Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
**Molecular Set 1
Exam 1
| Question | Answer |
|---|---|
| What is a description of Molecular biology | It is a ‘hybrid” discipline that combines elements of genetics and biochemistry |
| what is the study of molecular biology? | the study of gene structure and function at the molecular level |
| what was the earliest work of molecular biology could not be considered of? | molecular biology or molecular genetics |
| what was the earliest work on genes termed? | transmission genetics |
| what does transmission genetic deal with | dealt with the transmission of traits form parent organisms to their offspring. |
| what does molecular biology include the study of? | DNA/RNA structure and function DNA replication transcription and translation mechanisms gene structure/function/control of expression gene cloning, genomics, proteomics and bioinformatics |
| how did Gregor Mendel influence transmission genetics | concluded that inheritance was "particulate" |
| what does particulate mean? | each parent contributed particles (genetic units, genes) to the offspring |
| how did Thomas Morgan influence transmission genetics | predicted that gametes would contain only one allele of each gene instead of two. |
| what are gametes? | sex cells |
| if chromosomes carry the genes,____ | then chromosome number should be reduced by half in the gametes. |
| what is the theory of Morgan | Chromosome Theory of Inheritance (CTOI) |
| what else did Morgan discover in regards to fruit flies and provided evidence for CTOI? | eye-color in fruit flies are sex-linked. |
| what is sex-linked gene | transmission along with the sex to the offspring. |
| how did morgan assume genes are arranged? | in a linear manner on chromosome. |
| what did morgan know during the process of meiosis? | crossing over between two homologou chromosome could occur. . |
| what is the result of meiosis | the result is an exchange of genes between 2 homologous chromosomes |
| further apart two genes are on a chromosome, | the more likely they are to recombine |
| closer two genes are on a chromosome | the more likely they are not to recombine |
| A.H Sturtevant | predicted that a mathematical relationship exists between the distance separating two genes on a chromosomes and the frequency of recombination between those two genes |
| who created created genetic mapping techniques? | A.H Sturtevant |
| if 2 loci recombine with a frequency of 1% how far apart are they? | they are separated by a map distance of 1 CENTIMORGAN |
| Barbara McClintock | provided a direct physical demonstration of recombination corn chromosomes. |
| what scientist provided evidence for Sturtevant's work? | Barbara McClintock |
| what is molecular genetics? | describes what genes are made of and how they function |
| miescher | found that cell nuclei contained a mixture of compounds that he named NUCLEIN |
| what it first major component of nuclein | Deoxyrubonucleic Acid (DNA) |
| by the 1800's DNA and RNA were well known to be what? | polymers of nucleotides |
| what is a nucleotide? | composed of a sugar, phosphate group and nitrogenous base. |
| how are polymers formed | sugars linked together through their phosphate groups by phosphodiester bonds. |
| what is the second major component of nuclein | protein |
| what is protein | are polymers of amino acids linked together by amide bonds |
| what was the early thinking of chromosomes' composition | has to be composed of some kind of polymer, as this fit with the concept that genes were all lined up along the length of the chromosome. |
| what were the three choices that were candidates for the genetic material | DNA, RNA or protein |
| McCarty | demonstrated that DNA was the genetic material of inheritance by transforming experiment similar to an experiment by Griffith |
| Griffith experiment | demonstrated that transformation has occurred during the exp. This laid the foundation for eventually identifying DNA as the genetic material |
| what was the organism that Griffith used during his exp. | Streptococcus pneumoniae |
| how did griffith grow his strands? | on agar |
| how did griffith classify his strands | of appearance |
| what were the type of strains he exp with | smooth strain (S), rough strain (R), heat-killed S strain, a mix of R strain and heat-killed S strain. |
| describe smooth strain | S strain- smooth in appearance, symmetric colonies of cells with capsules. |
| what happen if the S strain was injected into the mice? | they died |
| why did the mice with an injection of S strain die | because the capsule of the S strain was used as a protectant against the mouse's immune system. |
| describe Rough strain | R strain- colonies were rough and irregular in morphology with no capsule. |
| what happen if the mouse was injected with R strain | the mouse would live. |
| why did the mice live when injected with the R strain | because there was no capsule to protect the strain and therefore the mouse's immune system was able to detect and destroy the pathogen. |
| describe heat-killed S strain | heat was introduced to a normal S strain. this destroyed the capsule and killed the strain. |
| what happen when the mouse was injected with a heat-killed S strain | the mouse lived. |
| why did the mice live when injected with a heat-killed S strain | the capsule was destroyed and therefore the mouse's immune system was able to detect and destroy the strain. |
| describe the mix with R strain and heat-killed S strain | regular rough strain mixed with heat-killed smooth strain |
| what happen when the mice were injected with the mix of strains? | they died |
| why did the mice die when they were injected with the mix | because there was a transformed of genetic material with the two strains |
| what question was griffth not able to answer | the chemical nature of the gene |
| how did McCarty be able to demonstrate that DNA was the genetic material | 1. Removed protein from test extract and extract still retained transforming ability. 2. Digested test extract with various enzymes until one showed desired results. |
| what were the various enzymes that were used by McCarty | a. Tripsin (still transformed) b. Chymotrypsin (still transformed) c. RNase (still transformed) d. DNase (didn’t transform, made it evident that DNA is the cause) |
| what are the physical-chemical analysis of the purified "transforming substance" used | 1. Ultracentrifugation 2. Electrophoresis 3. UV absorption spectrophotometry 4. Chemical analysis nitrogen to phosphorus ratio |
| what was determined by the Ultracentrifugation | MW estimation |
| what was determined by the Electrophoresis | high motility due to high charge-to-mass ratio DNA |
| what was determined by the UV absorption spectrophotometry | absorption spectrum matched that of DNA 260nm |
| what was determined by the chemical analysis nitrogen to phosphorous ratio | ratio of 1.67. Protein contamination would raise the N to P ratio. |
| Edwin Chargaff | most known for his work with base pairing found that bases are not found in equal proportions and base composition carried between species varied. |
| Rollin Hotchkiss | extended Avery's work Purified transforming material so that it contained only 0.02% protein. Also showed that genetic traits OTHER that R and S could be transferred by DNA. |
| Hershey-Chase expt | The T2 bacteriophage (bacterial virus) was used in these experiments. The phage genes enter the host cell and direct the synthesis of new phage particles. they looked if the genes reside in the DNA or the protein by using radioactivity genes are in |
| what is a phage | composed of only DNA and protein |
| what is the difference in the protein and DNA of a phage | Contents of phosphorous and sulfur There is A LOT of P in DNA and no S. There is A LOT of S in phage protein and no P. |
| descirbe the steps in the Hershey-Chase expt | Phage DNA was radiolabeled with phosphorous-32(32P) Phage protein was radiolabeled with sulfur-35 (35S) |
| Protein coat is labeled with specifically with 35S | • Attachment of pahge to host cells • Removal of phage coats by blending • Cell containing little 35S-labeled protein, plus unlabeled DNA |
| DNA is labeled with specifically 35P | • Attachment of phage to cost cells • Removal of phage coasts by blending • Cells contained lots of 32P-labeled DNA |
| who discovered the structure of DNA | Rosalind |
| Watson and Crick | published the double-helical model of DNA structure |
| genes with in viruses are sometimes made up of | RNA |
Created by:
kort
Popular Biology sets