Biology-S Open-Ended Review

Question 1 – Safety Rules Wear protective equipment including goggles, aprons, and gloves When using heat – always use tongs or heat gloves – never point heated objects towards people. Waft to smell unknowns No food or drink in the lab Carry and use sharp objects (scalpel or scissors) appropriately

Question 2 – Diffusion and Osmosis Osmosis – diffusion of water Hypertonic – more solute outside the cell, water gets sucked out Hypotonic – less solute outside the cell, water gets sucked in Isotonic – concentration of solute is equal on both sides Quick experiment – the gummy bear with the salt and plain water.

Question 3 – Cell Organelles Cell membrane – monitors materials into and out of the cell Active transport – move against a concentration gradient (pumps) Passive transport – no energy required to move molecules Facilitated diffusion (carrier proteins) Channels

Question 4 - Genetics Homozygous dominant – RR (red) Homozygous recessive – rr (white) Heterozygous – Rr (red) RR x RR (100% RR, 100% red) rr x rr (100% rr, 100% white) RR x rr (100% Rr, 100% red) Rr x Rr (25% RR, 50% Rr, 25% rr, 75% red, 25% white) RR x Rr (50% RR, 50% Rr, 100% red) rr x Rr (50% Rr, 50% rr, 50% red, 50% white)

Question 5 – Base pairing rules DNA to DNA A=T, C=G DNA to mRNA (creates codons) A=U, C=G mRNA to rRNA or tRNA (creates anticodons)

Question 5 – Determining amino acids Using the mRNA codon First letter = left side of table Second letter = top of the table Third letter = right side of the table

Question 5 – Protein Synthesis Two steps Transcription – mRNA copies DNA in the nucleus Translation – mRNA carries information to the ribosomes where rRNA and tRNA translate the mRNA to obtain amino acids and build proteins

Question 6 – Prokaryote v. Eukaryotes Prokaryotes No defined nucleus No membrane-bound organelles Believed to be earliest known cells Eukaryotes Well defined nucleus Membrane bound organelles Believed to have evolved from symbiotic prokaryotes

Question 7 – Well-designed experiment Control – something to compared against (can be positive or negative) Independent variable – variable that experimenter controls (example – time) Dependent variable – variable that the experimenter is collecting data on (example – growth of a plant)

Question 8 – Macromolecules Carbohydrates – used for energy Lipids – long term energy storage, protective coating (wax) Proteins – structure Nucleic acid – information storage

Question 9 – Ecological interactions Mutualism – everyone wins! All parties benefit (wrasse and pleny) Commensalism – I win, you are neither helped nor harmed (barnacles on a whale) Parasitism – I win, you lose! (tape worms, ring worms)

Question 10 – Food web Producers – photosynthetic organisms Primary consumers – herbivores Secondary consumers – carnivores Higher order consumers – top predators (humans, eagles, lions etc.)

Question 11 – Photosynthesis and Cellular Respiration 6CO2+6H2OC6H12O6+6O2 Reactants – carbon dioxide, water (in the presence of sunlight) Products – glucose and oxygen Cellular respiration C6H12O6+6O2 6CO2+6H2O Reactants – glucose and oxygen Products – carbon dioxide and water The products of photosynthesis “power” the process of cellular respiration which “powers” all the other processes that living things do!

Good Luck! If you paid attention during this review and you look these questions over a couple of times … You are prepared for the open-ended portion of the Biology-S exam! 12 questions  you pick 15. Budget your time accordingly on test day.