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41 Cards in this Set
- Front
- Back
- 3rd side (hint)
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What two main purposes do monosaccharides serve in the cell?
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They serve as fuel for cells and raw material for building carbohydrates
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What is a disaccharide? What is the linkage called that joins adjacent monosaccharides?
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Forms when a dehydration reaction joins two monosaccharides into a single polymer. The linkage is called glycosidic linkage.
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What is produced as a byproduct when the type of bond in question 2 is formed?
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Water
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What is a polysaccharide? What two main functions do they serve in the cell?
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Polysaccharides are large polymers of sugars that have energy storage and structural roles.
The structure and function of a polysaccharide is determined by its sugar monomers and the positions of glycosidic linkages between the sugars |
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What types of organisms make starch? What is starch?
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Starch, a storage polysaccharide of plants, consists entirely of glucose monomers
Plants store surplus starch as granules within chloroplasts and other plastids. Glycogen is a storage polysaccharide made and used by animals |
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In what way is starch like a $10,000 bill?
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don't know
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What is cellulose and why is it so tough? What types of organisms make it and what do they use it for?
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The polysaccharide cellulose is a major component of the tough wall of plant cells
Like starch, cellulose is a polymer of glucose, but the glycosidic linkages differ The difference is based on two ring forms for glucose: alpha (a) and beta (b) Polymers with glucose are helical Polymers with glucose are straight In straight structures, H atoms on one strand can bond with OH groups on other strands Parallel cellulose molecules held together this way are grouped into microfibrils, which form strong building materials for plants |
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Is starch helical or straight? How about cellulose?
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Starch is helical. Cellulose is straight.
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Humans can’t digest cellulose but some herbivores (like cows) can. How do these animals manage to digest such a tough polysaccharide?
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These herbivores have symbiotic relationships with microbes that use enzymes to digest cellulose
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What is chitin? What types of organisms produce it and what do they use it for?
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Chitin, another structural poly-saccharide, is found in the exoskeleton of arthropods.
Chitin also provides structural support for the cell walls of many fungi. |
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In what way are lipids put together differently than the other three types of large biomolecules used by life?
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They don't form polymers.
The unifying feature of lipids is having little or no affinity for water. |
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Why are lipids hydrophobic?
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Lipids are hydrophobic because they consist mostly of hydrocarbons, which form nonpolar covalent bonds
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What is a fat? Is a lipid a type of fat or is a fat a type of lipid?
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Fats are constructed from two types of smaller molecules: glycerol and fatty acids
Glycerol is a three-carbon alcohol with a hydroxyl group attached to each carbon A fatty acid consists of a carboxyl group attached to a long carbon skeleton Fat is a type of lipid. |
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Know the difference between saturated and unsaturated fatty acids. Which are solid at room temperature? Be able to give one example of each.
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Saturated fatty acids have the maximum number of hydrogen atoms possible and no double bonds
Unsaturated fatty acids have one or more double bonds At room temp: Saturated = solid Unsaturated = liquid |
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What is the major function of fats?
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The major function of fats is energy storage. Fats can be stacked together tightly and fit nicely into a small space.
Humans and other mammals store their fat in adipose cells. Adipose tissue also cushions vital organs and insulates the body. |
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What is a phospholipid and what role do they play in cell membranes?
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In a phospholipid, two fatty acids and a phosphate group are attached to glycerol.
The two fatty acid tails are hydrophobic, but the phosphate group and its attachments form a hydrophilic head When phospholipids are added to water, they self-assemble into a bilayer, with the hydrophobic tails pointing toward the interior |
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What are steroids? Be able to give some examples. (I mentioned three types in class.)
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Steroids are lipids characterized by a carbon skeleton consisting of four fused rings.
Cholesterol, an important steroid, is a component in animal cell membranes Although cholesterol is essential in animals, high levels in the blood may contribute to cardiovascular disease. |
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What happens to wildlife when estrogen-like pollutants are dumped into the environment?
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don't know
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Be able to list several different functions that proteins play in the cell.
