Historical perspective Flashcards
How can we define genetics ?
Study of the origin, transmission and expression of genetic information
What is selective breeding ?
Artificial selection and breeding of natural genetic variants found in the wild
What is the cell theory and who developped it ?
Schleiden and Schwann
They found that:
- A cell is the basic structural, functional and biological unit of organism
- A cell is the smallest unit of life
- Cells derive from pre-existing cells
- All organisms are made of cells
What are the 3 factors necessary for evolution through natural selection to happen ?
- The traits need to be hereditary
- They need to have some variants
- They need to provide a fitness advantage (selection)
Which theory Sutton and Boveri came up with ?
Chromosomal theory of inheritance : chromosomes carry the genetic information
What mistake was in Sutton’s theory ?
He thought the first division of meiosis was equational and the second one reductional, but it’s the opposite
What is synapsis ?
Pairing of homologous chromosomes during meiosis
Who and How did we find out the 3D structure of DNA ?
Rosalind Franklin (stolen by Watson and Crick)
found by X-ray diffraction
Place in chronological order the following events:
- Avery, MacLeod, McCarty exprience
- 3D structure of DNA
- PCR
- Mendel
- Cell theory
- Genome editing
- Evolution through natural selection
- chromosomal theory of inheritance
- Structure and functions of ribosomes
- Cell theory (1838)
- Evolution through natural selection (1859)
- Mendel (1866)
- Chromosomal theory of inheritance (1902)
- Avery, MacLeod, McCarty expirement (1944)
- 3D structure of DNA (1953)
7.DNA sequencing technologies (1980) - PCR (1983)
- Structure and function of ribosomes (2009)
- Genome editing (2020)
Where can the genetic material can be found in cells ? Which form does it take ?
Found in the nucleus, in the mitochondria and in the chloroplast
In prokaryotes, the chromosomes are in circular form
In eukaryotes, the chromosomes are in linear form
What differentiates DNA from RNA ?
DNA : hydrogen group on 2’
RNA : hydroxyl group on 2’
Between RNA and DNA, which molecule is more stable?
DNA
How many hydrogen bonds are between A and T
How many between C and G ?
2 between A and T
3 between C and G
What are other names for the coding strand ?
- Sense strand
- Positive-sense
- Positive (+) strand
- Watson strand
What are other names for the noncoding strand ?
- Anti-sense
- Crick strand
Complete : The Watson strand’s 5’-end is located on the chromosome’s ___ arm
Short (p)
Complete : the Crick strand’s 5’-end is located on the chromosome’s ___ arm
Long (q)
The p-arm and q-arm refer to what ?
p-arm : short arm of a chromatid
q-arm : long arm of a chromatid
True or false: the coding sequence of genes can either be on the Watson or on the Crick strand
True
what are chromosomes made of ?
Chromatin (DNA molecule wrapped around histone proteins)
What is the total length of the human DNA molecule ?
2 meters
Why are histones positively charged ?
Because they contain a lot of positively charged amino acids
Because DNA is slightly negative
Define Heterochromatin and Eurochromatin
Heterochromatin: Condensed form of chromatine, not available from transcription
Eurochromatin: less condensed form of chromatin, available for transcription
In what form is found most of the chromatin during interphase ?
Eurochromatin (90%)
