Lecture 1 - Genome Expression Flashcards
What are the three primary branches on the tree of life?
-Bacteria (Eubacteria) -Archaea (Archaebacteria) -Eucaryotes
Archaea and bacteria are considered what type of cells?
Prokaryotes
What are the characteristics of a prokaryote?
- single-celled
- lack nucleus and organelles
These cells come together and form biofilms
Prokaryotes
What protects prokaryotes from outer conditions?
The cell wall
What are the characteristics of a eukaryote?
- single-celled or multicellular
- have nuclei and organelles
What is the function of the nucleus?
Houses the genetic material
What are the functions of organelles?
Helps with specific functions
Where does transcription occur in a prokaryote? Where does translation occur?
They both occur inside the same compartment, they occur at the same time.
Which of the two cells is larger?
Eukaryotes are much larger.
In what ways do eukaryotes differ structurally from prokaryotes?
Eukaryotes are compartimentalized.
What allows eukaryotes to change shape?
Extensive cytoskeletal network
Describe the endosymbiotic relationship
A predator would go around eating prokaryotes until one benefitted it. It became the mitochondria and chloroplast.
Name a phagocytic cell
Neutrophil
Describe a phagocytic cell
- Scavenges for bacteria
- Very fluid
- Changes shape using phagocytosis
What role does the genome play?
Encodes the information to construct and maintain an organism.
What make up genomes?
DNA (some viruses have RNA genomes)
How does the genome release the biological information stored?
It uses genome expression.
What is the FIRST product of genome expression?
The transcriptome.
Define the transcriptome
All the RNA molecules present in a cell at a particular time.
What does the transcriptome provide?
It provides a fingerprint for each type of gene.
What does the DNA Microarray allow us to do?
It can comapre the unknown transcriptome to all known cells and the similarities will help identify it. (Red are highly expressed and green are lowly expressed)
The transcriptome is maintained by what process?
Transcription
Explain what occurs during transcription.
RNA is synthesized (transcription) from DNA with the help of RNA polymerase. DNA is transcribed into RNA.
What is the SECOND product of genome expression?
The proteome
Define the proteome
The collection of proteins in a cell
What do the proteins affect in the cell?
They define the biochemical functions in the cell (metabolic reactions)
When do we use 2D gel electrophoresis?
It is used to compare the protein compositions in two different cells.
Which technique does the following graph represent?
DNA Microarray
-comparison of transcriptomes (genes)
Which of the following techniques is depicted in the graph below?
2D gel electrophoresis
-comparison of protein compositions
The proteome is maintained by which process?
Translation
Explain the process of translation.
RNA is translated into a protein (protein synthesis) by a ribosome.
What is the central dogma?
Genome (DNA) –> Transcriptome (RNA) –> Proteome (protein)
How do the different cell types of multicellular organism compare?
They all have the same genome.
How are different cell types produced within an organism?
They have the same genome but differences in genome expression. They express different subsets of genes to get different shapes and functions.
Why aren’t all genes expressed at the same time?
It is not energetically favourable.
