Chapter 2 PowerPoint PDF

Inorganic Compounds (8 of 12) Acids – Electrolytes that dissociate (ionize) in water and release hydrogen ions – Proton donors – Example: – Strong acids ionize completely and liberate all their protons – Weak acids ionize incompletely Copy...

Inorganic Compounds (8 of 12) Acids – Electrolytes that dissociate (ionize) in water and release hydrogen ions – Proton donors – Example: – Strong acids ionize completely and liberate all their protons – Weak acids ionize incompletely Copyright © 2021 Pearson Education, Inc. All Rights Reserved Inorganic Compounds (9 of 12) Bases – Electrolytes that dissociate (ionize) in water and release hydroxyl ions – Proton acceptors – Example: Copyright © 2021 Pearson Education, Inc. All Rights Reserved Inorganic Compounds (10 of 12) Neutralization reaction – Type of exchange reaction in which acids and bases react to form water and a salt – Example: Copyright © 2021 Pearson Education, Inc. All Rights Reserved Inorganic Compounds (11 of 12) pH – pH measures relative concentration of hydrogen (and hydroxide) ions in body fluids – pH scale is based on the number of protons in a solution – pH scale runs from 0 to 14 – Each successive change of 1 pH unit represents a tenfold change in concentration Copyright © 2021 Pearson Education, Inc. All Rights Reserved Inorganic Compounds (12 of 12) pH – Neutral ▪ 7 is neutral ▪ Neutral means that the number of hydrogen ions exactly equals the number of hydroxyl ions – Acidic solutions have a pH below 7 ▪ More – Basic solutions have a pH above 7 ▪ Fewer – Buffers—chemicals that can regulate pH change Copyright © 2021 Pearson Education, Inc. All Rights Reserved Figure 2.12 The pH Scale and pH Values of Representative Substances Copyright © 2021 Pearson Education, Inc. All Rights Reserved Organic Compounds (8 of 26) Lipids – Most abundant are the triglycerides, phospholipids, and steroids – Contain carbon, hydrogen, and oxygen ▪ Carbon and hydrogen outnumber oxygen – Insoluble in water, but soluble in other lipids Copyright © 2021 Pearson Education, Inc. All Rights Reserved Organic Compounds (9 of 26) Triglycerides, or neutral fats – Found in fat deposits – Source of stored energy – Composed of two types of building blocks—fatty acids and one glycerol molecule ▪ Saturated fatty acids ▪ Unsaturated fatty acids Copyright © 2021 Pearson Education, Inc. All Rights Reserved Figure 2.15a Lipids Copyright © 2021 Pearson Education, Inc. All Rights Reserved Organic Compounds (10 of 26) Fatty acid chains of triglycerides – Saturated fats ▪ Contain only single covalent bonds ▪ Chains are straight ▪ Exist as solids at room temperature since molecules pack closely together – Unsaturated fats ▪ Contain one or more double covalent bonds, causing chains to kink ▪ Exist as liquid oils at room temperature ▪ “Heart healthy” Copyright © 2021 Pearson Education, Inc. All Rights Reserved Figure 2.16a Examples of Saturated and Unsaturated Fats and Fatty Acids Copyright © 2021 Pearson Education, Inc. All Rights Reserved Figure 2.16b Examples of Saturated and Unsaturated Fats and Fatty Acids Copyright © 2021 Pearson Education, Inc. All Rights Reserved Organic Compounds (11 of 26) Trans fats – Oils that have been solidified by the addition of hydrogen atoms at double bond sites – Increase risk of heart disease Omega-3 fatty acids – Found in cold-water fish and plant sources, including flax, pumpkin, and chia seeds; walnuts and soy foods – Appear to decrease risk of heart disease Copyright © 2021 Pearson Education, Inc. All Rights Reserved Organic Compounds (12 of 26) Phospholipids – Contain two fatty acids chains rather than three; they are hydrophobic (“water fearing”) – Phosphorus-containing polar “head” carries an electrical charge and is hydrophilic (“water loving”) – Charged “head” region interacts with water and ions while the fatty acid chains (“tails”) do not – Form cell membranes Copyright © 2021 Pearson Education, Inc. All Rights Reserved Figure 2.15b Lipids Copyright © 2021 Pearson Education, Inc. All Rights Reserved Organic Compounds (13 of 26) Steroids – Formed of four interlocking rings – Include cholesterol, bile salts, vitamin D, and some hormones – Some cholesterol is ingested from animal products; the liver also