QUIZ ANSWERS

Figure 1-10a The Ventral Body Cavity and Its Subdivisions POSTERIOR ANTERIOR Pleural cavity Thoracic cavity Pericardial cavity Diaphragm Peritoneal cavity Abdominopelvic cavity Abdominal cavity Pelvic cavity 2

Abdominopelvic Cavity Figure 1-9 Relationships among the Subdivisions of the Ventral Body Cavity Ventral Body Cavity • Provides protection • Allows organ movement • Linings prevent friction Subdivides during development into Thoracic Cavity Abdominopelvic Cavity Surrounded by chest wall and diaphragm Peritoneal Cavity Extends throughout abdominal cavity and into superior portion of pelvic cavity Right Pleural Cavity Mediastinum Left Pleural Cavity Surrounds right lung Contains the trachea, esophagus, and major vessels Surrounds left lung Abdominal Cavity Pelvic Cavity Contains many digestive glands and organs Contains urinary bladder, reproductive organs, last portion of digestive tract Pericardial Cavity Surrounds heart 3

2-9 Carbohydrates Monosaccharides Disaccharides Polysaccharides Simple sugars with 3 to 7 carbon atoms Glucose, fructose, galactose Disaccharides Two simple sugars condensed by dehydration synthesis Sucrose, maltose Polysaccharides Many monosaccharides condensed by dehydration synthesis Glycogen, starch, cellulose

2-11 Proteins Enzyme Function Enzymes are catalysts Proteins that lower the activation energy of a chemical reaction Are not changed or used up in the reaction Enzymes also exhibit: Specificity — will only work on limited types of substrates Saturation Limits — by their concentration Regulation — by other cellular chemicals

2-13 High-Energy Compounds Nucleotides Can Be Used to Store Energy Adenosine diphosphate (ADP) Two phosphate groups; di- = 2 Adenosine triphosphate (ATP) Three phosphate groups; tri- = 3 Phosphorylation Adding a phosphate group to ADP with a high-energy bond to form the high-energy compound ATP Adenosine triphosphatase (ATPase) The enzyme that catalyzes the conversion of ATP to ADP

2-10 Lipids Steroids Four rings of carbon and hydrogen with an assortment of functional groups Types of steroids: Cholesterol Component of plasma (cell) membranes Estrogens and testosterone Sex hormones Corticosteroids and calcitriol Metabolic regulation Bile salts Derived from steroids

2-3 Chemical Reactions Decomposition Reaction (Catabolism) Breaks chemical bonds AB A + B Hydrolysis A-B + H2O A-H + HO-B Synthesis Reaction (Anabolism) Forms chemical bonds A + B AB Dehydration synthesis (condensation reaction) A-H + HO-B A-B + H2O

Figure 3-7 Protein Synthesis Protein released into cytoplasm Smooth ER Ribosome DNA Rough ER mRNA Cytoplasm Nucleus Transport vesicle Nuclear pore

Figure 3-13 The Process of Translation The mRNA strand binds to the small ribosomal subunit and is joined at the start codon by the first tRNA, which carries the amino acid methionine. Binding occurs between complementary base pairs of the codon and anticodon. NUCLEUS mRNA Amino acid Small ribosomal subunit KEY tRNA Adenine Anticodon tRNA binding sites Guanine Cytosine Uracil Start codon mRNA strand

Figure 3-13 The Process of Translation The small and large ribosomal subunits interlock around the mRNA strand. Large ribosomal subunit

Figure 3-13 The Process of Translation A second tRNA arrives at the adjacent binding site of the ribosome. The anticodon of the second tRNA binds to the next mRNA codon. Stop codon

Figure 3-13 The Process of Translation The first amino acid is detached from its tRNA and is joined to the second amino acid by a peptide bond. The ribosome moves one codon farther along the mRNA strand; the first tRNA detaches as another tRNA arrives. Peptide bond

Figure 3-13 The Process of Translation The chain elongates until the stop codon is reached; the components then separate. Small ribosomal subunit Completed polypeptide Large ribosomal subunit