HW #16 - AP Biology Period 4 #22 Liem Nguyen 11/14/09...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
AP Biology Period – 4 #22 Liem Nguyen 11/14/09 Homework #16 (091120): Chapter 16 (due Friday 091120 ) Total points: 20 for Attempt on all questions ONE Concept Map: 10 points The Molecular Basis of Inheritance Objectives DNA as the Genetic Material 1. Explain why researchers originally thought protein was the genetic material. genes located on chromosomes DNA and protein are components of chromosomes became candidates for genetic material proteins were macromolecules, with functions for hereditary material T.H. Morgan’s group showed that genes are located on chromosomes. The two chemical components of chromosomes, DNA and protein, became the candidates for the genetic material. Proteins were originally thought as genetic material, because they were macromolecules with great heterogeneity and specificity of function, essential requirements for the hereditary material. 2. Summarize the experiments performed by the following scientists that provided evidence that DNA is the genetic material: a. Frederick Griffith b. Oswald Avery, Maclyn McCarty, and Colin MacLeod c. Alfred Hershey and Martha Chase d. Erwin Chargaff Griffith: transformation Avery, McCarty, MacLeod: transforming agent was DNA Hershey, Chase: nucleic acids are hereditary material for viruses Chargaff: 4 nitrogenous bases Griffith discovered transformation, a change in genotype and phenotype due to assimilation of external DNA by a cell. Avery, McCarty, and MacLeod discovered that DNA was the transforming agent. Hershey and Chase experimented and found that nucleic acids are the hereditary material for viruses. Chargaff discovered the four nitrogenous bases. 3. Explain how Watson and Crick deduced the structure of DNA and describe the evidence they used. Explain the significance of the research of Rosalind Franklin. Crick studied protein structure with X-ray crystallography Franklin: X-ray diffraction photograph of DNA DNA was helical, double helix
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Crick was an X-ray crystallographer. When he and Watson viewed Franklin’s X-ray diffraction photograph of DNA, they were able to know that DNA was a double helix, and deduce the width of the helix and spacing of nitrogenous bases. The structure of DNA was a double helix.
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 5

HW #16 - AP Biology Period 4 #22 Liem Nguyen 11/14/09...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online