bscs$biology$midyear$review$ - msjuo2011 -...
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BSCS Biology Midyear Review
2011-‐2012 Ms. Juo
Exam Schedule
Monday, January 23rd Period 1 (8:30-‐10am) D block: Room 258 E block: Room 260
Midyear Review Packet
Due: Just before you are handed the exam (1st period, 8:30am)
Late Policy: NO LATE PACKETS will be accepted after the exam has been handed out. There is NO LATE CREDIT.
What: Choose the 20 most difficult (for you) questions. Staple your TYPED answers to the back of the midyear review packet. You can earn up to 20 points extra credit towards your HW grade.
ENGAGE AND NATURAL SELECTION Unit 1
ScienNfic Method
1. Observe a problem 2. Make a hypothesis 3. Perform an experiment 4. Analyze data 5. Make a conclusion 6. Repeat or publish
Leaf collecNon/ Footprints
• Making good observaNons • Types of data:
– QuanNtaNve – measurable – QualitaNve – descripNve
• ObservaNons/evidence – things that you can actually observe
• Inference – reasonable assumpNons based on data and prior knowledge
Lab 1-‐2: Thinking as a ScienNst Thinks
• Making good observaNons! • Coming up with good quesNons based on observaNons
• Controlled experiments – make sure you only change one variable (the one you’re interested in)
Journal 1-‐2: Modeling Earth’s History
• Earth formed – 4.6 billion years ago
• Then came first life (bacteria) -‐ 3.5 billion years ago
• Hominids weren’t around unNl 6.5 million years ago
• How do we know all of this? – Fossils and radioacNve daNng
Journal 1-‐3: I Know Beans… • OverpopulaNon – organisms reproduce unNl they outnumber resources
• CompeNNon – too many organisms compete for those limited resources
• Variety – individuals are born with different traits • SelecNon – some individuals are beder at finding resources or surviving than others
• ReproducNon – the ones that “win” the compeNNon get to mate and reproduce (passing good traits to offspring)
• Specia&on – a+er a long &me, individuals may form new species if they are different enough from others
Journal 1-‐3: I Know Beans… (cont’d) • Natural SelecNon – Survival of the fidest in nature; DifferenNal reproducNon
• ArNficial SelecNon – WE choose who we want to reproduce (it has nothing to do with survival) – Dog breeding – Farming (bigger/beder corn)
Journal 1-‐4: VariaNon Within a Species
• All individuals within a species have differences – Physical (length of femur, e.g.) – Chemical (more efficient enzymes, e.g.)
• This is ESSENTIAL for natural selecNon to take place…
• Natural selecNon can only act on traits that are already present
• Different traits appear because of random mutaNons in the DNA
Lab 1-‐3: Bacterial AnNbioNc Resistance
• Some bacteria are already resistant to an anNbioNc
• The anNbioNcs will kill all bacteria but the resistant strains
• The resistant strains survive and reproduce, so they are more numerous in the next generaNon
Journal 1-‐5: EvoluNon in AcNon • The overuse of anNbioNcs has increased the number of resistant strains
• The bacteria populaNon has evolved!!
Case Study: I’m Looking Over a White Striped Clover
• Different varieNes of clover survive beder depending on the condiNons (Natural SelecNon!)
• Plain – Nonpoisonous (survive cold, die from predaNon)
• White-‐striped – Poisonous (die with cold, predators avoid)
ECOLOGY Unit 2
Journal 2-‐1: InteracNons in the World Around Us
• Levels of organizaNon
• AbioNc factors are nonliving factors
• BioNc factors are living factors
Pond Life
• Microscope use • Pond organisms – interacNons between predator (Daphnia) and prey (euglena, amoeba, roNfers) and producers (spirogyra, euglena)
Journal 2-‐2: Mystery on Easter Island
• OverpopulaNon and overuse of resources caused Easter Island populaNon to die
• LogisNc Growth (S-‐curve) – slow growth unNl the populaNon reaches carrying capacity
• ExponenNal Growth (J-‐curve) – Rapid growth (doubling) that may exceed carrying capacity and crash
Journal 2-‐3: Energy, Inc
• Producers convert the sun’s energy to chemical energy (food)
• Consumers eat producers or other consumers to get energy and nutrients
• An organism uses 90% of energy the energy it gets from eaNng – it is ‘lost’
• Only 10% of an organism’s energy is passed to the next level
• Energy does NOT get recycled! The sun replenishes lost energy
Lab 2-‐2: Owl Pellets
• Food webs – all food chains in a parNcular community
• Smaller populaNons as you go up the food chain – Each owl needs lots of mice – Each mouse needs lots of grass/seeds
• Ecological Pyramids – Pyramid of numbers (pop.) – Pyramid of energy – Biomass pyramid
Vocab: Symbiosis and InteracNons
• CompeNNon between species • PredaNon (+/-‐) – hunNng, killing, and eaNng prey
• Symbiosis – two organisms living together – Mutualism (+/+) – Commensalism (+/0) – ParasiNsm (+/-‐)
EutrophicaNon
• EutrophicaNon – Excess nutrients cause unlimited growth of algae in a lake
– Algae overpopulate and die, so bacteria populaNons grow as they consume dead algae
– OverpopulaNng bacteria use all oxygen in lake
Journal 2-‐4: Ecology Case Studies
• We examined science in the real world, with predicNons, experiment design, and data analysis
• We learned that humans and nature can change ecosystems
• Kermit (chemicals in water) • Sea Oders (overhunNng changed food web) • Iguanas (environmental change & populaNon collapse)
BIOCHEMISTRY AND DIGESTION Unit 3
Journal 3-‐1: How are atoms arranged?
