Worksheetsmolecular biology
Total questions: 10
Worksheet time: 10mins
Chromosomes were first observed by ______ in 1848 in the nuclei of pollen mother cells of Trandescantia
Hofmeister
Waldeyer
Anthony
Michaelis
_______ are filamentous or thread like or rod shaped bodies present in the nucleus
Nucleolus
Chromosomes
Genes
Mitochondria
How does the organization of chromatin differ between euchromatin and heterochromatin?
Euchromatin is found only in prokaryotes, while heterochromatin is found in eukaryotes.
Euchromatin and heterochromatin have the same level of transcriptional activity but differ in their DNA sequence.
Euchromatin is loosely packed and transcriptionally active; heterochromatin is tightly packed and transcriptionally inactive.
Euchromatin is tightly packed and transcriptionally inactive; heterochromatin is loosely packed and transcriptionally active.
What is the function of linker histones in chromatin?
Linker histones are involved in DNA replication only.
Linker histones help organize and compact chromatin, stabilizing nucleosome structure and regulating gene expression.
Linker histones prevent any form of gene expression.
Linker histones are responsible for protein synthesis in the cell.
What are the components of a nucleosome?
Histone proteins (H1, H2A, H3) and RNA
Histone proteins (H2A, H2B, H3, H4) and DNA.
DNA and lipids
RNA and ribosomes
How does the nucleosome core particle contribute to DNA compaction?
The nucleosome core particle allows DNA to remain completely unwrapped.
The nucleosome core particle increases the length of DNA strands.
The nucleosome core particle prevents DNA from folding altogether.
The nucleosome core particle compacts DNA by wrapping it around histone proteins, reducing its length and facilitating further folding.
What role do topoisomerases play during DNA replication?
Topoisomerases repair DNA damage after replication.
Topoisomerases act as helicases to unwind DNA.
Topoisomerases synthesize new DNA strands during replication.
Topoisomerases relieve torsional strain and prevent supercoiling during DNA replication.
What is the primary function of histones in DNA packaging?
To replicate DNA during cell division.
To provide energy for DNA synthesis.
The primary function of histones in DNA packaging is to condense and organize DNA into chromatin.
To protect DNA from environmental damage.
Describe the structure of a nucleosome.
A nucleosome consists of two DNA strands intertwined.
A nucleosome is a single strand of RNA.
A nucleosome is made up of a lipid bilayer surrounding DNA.
A nucleosome consists of DNA wrapped around a histone octamer, composed of eight histone proteins.
