Chapter 2 – Water, Biochemistry, and Cells

Ch. 1 Review One hypothesis states that eating chicken noodle soup is an effective treatment for colds. Which of the following results does this hypothesis predict? a. people who eat chicken noodle soup have shorter colds than do people who do not eat chicken noodle soup b. people who do not eat chicken noodle soup experience unusually long and severe colds c. cold viruses cannot live in chicken noodle soup d. people who eat chicken noodle soup feel healthier than do people who do not eat chicken noodle soup

Ch 1. Review There is a strong correlation between obesity and the occurrence of a disease known as type 2 diabetes-that is, obese individuals have a higher instance of diabetes than nonobese individuals do. Does this mean that obesity causes diabetes? Explain.

Chemistry in Biology

Properties of Living Organisms Maintain Homeostasis (constant internal environment with a changing external environment): Growth Movement Reproduction Response to external stimuli Metabolism Breakdown of chemicals to produce energy Synthesis of chemicals Excretion of wastes

Water: Essential to Life Components of Water 2 hydrogen atoms, 1 oxygen atom Polar: positive hydrogen side and negative oxygen side Allows to dissolve substances like salt Properties of Water Facilitates chemical reactions Cohesive Moderates temperature https://www.youtube.com/watch?v=aVmU3CLxvgU

Atomic Structure & Chemical Bonding Atoms have protons (+) & neutrons (o) in their nucleus Electrons (-) have are located outside the nucleus and travel in orbitals Atoms have valence electrons on their outer orbital

Types of Bonds Covalent: atoms share electrons Ionic: attraction of charged atoms by similar, opposite charges Hydrogen: weak bond that forms when a partially positive hydrogen atom is attracted to a partially negative atom

Carbon in Living Organisms Organic Chemistry: branch of chemistry that is concerned with complex carbon-containing molecules Carbon has the ability to create bonds with up to four other elements

Macromolecules Protein Carbohydrates Lipids Nucleic Acids https://www.youtube.com/watch?v=H8WJ2KENlK0

Structure and Function of Carbohydrates Chemical composition – carbon, hydrogen, & oxygen with a 1:2:1 ratio Monosaccharides (sugar) are the monomer, disaccharides have 2 monosaccharides, & polysaccharides have more than 1 Function: Source of energy (ATP energy is produced) Structure – cell wall in plants & exoskeleton in insects

Structure and Function of Protein Contain an amino group (NH2+) and carboxyl group (COO-) Monomer is an amino acid Function: Structure in cytoskeleton in animal cells Movement in muscle cells Regulate chemical reactions via enzymes

Structure and Function of Lipids Contain a glycerol and fatty acid tail (hydrocarbons made out of a chain of hydrogen and carbon) Function: Fats store energy within living organisms Steroids chemical signaling and aid in membrane fluidity Phospholipids are the basic component of the cell membrane

Structure and Function of Nucleic Acids Monomer are nucleotides Nucleotides consist of a sugar, phosphate, and base Types of bases include uracil (RNA only), adenine, thymine (DNA only), cytosine, & guanine Types of sugars include deoxyribose in DNA and ribose in RNA Function: RNA synthesizes proteins DNA stores genetic information

Cell Structure & Function https://www.youtube.com/watch?v=cj8dDTHGJBY

Structure and Function of the Cell Membrane Made out of a phospholipid bilayer Contains proteins that aid in transport, structure, and communication Fluid Mosaic: Function: Regulates what goes in and out of the cell Semi-permeable: some substances cross and prevent others from crossing

Cell Organelle Functions Protein Production Nucleus: contains genetic information on how to make a protein Ribosome: makes the protein Rough Endoplasmic Reticulum: location of ribosomes Transport Rough Endoplasmic Reticulum: packs proteins in a vesicle Golgi Apparatus: sorts, modifies, packs, and ships proteins Lysosome: breaks down wastes or defective proteins for recycling or elimination out of the cell Cell Membrane: regulates what goes in and out of the cell

Cell Organelle Functions Energy Production Mitochondria: creates ATP energy from glucose Chloroplast: converts sun energy into glucose (chemical energy)

Properties of Prokaryotic Cell No membrane-bound organelles No nuclei Unicellular organisms Contain ribosomes, cell membrane, cell wall, & cytoplasm Cell walls made of peptidoglycan

Properties of Eukaryotic Cells Contain nuclei Membrane-bound organelles Contain cell membrane, cell wall, cytoplasm, ribosomes, Golgi Apparatus, Rough & Smooth Endoplasmic Reticulum, Mitochondria, Chloroplast, & Lysosome