BIO 100 Exam 1 Study Guide - Santa Barbara City college

BIO 100 Exam 1 Study Guide - Santa Barbara City college Bio 100 - Exam 1 Study Guide Why does a plant create sugar rather than keep the stored energy as ATP? Glucose is more stable The Process of Science Dif ...

BIO 100 Exam 1 Study Guide - Santa Barbara City college Bio 100 - Exam 1 Study Guide Why does a plant create sugar rather than keep the stored energy as ATP? Glucose is more stable The Process of Science Difference between Hypothesis and Theory • Hypothesis - suggested explanation for an event, which can be tested • Theory - thoroughly tested and confirmed explanation for observations or phenomena What is a confounding variable? • A part of an experiment that can vary or change Atoms and Molecules What makes up an Atom? -protons, neutrons, electrons • Atom - basic unit of matter that cannot be broken down by normal chemical reactions • 2 Protons, 2 Neutrons in the nucleus and 2 Electrons surrounding the nucleus • Protons have positive charge, Neutrons have no charge, Electrons have negative charge • Atomic number is equal to the number of protons it has • Mass number is the number of protons and neutrons (since they have a mass of 1) What is a covalent bond? Ionic bond? Hydrogen bond? • Ionic bond - when an element donates an electron, it creates a positive ion, and accepting element is now negatively charged, since opposite charges attract, it creates a bond between ions • Covalent bond - when an electron is shared between two elements (nonpolar covalent bond = electron is shared equally, polar covalent bond = electron spends more time to one nucleus than the other • Hydrogen bond - weak bond, hydrogen atom in covalent bonds has slightly positive charge, so it attracted to neighboring negative charges • Van der Waals interactions - weak attractions/interactions between molecules What is a carbohydrate? • macromolecule in which the ratio of carbon to hydrogen to oxygen is 1:2:1; carbohydrates serve as energy sources and structural support in cells • Macromolecule, provides energy (glucose) to the body • Monosaccharide = simple sugars • Disaccharide = 2 monosaccharides undergo dehydration reaction • Polysaccharide = long chain of monosaccharides linked by covalent bonds • Starch = stored form of sugars in plants • Glycogen = storage form of glucose in animals • Cellulose = natural biopolymer (provide structural support for cell) What is a protein? • Organic molecules in living systems • May serve in transport, storage, or membranes, or toxins or enzymes • Enzymes - catalysts in biomechanical reactions, each enzyme is specific for the substrate • Hormones - chemical signaling molecules What is a monomer? What is a polymer? Examples - - - - - - - - - - - - What does the absorption of light do to chlorophyll? Where does the electron go? • Causes an electron in the chlorophyll to break free • It goes to a nearby electron acceptor What replaces the electron in the system and what are the products of that electron donation? • A molecule of water is split to replace the electron • Products are Oxygen and Hydrogen ions in the thylakoid space What are the light dependent reactions? • Convert light energy into chemical energy What are the light independent reactions- Calvin cycle? • Reactions of photosynthesis that uses energy from light dependent reactions to form glucose & other carbohydrate molecules What is RuBisCo? • Enzyme that catalyzes a reaction between Carbon Dioxide and RuBP What is photorespiration? • Explain the 2 different adaptations in some groups of plants that minimize photorespiration- C4, CAM. What is the interplay of leaf size, surface area for sunlight absorption, and water loss? • Leaf size is influenced by water availability • More surface area = more sunlight What are stomata and what enters and leaves the plant through stomata? • Small regulated openings • Carbon dioxide comes in, oxygen goes out