Topic 1: The Chemical Context of Life, Holtzclaw and Holtzclaw, 2014

Transcription

1 Name Block Topic 1: The Chemical Context of Life, Holtzclaw and Holtzclaw, Complete the vocabulary on a separate piece of paper. 2. What are the elements that make up most of living matter? What are some trace elements do organisms need? 3. Briefly review the structure of atoms. 4. Why are valence electrons important in chemical reactions? (Not in Holtzclaw) 5. Is the atomic mass of an ion different than the neutral atom? Why? 6. How do the isotopes of carbon differ from one another? Do they have different chemical properties? (Remember that chemical properties are determined by the electrons.) 7. Sodium has an atomic number of 11 and a mass number of 23. Explain what these numbers mean. How can you determine the number of neutrons? 8. Explain oxidation and reduction. These are important terms that we will be using throughout the year. (Not in Holtzclaw) a. oxidation b. reduction 9. Nonpolar covalent bonds electrons. Give an example. A. share, equally B. share, unequally C. transfer, equally D. transfer, unequally 10. Oxygen and nitrogen are highly electronegative. What is electronegativity? 1

2 11. Explain how polar covalent bonds form. Give an example. 12. How do atoms form ionic bonds? What results from an ionic bond? 13. How is a hydrogen bond different than a covalent bond? Circle all that apply. A. strong B. weak C. intramolecular (within a molecule) D. intermolecular (between molecules) 14. A molecule with polar covalent bonds would be. Circle all that apply. A. be soluble in water C. contains atoms that have partial negative or positive charge B. not be soluble in water D. contains atoms with very similar electronegativity 15. Draw five water molecules and show the hydrogen bonds between the molecules. Be sure to indicate which atoms are involved in the hydrogen bond, and make sure the hydrogen bonds are short and straight. 16. What is a chemical reaction? 17. Consider the overall reaction for photosynthesis shown below. a. Label which compounds are the reactants and which are the products. 6 CO H 2 O C 6 H 12 O O 2 b. Remember that oxygen is highly electronegative. Which molecules would you guess are polar? CO 2 H 2 O C 6 H 12 O 6 O 2 2

3 Water and its properties 1. Complete the vocabulary on a separate piece of paper. 2. The properties of water are in large part due to hydrogen bonds. Each water molecule can form (how many) hydrogen bonds. Why does water form hydrogen bonds? Use the terms electronegativity and polar covalent in your answer. 3. Why are each of the following properties of water important to living organisms? (Short free response) a. cohesion b. transpiration c. high specific heat d. solid ice is less dense than liquid water e. polarity leading to water as a medium for the metabolic processes of cells 4. The ph scale is a measure of the concentration of hydrogen ions. Explain why buffers, including carbonic acid, are important for maintaining homeostasis in animals. 5. Carbon dioxide plus water make carbonic acid. What would happen in the buffer system below if an animal had excess CO2 such as during exercise? Would blood ph be maintained within its required narrow ph range ( )? carbonic acid / bicarbonate blood buffer system 3

4 Carbon and the Molecular Diversity of Life 1. Complete the vocabulary on a separate piece of paper. 2. All organic compounds contain the element. 3. What are the major elements found in cellular molecules including carbohydrates, lipids, proteins, and nucleic acid? 4. Describe why carbon is so versatile and able to form so many different large and complex macromolecules. 5. What is an isomer? 6. The functional groups on a carbon skeleton determine the chemical behavior and function of large organic molecules. Complete the table below. Important Functional Groups in Organic Molecules Functional Chemical Organic compounds and notes group structure hydroxyl carboxyl carbonyl amino phosphate sulfhydryl methyl 7. Indicate the function groups in the following important organic molecules and circle the functional group on the diagrams on the next page. a. phospholipids b. amino acids (2 functional groups) c. ribose and deoxyribose on the 3 carbon d. tags on DNA 4

5 Macromolecules 1. Explain the dehydration reaction (dehydration synthesis). Fill in the box below with the appropriate compound in diagram A. 2. Explain hydrolysis. Fill in the box below with the appropriate compound in diagram B. 5

6 carbohydrates category structure examples function monosaccharide disaccharide polysaccharide (energy storage in plants) polysaccharide (energy storage in animals) polysaccharide (structural in plants) polysaccharide (structural in animals and fungi) 3. Lipids: Give the functions of the following lipids: a. fats b. waxes c. phospholipids d. cholesterol e. steroid hormones 6

7 f. Label the diagram of triglycerides with glycerol and fatty acids. Label each fatty acid with saturated, monounsaturated, or polyunsaturated. g. Label the diagram of a phospholipid with head, tail, hydrophilic, hydrophobic, and indicate the location of the phosphate group. 4. Proteins: Draw a labeled diagram of an amino acid in the box. Draw arrows to point to the two highly electronegative elements in this molecule. a. Label the bond between amino acids in the dipeptide below. What is the name of this covalent bond? How is this bond formed? 7

8 b. Describe the four levels of protein structure. Include the bonds that are involved. i. ii. iii. iv. c. Explain chaperonins: d. Explain denaturation (in Holtzclaw) and dissociation (not in Holtzclaw) 5. Nucleic acids: Draw a labeled diagram of a nucleotide in the box. a. Label the diagram of DNA with nucleotide, phosphodiester bond, hydrogen bond, sugar, phosphate group, base, 5 end, and 3 end. 8

9 Name Block Topic 2: The Cell, Holtzclaw and Holtzclaw, Label or draw in the major characteristics for the prokaryote and eukaryote cells. Label : plasma membrane cytosol Draw in the appropriate cells: ribosomes ( ) DNA ( ) nuclear membrane (-----) internal membranes (yes/no) 2. Complete the table Domains and Kingdoms Prokaryotes Eukaryotes Domain Kingdom 3. List the function and other important information for each of the following parts of eukaryotic cells. Part of the cell function and other important information plasma membrane nucleus ribosome smooth ER rough ER 9

10 Golgi apparatus lysosomes vesicles large central vacuole mitochondria chloroplasts peroxisome cytoskeleton microtubules microfilaments intermediate filaments centrosomes centrioles flagella cilia extracellular matrix tight junctions desmosomes gap junctions 10

11 cell wall plasmodesmata 4. Circle the organelles found in animal cells but not plants cell. Draw a box around the organelles found in plant cells but not animal cells. Do not do anything to organelles found in both. cell wall centriole chloroplast extracellular matrix large central vacuole lysosome mitochondrion plasmodesmata 5. The plasma membrane forms a boundary of a cell. Label the part of plasma membrane in the following diagram. 11