Lesson 1 Define biology o scientific study of life Life defies a simple one sentence definition Life is recognized by what living things do Some of the properties associated with life are Evolutionary adaptation Order Growth and development Response to Environment Reproduction Energy processing Regulation Describe the biological hierarchy o Life can be studied at different levels from molecules to the entire living planet o The study of life can be divided into different levels of biological organization o What are emergent properties Results from the arrangement and interaction of parts within a system Emergent properties characterize non biological entities as well Ex a functioning bicycle emerges only when all of the necessary parts connect in the correct way Ex Specific organization of molecules within the chloroplast allows for photosynthesis to occur If you mix all those molecules in a test tube photosynthesis will not occur Describe the essential components and functions of life o Every organism interacts with its environment including nonliving factors and other organisms them life s activities o Both organisms and their environments are affected by the interactions between Ex a tree takes up water and minerals from the soil and carbon dioxide from the air the tree releases oxygen to the air and roots help form soil o A fundamental characteristic of living organisms is their use of energy to carry out including moving growing and reproducing requires a source of energy o Work o Living organisms transform energy from one form to another Ex light energy is converted to chemical energy then kinetic energy Energy flows through an ecosystem usually entering as light and exiting as heat o Structure and function of living organisms are closely related Ex a leaf is thin and flat maximizing the capture of light by chloroplasts Ex the structure of a bird s wing is adapted to flight The cell is the lowest level of organization that can perform all activities required for life All cells o Are enclosed by a membrane o Use DNA as their genetic information A eukaryotic cell has membrane enclosed organelles the largest of which is usually the nucleus By comparison a prokaryotic cell is simpler and usually smaller and does not contain a nucleus or other membrane enclosed organelles o Chromosomes contain most of a cell s genetic material in the form of DNA deoxyribonucleic acid DNA is the substance of genes Genes parents to offspring multicellular organisms are the units of inheritance that transmit information from o The ability of cells to divide is the basis of all reproduction growth and repair of o Feedback mechanisms allow biological processes to self regulate Two types means that as more of a product accumulates the process Negative feedback that creates it slows and less of the product is produced Positive feedback that creates it speeds up and more of the product is produced means that as more of a product accumulates the process Define a hypothesis and use it o Is a tentative answer to a well framed question o A hypothesis must be testable and falsifiable o A scientific hypothesis leads to predictions that can be tested by observation or experimentation o How do you test a hypothesis Observation Your flashlight doesn t work Question Why doesn t your flashlight work Hypothesis 1 The batteries are dead Hypothesis 2 The bulb is burnt out Both these hypotheses are testable Know the difference between a theory and a hypothesis in scope than a hypothesis and can lead to new testable hypotheses o Broader o General o A theory is supported by a large body of evidence in comparison to a hypothesis State the different states and components of matter and how they are different from one another o Organisms are composed of matter o Matter is anything that takes up space and has mass o Matter can take several forms including Solids Liquids Gases State the main subatomic particles o Neutrons no electrical charge o Protons positive charge o Electrons negative charge o What is the atomic mass and number An element s mass number is the sum of protons plus neutrons in the nucleus approximates the atom s total mass atomic mass An element s atomic number is the number of protons in its nucleus o What is an isotope Isotopes are two atoms of an element that differ in number of neutrons Ex in carbon 14 14C there are 8 neutrons instead of 6 seen in carbon 12 12C State the difference between atomic number and mass number An element s mass number is the sum of protons plus neutrons in the nucleus approximates the atom s total mass atomic mass An element s atomic number is the number of protons in its nucleus Know the significance of electron orbitals o An orbital is the three dimensional space where an electron is found 90 of the time o Each electron shell consists of a specific number of orbitals The orbitals can be represented in a variety of ways Electron distribution diagram Separate electron orbitals Superimposed electron orbitals Lesson 2 Describe the different types of chemical bonds o Covalent bonds Ex O2 o Ionic bonds Ex NaCl o Hydrogen bonds Ex H2O to H2O interactions o Van der Waals interactions o List the chemical bonds in order of strength Strongest Weakest Covalent Ionic Chemical Hydrogen Van der Waals o What are the properties of covalent ionic hydrogen and Van der Waals interactions COVALENT IONIC HYDROGEN A covalent bond is the sharing of a pair of valence electrons by two atoms Atoms sometimes strip electrons from their bonding partners A hydrogen bond forms when a hydrogen atom covalently bonded to one electronegative atom is also attracted to another electronegative atom o Note A hydrogen bond is NOT the covalent bond that hydrogen has with another atom are attractions between molecules that are close together as a result of these charges Important in maintaining the structure of proteins and DNA VAN der WAALS List examples of each type of bond COVALENT o In a covalent bond the shared electrons count as part of each atom s valence shell A molecule consists of two or more atoms held together by covalent bonds IONIC H H o Atoms can convert to charged ions electrons in the outermost shell are unstable if unpaired with another electron Ex the transfer of an electron from sodium to chlorine o An ionic bond is an attraction between an anion and a cation o Compounds formed by ionic bonds are called ionic o Salts such as sodium chloride table salt are often found in compounds or salts nature
View Full Document
Unlocking...