Introduction Flashcards
1
Q
What is the proportion of human cells to bacteria in the 70kg “reference man”?
A
Human cells: 3.0 * 10^13
–> most erythrocytes
Bacteria: 3.8 * 10^13
Mass of bacteria: 0.2 kg
2
Q
What are the three domains of life?
A
Prokaryotes: Bacteria & Arachaea
Eukaryotes
3
Q
What is a genome?
A
- The sum of all inheritable genetic information of an organism that is stored in form of DNA (RNA).
- Consists of coding regions (genes) and intergenic sequences.
4
Q
What is a gene?
A
- Difficult to find a generally accepted definition!
- Typically: a gene is the unit of inheritance that is present in the form of DNA or RNA.
- Most often used: a gene is the segment of DNA (RNA) that encodes the information needed to synthesize a particular amino acid sequence of a polypeptide chain.
–> Problem: What about non-coding RNA genes? - More precise: a gene is the segment of DNA that encodes the information for one particular gene product (protein or ncRNA).
–> (Alternative) Splicing: is the definition of «one gene product» still valid? - Better/Alternative Definition: Genomic palimpset
Each gene is a system comprising a genomic region with corresponding network of control regions and ensemble of transcripts.
5
Q
What is an ORF?
A
Open Reading Frame
= the region of a DNA/mRNA, that actually carries the information required for translation; sequence between the start and the stop codon
