Cellular control Flashcards
1
Q
transcriptional level
A
- alters the rate of transcription
- creation of mRNA
- controlled by transcription factors
- e.g lac operon
2
Q
post transcriptional
A
- mRNA can be edited by removing introns from exons
- makes mature mRNA
- by splicing
3
Q
body plans
A
- general structure if an organism
- coded for by Hox genes
4
Q
transcription factors
A
- proteins that bind to specific DNA sequences
- control the rate at which particular genes are transcribed
- e.g activators ad repressors
5
Q
Homeobox sequences
A
- highly conserved
- can be lethal if changed
- other genes can be effected if homeobox is altered
- regulatory gene
- codes for homeodomain
6
Q
Hox genes
A
- controls the development of body plan
- have regions called homeobox sequences
7
Q
homeodomains
A
- bind to specific sites on DNA enabling the protein to work to transcription factors
8
Q
Apoptosis
A
- programmed cell death
- enzymes in cell break down the cell components
- the cell shrinks and begins to fragment
- phagocytes engulf and digest the cell fragments
- respond to internal and external stimuli (internal= DNA damage, external = stress)
9
Q
mitosis
A
- development of body plan
- creates the bulk of the body parts
- growth and repair of tissues
- production of stem cells
- asexual reproduction
- respond to internal and external stimuli (internal= DNA damage, external = stress)
10
Q
regulatory gene
A
- makes repressor proteins / transcription factors
- controls the expression of a structural gene
11
Q
structural gene
A
- makes enzymes/proteins
12
Q
introns
A
- not translated
- not part of mature mRNA
- don’t affect the survival of a species
- non-coding part of DNA
13
Q
post -translational modification (cAMP)
A
- binds to protein on cell membrane
- changes tertiary structure
- alters the shape of active site making it more or less active
- is a secondary messenger
- activates proteins within the cell to causes a chain of reactions (adrenaline)
14
Q
histone modification
A
- DNA coils around histones as they are positively charged and DNA is negatively charged
- tightly bound = less likely to transcribe
- loosely bound =more likely to be transcribed