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Movement
Enzymes Defense against foregin substances Structure support Cellular communication Transport Storage |
MEDS CT'S
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What are enzymes? Are all proteins enzymes? Are all enzymes proteins?
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Enzymes are (usually) a type of protein that acts as a catalyst to speed up chemical reactions
Enzymes can perform their functions repeatedly, functioning as workhorses that carry out the processes of life |
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21. What is the difference between a polypeptide and a protein?
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Polypeptides are polymers built from the same set of 20 amino acids
A protein consists of one or more folded and functional polypeptides |
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22. Be able to draw out a short polypeptide chain, showing the location of all the atoms, including the location of the “R” group. (You do not need to memorize the chemical structures of the R groups.)
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picture
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23. What are the four major categories of R groups (amino acid side chains) found in proteins?
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Nonpolar, polar, acidic electrically charged, basic electrically charged
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24. How many amino acids does life use to form proteins?
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20
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25. What byproduct is produced when a peptide bond is formed? Be able to draw out this type of reaction.
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Water (Lect 5, slide 56)
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26. What ultimately determines how a protein will fold and how it will function in the cell?
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The sequence of amino acids determines a protein’s three-dimensional structure
A protein’s three-dimensional structure determines its function |
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27. Know the four levels of structure found in proteins. Do all proteins have all four structural levels? Explain.
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The primary structure of a protein is its unique sequence of amino acids (coded by DNA)
Secondary structure, found in most proteins, consists of coils and folds in the polypeptide chain backbone Tertiary structure is determined by interactions among various side chains (R groups) Quaternary structure results when a protein consists of multiple folded polypeptide chains |
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28. What types of bonds hold together the secondary structure of a protein?
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The coils and folds of secondary structure result from hydrogen bonds between repeating constituents of the polypeptide backbone
Typical secondary structures are a coil called an (alpha) helix and a folded structure called a (beta) pleated sheet |
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29. What types of bonds hold together the tertiary and quarternary structures of a protein?
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hydrogen bonds, ionic bonds, hydrophobic interactions, and van der Waals interactions
Strong covalent bonds called disulfide bridges may reinforce the protein’s structure as well |
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30. Be able to give at least two examples of proteins that have quarternary structure.
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Collagen is a fibrous protein consisting of three polypeptides coiled like a rope
Hemoglobin is a globular protein consisting of four polypeptides: two alpha and two beta chains |
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31. What causes sickle cell anemia (at the molecular level)?
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Sickle-cell disease, an inherited blood disorder, results from a single amino acid substitution in the protein hemoglobin.
Normal red blood cells are full of individual hemoglobin molecules, each carrying oxygen. Fibers of abnormal hemoglobin deform red blood cell into sickle shape. |
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32. What types of environmental factors cause proteins to denature?
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Alterations in pH, salt concentration, temperature, or other environmental factors can cause a protein to unravel or function inefficiently
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33. Know that once a protein is denatured it can rarely fold back again into its functional structure.
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This total loss of a protein’s native structure is called denaturation. A denatured protein is biologically inactive.
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34. Why so Siamese cats have dark “points” on their ears, nose, feet, and tails?
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??
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35. What ultimately controls what proteins an organism will make?
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The DNA
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37. Be able to draw out a nucleoside, a nucleotide, and a nucleotide triphosphate.
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Slide 82
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38. Be able to draw out a polynucleotide, showing the location of all the atoms (except those in the nitrogenous bases), the charges, and the 5’ and 3’ ends. What do “5’” and “3’” refer to?
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Slide 82
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39. In DNA, A pairs with ____ and C pairs with ____.
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G-C A-T
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40. What type of bonds holds the two strands of the double helix in DNA together?
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Adjacent nucleotides are joined by covalent bonds that form between the –OH group on the 3' carbon of one nucleotide and the phosphate on the 5' carbon on the next
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41. Know that the two strands in a double-stranded nucleic acid always run antiparallel to one another.
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In the DNA double helix, the two backbones run in opposite 5 → 3 directions from each other, an arrangement referred to as antiparallel
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42. How many genes are there in the human genome (approximately)? How many chromosomes are they spread out across?
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20k -25k genes
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