• Organic compounds: Proteins, Carbohydrates, Nucleic Acids, Lipids
• Monomer vs. Polymer • DehydraNon synthesis • DegradaNon hydrolysis
Lab 3-‐1: What is in the food you eat?
• PosiNve control group – shows what a posiNve result looks like
• NegaNve control groups – show that your results aren’t due to some other unrelated factor
• Animal products contain protein • Plant products contain starch
Journal 3-‐2: CalculaNng Nutrients in Fast Food
• There are some nutrients and vitamins in fast foods…
• Fast foods alone cannot provide you with a balanced diet
Journal 3-‐3: Enzyme Structure and FuncNon
• Enzymes… – Are biological catalysts – Speed up reacNons in the body
– Lower acNvaNon energy – Only fit one substrate in their acNve site
– Are reusable – Are affected by pH and temperature
Journal 3-‐4: Protein Folding
• Proteins are made of amino acids
• Protein shape is determined by which amino acids it contains
• Primary Structure – sequence of amino acids • Secondary and TerNary Structure – folding of the chain
• Quaternary Structure – two or more chains together
Journal 3-‐4: Protein Folding
Lab 3-‐2: Enzyme Lab
• Catalase is found in plant and animal cells • Catalase has an opNmum pH and temperature • Outside a specific pH or temperature range, the enzyme denatures (changes shape) and the substrate can’t fit into the acNve site.
Oxygen Water PeroxideHydrogen catalase +!! "!
Glucose Demo
• Importance of controls • Saliva contains amylase (an enzyme that breaks starch into glucose)
• We break down our food into monomers, absorb them, then use them to build the materials we need (biosynthesis)
DigesNon Video/ Chart/ Diagrams
• Mouth – mechanical (teeth) and chemical digesNon (amylase – carbs)
• Esophagus – long tube (peristalsis)
• Stomach – mechanical (muscles) and chemical digesNon (pepsin – proteins)
DigesNon Video/ Chart/ Diagrams
• Small IntesNne – chemical digesNon (carbs, proteins, and lipids!) and absorpNon of nutrients – Pancreas (secretes enzymes into intesNne)
– Liver/Gallbladder (makes bile for fat digesNon)
• Large IntesNne – Absorbs water and holds bacteria (that make vitamins)
INTERNAL ENVIRONMENT OF ORGANISMS
Unit 4
Journal 4-‐1: Can you stand the heat?
• Homeostasis – keeping the internal environment constant
• We have to monitor – Temperature – pH – Nutrient levels (like blood sugar)
– Blood pressure
Lab 4-‐1: Cells in AcNon
• Eggs: Water moves in and/or out to maintain homeostasis
• Dialysis tube: Membranes are selecNvely permeable (only let iodine through)
• Plant cell: Water moves in and/or out to maintain homeostasis
Bubble Membranes
• Cell membranes are selecNvely permeable – They allow through small, hydrophobic things – They stop larger, hydrophilic, or charged things
• Transport proteins help substances through that otherwise wouldn’t be allowed
Journal 4-‐2: Membranes and Transport
• Membrane structure • Diffusion – movement down a gradient using no energy – Simple diffusion – Facilitated diffusion – Osmosis – water diffusion
• Dynamic Equilibrium
Journal 4-‐2: Membranes and Transport
• Osmosis – Water moves when the solute can’t – Water moves towards the area of more solute
Journal 4-‐2: Membranes and Transport
• AcNve Transport – Needs energy – Usually goes up a gradient
• Protein pumps • Endocytosis • Exocytosis
Lab 4-‐2: Cell Size and Diffusion
• Cells must remain small – As a cell gets bigger it needs more nutrients – The cell’s surface area doesn’t get big enough fast enough
– A large cell can’t get enough nutrients – Think of heat vents in this room and the gym…
Journal 4-‐4: Cells Alive
• Prokaryotes – Simple, bacterial cells – No membrane-‐bound organelles (including nucleus)
• Eukaryotes – Plants, animals, fungi, proNsts – Membrane-‐bound organelles are present
• Both have DNA, cell membrane, ribosomes, and cytoplasm
Journal 4-‐5: Cells Alive -‐ Organelles
Plant Cell Animal Cell
Journal 4-‐5: Cells Alive -‐ Organelles • Organelles:
– Nucleus – Nucleolus – Cell Membrane – Cytoplasm – Ribosome – Mitochondria – Vacuole – Golgi Body – Rough ER – Smooth ER – Lysosome – Cell Wall – Chloroplast – Centriole
Journal 4-‐6: RegulaNng the Internal Environment
• Homeostasis • Respiratory System – gas exchange (alveoli & capillaries)
• DigesNve System – brings in nutrients (villi & capillaries)
• Urinary System – gets rid of wastes (nephron & capillaries)
• Circulatory System – transports gas, nutrients, wastes
Journal 4-‐6: RegulaNng the Internal Environment
• Circulatory System – Transports materials – Structure and funcNon of the heart