Biology

Ch. 7 Tour of the Cell 2007-2008 Light Microscope - LM ? Uses visible light ? inexpensive ? live or dead objects ? Resolution: ? As magnification ?, resolution ?. ? ~1000X. ? Limitations: ? many cell structures too small Just magnified 64X Magnification & Resolution Light Microscope Variations ? Unstained ? Stained: ?Methylene blue ? iodine Light Microscope Variations ? Fluorescence: uses dyes to make parts of cells ?glow?. ? Phase-contrast: enhances contrasts in density. ? Confocal: uses lasers and special optics to focus only narrow slides of cells. Electron Microscopes ? Use beams of e- ? Invented in 1939 ? Advantages: ?Much higher mag. ? 50,000X ? Disadvantages: ? Vacuum.

Name: ____________________________________________________ Date: _____ Period: ____ ? PAGE \* MERGEFORMAT ?1? AP Biology: Immune System WebQuest In this webquest, you will explore how the human body protects itself from invaders through three lines of defense. You will be going to different websites to see videos, animations, and images and to read explanatory text that will give you information that you will need in order to answer a series of questions about the immune system and how it works. Type your answers to the following questions. Be sure to write in your own words and use complete sentences. Go to this website:

AP BIOLOGY SEMESTER 2 REVIEW UNIT 7 CONTINUED: ANIMAL FORM & FUNCTION Cell Communication Reception ? signal molecule binds to receptor protein in cell membranes causing it to change shape G protein coupled receptor Transduction = cascade of molecules activates relaying signal within cell Signal transduction pathway (ex. G-protein, tyrosine-kinase receptors, ion channel receptors) Phosphorylation cascades Secondary messenger system (ex. Cyclic AMP, Ca2+ ions, DAG, IP3) Response Transcription factors turn genes on or off Cellular activity activate enzymes, open cell membrane channels, apoptosis Scaffolding proteins Endocrine System (table page 961) Homeostasis Blood sugar regulation, blood calcium regulation Negative feedback, positive feedback Neurosecretory cells

Bio II DiGennaro Hardy-Weinberg Practice Problems A population of rabbits may be brown (the dominant phenotype) or white (the recessive phenotype). Brown rabbits have the genotype BB or Bb. White rabbits have the genotype bb. The frequency of the BB genotype is .35. What is the frequency of heterozygous rabbits? 0.484 What is the frequency of the B allele? 0.59 What is the frequency of the b allele? 0.41 A hypothetical population of 10,000 humans has 6840 individuals with the blood type AA, 2860 individuals with blood type AB and 300 individuals with the blood type BB. What is the frequency of each genotype in this population? AA = 0.684 / AB = 0.286 / BB = 0.03 What is the frequency of the A allele? 0.827 What is the frequency of the B allele? 0.173

Ch. 7 Tour of the Cell 2007-2008 Light Microscope - LM ? Uses visible light ? inexpensive ? live or dead objects ? Resolution: ? As magnification ?, resolution ?. ? ~1000X. ? Limitations: ? many cell structures too small Just magnified 64X Magnification & Resolution Light Microscope Variations ? Unstained ? Stained: ?Methylene blue ? iodine Light Microscope Variations ? Fluorescence: uses dyes to make parts of cells ?glow?. ? Phase-contrast: enhances contrasts in density. ? Confocal: uses lasers and special optics to focus only narrow slides of cells. Electron Microscopes ? Use beams of e- ? Invented in 1939 ? Advantages: ?Much higher mag. ? 50,000X ? Disadvantages: ? Vacuum.