The Genome and its Transmission Flashcards
What is the transcriptome?
The complete set of RNA transcripts.
What is the proteome?
The complete set of proteins produced.
List 4 examples of RNA that are not translated into proteins.
1 & 2 - rRNA and tRNA are involved in the translation of mRNA.
3 - snRNA is involved in modifying other RNA molecules.
4 - miRNA binds to mRNA to inhibit translation.
What is satellite DNA?
Repeated sequences of nucleotides.
What type of DNA is found at centromeres?
Heterochromatin containing satellite DNA.
List 2 differences between heterochromatin and euchromatin.
1 - Euchromatin is transcriptionally active whereas heterochromatin is not.
2 - Heterochromatin stains darker than euchromatin.
What is the function of telomeres?
To protect the end of the chromosome from deterioration or from fusion with neighboring chromosomes.
List 3 roles of repeated sequences of DNA.
1 - Formation of telomeres.
2 - Formation of centromeres.
At which stage of mitosis does chromatin condensation begin?
Prophase.
At which stage of mitosis does spindle assemble outside the nucleus?
Prophase.
What is a kinetochore?
The section of the centromere to which microtubules of the spindle attach.
What is a nucleolus?
When are they present?
- The site of rRNA transcription in the nucleus.
- They appear during interphase and reappear at telophase.
What mediates cytokinesis?
A contractile ring of actin and myosin.
What are chiasmata?
The point on a bivalent at which crossing over and exchange of genetic material occur.
List 4 sources of variation.
1 - Mutation.
2 - Random mating.
3 - Random fertilization.
4 - Crossing over between chromatids of homologous chromosomes during meiosis.
