synthesized by our bodies - must be found in diet • All 8 essential amino acids are present in animal protein and soy beans Essential Amino Acids QUESTION Which of the following is contains all 8 essential amino acids? 1. Wheat 2. Soy beans 3. Brown rice 4. Corn 5. None of these Lipoproteins & Glycoproteins LIPOPROTEINS -Lipid + Protein -Used for transport of fats throughout the body -Example: HDL and LDL Cholesterol GLYCOPROTEINS -Carbohydrate + Protein -Receptors on the surface of cells QUESTION The myoglobin protein, which carries oxygen in muscle cells, only has the first three levels of protein structure (it lacks a quaternary level). From this you can conclude that myglobin: a)Is made of nucleic acids b)Is made of only one polypeptide chain c)Lacks hydrogen bonds d)Is not helical or pleated e)Is a fiber NUCLEIC ACIDS • Nucleic acids include RNA and DNA • Polymers made up of repeating monomers called nucleotides. James Watson and Francis Crick Rosalind Franklin X-ray crystallography NUCLEOTIDES 3 Main Components: • 5-Carbon Sugar (Pentose): RNA ribose, DNA deoxyribose • Phosphate Group • Nitrogen-containing base Nucleotides: Important Energy Storage Molecules • Adenosine Triphosphate (ATP): acts like cell’s battery, providing energy for most activities. RNA and DNA SIMILARITIES: • 5-carbon sugar • Phosphate group DIFFERENCES: • Nucleotides – DNA: Adenine, Guanine, Cytosine, Thymine – RNA: Adenine, Guanine, Cytosine, Uracil • Sugar – DNA: Deoxyribose – RNA: Ribose Nucleic Acid Synthesis • Nucleotides joined by dehydration synthesis • Covalent bond forms between PHOSPHATE GROUP and SUGAR Structure of DNA The components of nucleic acids The DNA double helix and its replication Polypeptide Sequence as Evidence for Evolutionary Relationships Nucleotides are to ____ as ____ are to proteins. • Nucleic acids; amino acids • Amino acids; polypeptides • Glycosidic linkages; polypeptide linkages • Genes; enzymes • Polymers; polypeptides The structural level of a protein least affected by a disruption in hydrogen bonding is • Primary • Secondary • Tertiary • Quaternary • All equally affected Which of the following is not a protein? • Hemoglobin • cholesterol • An antibody • An enzyme • Insulin