* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download HB Unit 1 Foundations of Biology
Introduction to evolution wikipedia , lookup
Synthetic biology wikipedia , lookup
Natural environment wikipedia , lookup
Biomolecular engineering wikipedia , lookup
Cell theory wikipedia , lookup
Cell (biology) wikipedia , lookup
Paleontology wikipedia , lookup
Photosynthesis wikipedia , lookup
State switching wikipedia , lookup
History of molecular biology wikipedia , lookup
Incomplete Nature wikipedia , lookup
Precambrian body plans wikipedia , lookup
Chemical biology wikipedia , lookup
Abiogenesis wikipedia , lookup
Evolutionary history of life wikipedia , lookup
Developmental biology wikipedia , lookup
History of biology wikipedia , lookup
Biochemistry wikipedia , lookup
Evolution of metal ions in biological systems wikipedia , lookup
Unit 1: Foundations of Biology Section 1: The World of Biology Section 2: Themes in Biology Section 3: The Study of Biology Section 4: Tools and Techniques Section 1: The World of Biology Biology= study of life. 7 characteristics of life include: 1. Organization and presence of cells 2. Response to stimuli 3. Homeostasis 4. Metabolism 5. Growth and development 6. Reproduction 7. Change through time Organization and Cells • Organization= a degree of order. • Cell= smallest unit of life. • Unicellular= organisms made up of one cell. • Multicellular= organisms made up of more than one cell. • Tissues= groups of cells that have similar abilities. • Organs= structures that carry out specialized jobs. Response to Stimuli • Stimulus= change in environment. • Response= reaction of an organism to a stimulus. Homeostasis • Homeostasis= the maintanence of a stable internal environment. Metabolism • Metabolism= sum of all chemical reactions necessary for life such as repair, movement and growth. Growth and Development • Growth results from the division and enlargement of cells. *cell division= formation of two cells from one • Development is the process by which organisms become more complex. Reproduction • Reproduction= production of new organisms; transmits hereditary information to offspring. • Asexual reproduction involves a single individual. • Sexual reproduction involves two individuals. * only trait of life not essential for the survival of the individual. Change Through Time • Evolution= ability of populations of organisms to change over a long period of time. *important for survival in the face of changing environmental conditions. Section 2: Themes in Biology The 3 Unifying themes found throughout Biology: 1. Diversity and unity of life: All life is connected by the genetic code; diversity results from descent through modification. -there are 3 major domains of organisms: Bacteria, Archaea and Eukarya Themes in Biology (cont’d) 2. Interdependence of organisms: All organisms interact with each other and with their nonliving environment. -ecology= study of organisms within their ecosystems. -ecosystem= communities of organisms and their physical environments. Section 3: Themes of Biology (cont’d) 3. Evolution of Life Populations of organisms change over time in the process of evolution. -natural selection= organisms with certain traits are better able to survive and reproduce -adaptation= trait that improves an individual’s ability to survive and reproduce. Section 3: The Study of Biology The scientific method is used to learn about the natural world; it includes the following steps: 1. Making observations 2. Asking questions 3. Forming a hypothesis; making a prediction 4. Testing the hypothesis through experimentation 5. Collecting and analyzing data from experiment 6. Drawing conclusion(s) from data 7. Communicating data to peers or public The Study of Biology (cont’d) • Only 1 question is investigated at a time. • Controlled experiments compare an experimental group (independent/tested variable) to a control group (no tested variable). *dependent variable= variable that is measured quantitatively (numbers) • Experiments can only disprove an hypothesis • Inference= conclusion drawn from facts and previous data, not on direct observation • Theory= set of related hypotheses; used to explain a large amount of data. Communicating Ideas May include presenting via: • Scientific journals • Scientific symposia Must be: • Peer reviewed • Based on actual experimentation • Free of bias In a scientific experiment, how many independent variables should be tested at the same time? A. none B. one C. two D. three or more Adam experiments with anole lizards that can change color, depending on their environment. Adam places a green anole lizard on a brown background and a brown anole lizard on a green background. Adam knows that the brown lizard should turn green and the green lizard should turn brown, but neither of the lizards changed color. What may have caused Adam’s results? A. Their color changing may be affected by something else besides the background color, such as fear or temperature. B. They may have to move to the new background on their own rather than being placed there. C. They may need more time in which to change color. D. The colors of the background may not have been appropriate for these lizards. A. Their color changing may be affected by something else besides the background color, such as fear or temperature. Unit 1: Chemistry of Life Section 1: Matter and Substance Section 2: Water and Solutions Section 3: Carbon Compounds Section 4: Energy and Metabolism • Atom: smallest unit of matter that maintains chemical properties of element • Electron (e-): charge • Proton: + charge • Neutron: neutral charge Atoms + + + + + + Elements • • • element: cannot be separated or broken down into simpler substances by chemical means stable elements have the same number of protons and electrons isotopes: atoms of the same element with different number of neutrons Bonding Goal of Atoms: 8 electrons in outer (valence) electron shell • • covalent bond: occur between elements that are close together on the periodic table; form molecules ionic bond: occur between metals and nonmetals; form compounds Polarity • • • Polar molecules have their charges distributed unequally. Polar molecules can dissolve polar molecules Nonpolar molecules can dissolve nonpolar molecules (why water dissolves so many things) Properties of Water 1) Floats as a solid (ice) • keeps rivers, ponds, oceans from freezing solid 2) Absorbs and retains heat • • Keeps the temperature of large bodies of water from changing too fast. Helps us maintain our internal temperature (homeostasis) 3) Water molecules stick to each other =cohesion 4) Attraction force between water and other substances =adhesion Solutions • • • • solution: two or more substances evenly dispersed within each other acid: solution with more hydronium (H3O+) ions than hydroxide ions base: solution with more hydroxide (OH-) ions than hydronium ions buffers help prevent changes in pH Composition of Living Matter Matter= anything that takes up space and has mass (including living things) 4 basic elements found in all life= carbon, hydrogen, oxygen and nitrogen Lipids Proteins Nucleic Acids Carbohydrates Lipids • • uses: long term energy storage, building block for cell membrane. ex: fats, waxes, steroids Proteins • uses: structure, support, communication, chemical reactions • made of amino acids • ability of a protein to function depends on its shape • Ex.s: enzymes, hormones. Enzymes • enzymes: proteins that act as catalysts (speed up chemical reactions) • substrate: the reactant that combines with the enzyme • active site: special shape on the enzyme that allows the substrate to fit on the enzyme • Lock and key/induced fit: model describing enzyme behavior Nucleic Acids • Uses: store and transmit genetic info; store energy • DNA: deoxyribonucleic acid; contains genetic info; made up of nucleotide units. • RNA: ribonucleic acid; important in protein synthesis (creation) • ATP: adenosine triphosphate; main energy unit for cells Carbohydrates • • uses: provides cell with nutrients for quick burn energy; building block for chiton and cellulose; ID’s specific cells. ex: sugar, starch, fiber Energy • energy: ability to move or change matter • Conservation of Mass: matter is neither created nor destroyed • Conservation of Energy: the total amount of energy in the universe does not change Chemical Reactions • • • • reactants: beginning participants in a chemical reaction products: formed in a chemical reaction activation energy: minimum energy needed to start a chemical reaction alignment: atoms must be correctly aligned for a reaction to occur ACTIVATION ENERGY and ALIGNMENT MUST be present for a reaction to occur.