makes cholesterol – Cholesterol is the basis for all steroids made in the body Copyright © 2021 Pearson Education, Inc. All Rights Reserved Figure 2.15c Lipids Copyright © 2021 Pearson Education, Inc. All Rights Reserved Organic Compounds (16 of 26) Protein structure – Polypeptides contain fewer than 50 amino acids – Proteins contain more than 50 amino acids – Large, complex proteins contain 50 to thousands of amino acids – Sequence of amino acids produces a variety of proteins Copyright © 2021 Pearson Education, Inc. All Rights Reserved Organic Compounds (17 of 26) Structural levels of proteins – Primary structure—strand of amino acid “beads” – Secondary structure—chains of amino acids twist or bend ▪ Alpha helix—resembles a metal spring ▪ Beta-pleated sheet—resembles pleats of a skirt or sheet of paper folded into a fan – Tertiary structure—compact, ball-like (globular) structure – Quaternary structure—result of a combination of two or more polypeptide chains Copyright © 2021 Pearson Education, Inc. All Rights Reserved Figure 2.18a The Four Levels of Protein Structure Copyright © 2021 Pearson Education, Inc. All Rights Reserved Figure 2.18b The Four Levels of Protein Structure Copyright © 2021 Pearson Education, Inc. All Rights Reserved Figure 2.18c The Four Levels of Protein Structure Copyright © 2021 Pearson Education, Inc. All Rights Reserved Figure 2.18d The Four Levels of Protein Structure Copyright © 2021 Pearson Education, Inc. All Rights Reserved Organic Compounds (20 of 26) Enzymes – Act as biological catalysts – Increase the rate of chemical reactions – Bind to substrates at an active site to catalyze reactions – Can be recognized by their –ase suffix ▪ Hydrolase ▪ Oxidase Copyright © 2021 Pearson Education, Inc. All Rights Reserved Figure 2.20 A Simplified View of Enzyme Action Copyright © 2021 Pearson Education, Inc. All Rights Reserved Organic Compounds (21 of 26) Nucleic acids – Form genes – Composed of carbon, oxygen, hydrogen, nitrogen, and phosphorus atoms – Largest biological molecules in the body – Two major kinds: ▪ DNA ▪ RNA Copyright © 2021 Pearson Education, Inc. All Rights Reserved Organic Compounds (22 of 26) Nucleic acids are built from building blocks called nucleotides Nucleotides contain three parts 1. A nitrogenous base ▪ A = Adenine ▪ G = Guanine ▪ C = Cytosine ▪ T = Thymine ▪ U = Uracil 2. Pentose (five-carbon) sugar 3. A phosphate group Copyright © 2021 Pearson Education, Inc. All Rights Reserved Figure 2.21ab Structure of DNA Copyright © 2021 Pearson Education, Inc. All Rights Reserved Organic Compounds (23 of 26) Deoxyribonucleic acid (DNA) – The genetic material found within the cell’s nucleus – Provides instructions for every protein in the body – Organized by complementary bases to form a double-stranded helix – Contains the sugar deoxyribose and the bases adenine, thymine, cytosine, and guanine – Replicates before cell division Copyright © 2021 Pearson Education, Inc. All Rights Reserved Figure 2.21d Structure of DNA Copyright © 2021 Pearson Education, Inc. All Rights Reserved Organic Compounds (24 of 26) Ribonucleic acid (RNA) – Carries out DNA’s instructions for protein synthesis – Created from a template of DNA – Organized by complementary bases to form a single-stranded helix – Contains the sugar ribose and the bases adenine, uracil, cytosine, and guanine – Three varieties are messenger, transfer, and ribosomal RNA Copyright © 2021 Pearson Education, Inc. All Rights Reserved Organic Compounds (25 of 26) Adenosine triphosphate (ATP) – Composed of a nucleotide built from ribose sugar, adenine base, and three phosphate groups – Chemical energy used by all cells – Energy is released by breaking high-energy phosphate bond Copyright © 2021 Pearson Education, Inc. All Rights Reserved Figure 2.22 ATP—Structure and Hydrolysis Copyright © 2021 Pearson Education, Inc. All Rights Reserved Organic Compounds (26 of 26) ADP (adenosine diphosphate) accumulates as ATP is used for energy ATP is replenished by oxidation of food fuels Three examples of how ATP drives cellular work are shown next Copyright © 2021 Pearson Education, Inc. All Rights Reserved Figure 2.23 Three Examples of How ATP Drives Cellular Work Copyright © 2021 Pearson Education, Inc. All Rights Reserved