General Introduction Flashcards
1
Q
How does information evolve? (And self-organizes)
A
- Evolution by natural selection
- from an origin different forms of evolved lives are created via natual selection
- Cultural evolution
- from a self-conscious organism (doesn’t know how they work)
- encodes informations, makes tools and invenctions
- Computer evolution (in the future)
- man made
- can self-improve
- self-conscious machines that know how they work
2
Q
how does evolution occur?
A
- Natural selection
- Starting from a population, a selection according to some fitness criteria of only some elements occurs, after that the selected population is amplified and some variations are indoduced
3
Q
What is the relationship between life and information?
A
- life is based on a natural mechanism by which information is able to organize itself
- entities with a program are a part of life
- the program respond to some inputs with an action according to a set of rules (knowledge)
- a program (and knowledge) can be associated with negative entropy
- any entity that is driven by a complex program has something to do with life: either it is living or it was created by something living
4
Q
Trifonov paper
A
- Attempts in giving a general definition of life according to several vocabulary definitions
- Analyzes 123 definitions to find the most defining terms for a concise and inclusive definition: Life is self-reproduction with variations
5
Q
What is biology?
A
- study of Life
- different from life, extratterestial life goes beyond biology
- life can be studied at different scales and granularity, from molecules to organisms
- each branch has a different scope of study: interactions, reactions, behaviours
6
Q
What is Informational Biology
A
- Investigates strong link between Life and Information
because Life is based on a “natural” mechanism by which information isable to organize itself - adaptable to the scope, uses information to make sense and comprehend what is happening during biological phenomenon
- technical terms may have different meaning depending on the context that they are used (Epistemology, the study of knowledge)
7
Q
Shannon work on Information
A
- Covers the concept of Informations. He has founded information theory.
- mainly concern about communication that is the
transfer of information from a source to a destination - developed information entropy as a measure of the information content in a message (measure of uncertainty)
8
Q
What is the central dogma?
A
- it’s an explanation of the flow of genetic information within a biological system
- that once “information” has passed into protein it cannot get out again
- DNA-> DNA, DNA -> RNA; RNA-> Protein
- transfer from protein to protein, or from protein to nucleic acid is impossible, precise determination of sequence
9
Q
DNA
A
- Double stranded
- 4 nucleotides: A, C, G, T
- replicates itself thanks to DNA polymerase [enzyme, protein] (DNA-> DNA)
- double helix model proposed by Watson and Crick, 1953
10
Q
RNA
A
- Singlestranded
- 4 nucleotides: A, C, G, U
- is transcripted from genes
- Stop codon is sequence UGA
- transcripted thanks to RNA polymerase [enzyme, protein] (DNA ->RNA)
11
Q
Protein
A
- Translated from RNA
- Single stranded
- 20 total aminoacids
- translated with Ribosomes (RNA -> Protein)
12
Q
What is needed for evolution?
A
- Enzymes, proteins (DNA polymerase and RNA polymerase)
- Ribosomes (complex machineries made of RNA+proteins)
- are part of the “hardware” required to run the genetic program
- information is coded in the DNA, is the software [tRNA]
- Metabolites (dNTP’s, NTP’s, amino acids)
- Energy (ATP) [previously not self-synthetizable]
- Happens under certain conditions
13
Q
tRNA
A
- family of RNAs, decods information in DNA sequence [using mRNA]
- task: transferring on the ribosome the amino acid that corresponds to the next codon that is to be decoded
- accepted by the ribosome only if the codon [DNA] and anticodon [tRNA] are complementary
- specific for one aminoacid [aptamers]
- specific enzymes rechanrge the tRNA with the corresponding aminoacid
14
Q
Miller and Urey experiment
A
- published 1953 at the University of Chicago
- explain the availability of metabolites
- simulated early earth conditions, tested for chemical origins of life [abiogenesis]
- idea: conditions favored chemical reactions that synthesized organic compounds from inorganic
15
Q
RNA world
A
- hypothetical stage in the evolutionary history of life on Earth, in which self-replicating RNA molecules proliferated before the evolution of DNA and proteins
- RNA was both hardware and software
- To process DNA to RNA to Proteins, many proteins are required. At the beginning how could the process start without them? Why RNA is quite involved in the process (mRNA, tRNA)? [Bartel & Szostak 1993]