L15: How do genes make cells? Flashcards
What is the percentage of protein, lipids and carbohydrates in a typical human cell?
50% protein, 40% lipids and 10% carbohydrates
What are the different categorisations of what makes a cell?
Building blocks, macromolecules, supramolecular assemblies and organelles
This determines when and in what cells a gene is transcribed to produce mRNA. It is the first step determining how many individual proteins are produced in a cell.
Transcriptional control
What does the central dogma state?
That the encoding of information only goes one way.
How DNA is transcribed into mRNA then RNA translated into a protein.
True or false. Not every cell has the same DNA and the same ~21000 protein coding genes.
False. Remember cells replicate uniformly- so it would be the same across every cell.
Approximately how many genes are expressed in all cells for basic cellular functions?
10,000 genes
How many genes in the cell are unique to a specific cell type? These genes make the brain cell different from the heart cell.
about 1000-2000 genes
This is the process where a DNA sequence is copied into an RNA molecule.
Transcription
When is a gene said to be expressed or turned on?
When it is transcribed
These are proteins binding to a specific DNA sequence and control the rate of transcription.
Transcription factors
What are the key elements (in terms of regions) of a gene?
Regulatory region and transcribed region
What elements of the gene are found in the regulatory region?
Promoter, RNA polymerase, Activators, Repressor, transcription factors
This is the DNA sequence at which transcription factors bind and recruit RNA polymerase.
Promoter
True or false. The promoter determines if and how much a gene is transcribed.
True.
True or false. The promoter contains short sequences that transcription factors bind to.
True
This is the region where sequences of DNA are copied into RNA.
Transcribed regions
Which region does the end genes, exons and introns belong in?
Transcribed regions
This is the process of intron removal.
Splicing
How do transcription factors control transcription? How can a gene be expressed through this?
Through activators and repressors. A gene can only be expressed when both activator transcription factors are present and if the repressor is absent,
What controls the activity of the RNA polymerase?
Transcription factors
True or false. Transcription can occur fully with one activator and a repressor.
False. Transcription cannot occur with the repressor.
True or false. Only a little bit, but mostly no transcription can occur with one activator and no repressor.
True.
Where are the transcription factors of the insulin gene made?
Only in Pancreatic B cell (no other place)
The transcription factors in a liver cell are only found where?
In cells that make glycogen.
True or false. Transcription factor can control the activity of genes, as well as hormones.
True (remember insulin is a hormone)
