Chapter 1: Cells and Genomes Flashcards
How many genes are in the human genome?
25,000-30,000
About how many base pairs are in the human genome?
3.1 billion
By how many base pairs would two random humans differ?
1-2 bp per 1000 bps
How many genes are present in the bacterium Mycoplasm genetalium?
521 genes
About how many genes are the absolute minimum required for a functional cell/organism?
~300
About how many genes are conserved across EVERY organism?
60 genes
What are 4 reasons why multicellular life exists?
- information transfer
- cell specialization/efficiency
- predation/survival
- energy conservation
What are three reasons why warm-blooded multicellular life exists?
- pathogen protection
- enzyme efficiency
- niche-filling
What are 4 ways we get genetic changes?
- mutations
- gene duplication
- DNA segment shuffling
- horizontal transfer
What method of genetic change is the most ‘influential’? why?
gene-duplication; allows for ‘back-up’ copies to continue coding
What are the two types of homolog?
- orthologs
- paralogs
This is a mutation that occurs in one line of gene replication that allows for divergence and speciation of the whole organism
ortholog
This is a mutation that occurs after gene duplication occurs; usually causes new gene formation WITHIN a species
paralog
about how large (in diameter) is an average cell?
30-40 um
Why can’t eukaryotic cells grow infinitely large?
rate of diffusion and total surface area on protein rate of reaction
What are 4 reasons why we use model organisms?
- short generation times
- comparable systems
- low cost
- small with large generation size
What is one limitation of using model organisms to assume data about other systems?
some interactions/characteristics may be species-specific; making them obsolete
What are 3 reasons why is C. elegans used?
- model multicellular eukaryote
- have only 1000 cells (experience eutely)
- 2-3 week lifespans
What are 3 reasons why Sarcomyces cervisiae is used?
- can reproduce in multiple ways
- short generation times
- Model single-cell eukaryote
This is the scientific belief that membrane-bound organelles like mitochondria and chloroplasts were originally phagocytized before being integrated into the cell.
Endosymbiotic hypothesis
The entire E. coli genome encodes for how many protein?
4289
