How is genetic material organised in eukaryotes compared to prokaryotes?
Eukaryotic genetic material is contained within a nucleus, while prokaryotic genetic material is arranged in the cytosol in a nucleoid region.
How is transport regulated in the eukaryotic nucleus?
Entrance and exit of material into and out of the nucleus is tightly controlled.
How dense are prokaryotic genomes?
Prokaryotic genomes are usually very dense, with around 90% protein-coding genes and about 10% regulatory sequences such as promoters and operators.
How much of the eukaryotic genome is protein-coding
Only around 1–2% of the eukaryotic genome is protein-coding
What interrupts protein-coding genes in eukaryotes?
Eukaryotic protein-coding genes are interrupted by non-coding stretches called introns.
What happens to introns and exons during mRNA processing?
Introns are spliced out of the transcript, while exons are retained.
Why does splicing increase protein diversity?
Different combinations of exons can be included or excluded, generating novelty and complexity from the same set of genes.
Why is splicing useful in multicellular organisms?
It allows additional regulatory regions and flexible gene regulation needed for multicellular complexity.
How do prokaryotic and eukaryotic chromosomes differ in structure?
Prokaryotic chromosomes are typically circular, while eukaryotic chromosomes are linear.
How do histones differ between prokaryotes and eukaryotes?
Eukaryotic DNA is associated with histones, whereas prokaryotic DNA generally is not.
How many genome copies are typical in prokaryotes vs eukaryotes?
Prokaryotes usually have one copy, while eukaryotic cells typically have two copies.
How does RNA polymerase differ between domains of life?
Eukaryotic RNA polymerase works differently from prokaryotic RNA polymerase, and archaeal RNA polymerase is more similar to the eukaryotic version.
How is gene regulation generated in eukaryotes?
Through transcription factors rather than different sigma factor subunits as in prokaryotes.
What type of cell division do prokaryotes use?
Binary fission.
What are the characteristics of binary fission?
It is simpler and quicker than mitosis, is a form of asexual reproduction, and produces two identical daughter cells.
Why is meiosis important in eukaryotes?
Meiosis enables genetic novelty and sexual reproduction.
What are the advantages compartmentalisation for biological processes
It allows a broader set of biological processes to occur simultaneously - due to being seperate
How does compartmentalisation enable specialisation?
Different compartments can take on specialised roles depending on their balance and function.
Why must some biological processes be kept separate?
Some processes would be inhibited if they occurred in the cytosol.
Why is concentration important for some cellular reactions?
Some reactions require high local concentrations of factors that are achieved through compartmentalisation.
How does compartmentalisation protect the cell?
It isolates potentially harmful processes or molecules from the rest of the cell.
What is the main function of the nucleus?
It contains most of the genetic information in eukaryotic cells.
Where else is genetic information stored in eukaryotes?
In mitochondria and chloroplasts.
What is the nuclear lamina?
A structure that provides important anchoring points for chromosomes.
