Unit 1 : DNA Flashcards
4 stages of hypothesis for the formation of the 1st cell
- abiotic (non living) synthesis of small organic molecules
- small molecules into macromolecules
- packaging of molecules into protocells (prokaryotic cells)
- origin of self replicating molecules
Describe the Miller - Urey Experiment
they created an experiment to see if water vapor cooled our oceans and wanted to see what was in it and to see if it was possible that macromolecules could be formed
What is a protocell?
(lipids and other molecules?)
May have been fluid filled vesicle
- they lipids and other molecules can form vesicles formation
What can increase the rate of vesicle formation? What substrate?
adding clay can increase the rate of vesicle
What properties of life vesicles can exhibit?
- simple growth
- reproduction
- metabolism
- maintenance of internal environment
Why is RNA the 1st genetic material and not DNA?
Due to hypothesis protocells were able to form on earth and they grew and split and passed RNA to their “daughters” and RNA can replicate itself and not DNA
What catalyzes different reaction?
ribozymes
Why is it important that earth has a reducing atmosphere?
due to the lack of oxygen and other gases and vapors, which prevents oxidation,
What did morgans group showed ?
showed genes are located on chromosomes and made of DNA and held together by proteins.
How was the role of DNA 1st discovered?
discovered by studying bacteria and viruses that can infect them.
Griffith Experiment
- worked with two strains of bacteria (pathogenic, harmless)
- transformation: the strains could change it self
What did Avery, Mccarty, and MacLeod established?
20 years later they affirmed griffith experiment
- you can transform cells with just DNA and change behavior
Pathogenic vs. Harmless strains of bacteria
(Griffith Experiment)
(S strain) Pathogenic: smooth - body doesn’t recognize it (deadly) pneumonia
(R starin) Harmless: rough - body attacks it (not deadly)
Hershey - Chase
- they used viruses to see if it was protein or DNA, which has sulfur
- showed that DNA is the genetic material of the T2 phage (virus)
Double Helix
- franklin and wilkins discovered that DNA was a double helix
- franklin concluded that 2 sugar phosphate backbones with nitrogenous bases
Franklin, Watson, Cricket,
- franklin discovered double helix in DNA
- watson and cricket formed a model of double helix (leaked info from franklin)
Translation
mRNA
in cytoplasm
process in which the information encoded in a strand of mRNA is used to construct a protein
- where tRNA & mRNA work together to make polypeptide
happens in the cytoplasm and ribosomes are involved (eukaryotic cells)
Transcription
tRNA
in nucleous
making mRNA using info in DNA
- (DNA directed synthesis of RNA)
- strand of DNA is used as a template for the manufacture of a strand of pre-mRNA
Polypeptide
1 small bead from translation = 1 amino acids