answer stringlengths 1 239 ⌀ | question stringlengths 1 25.7k |
|---|---|
whether a particular region of DNA is accessible for gene expression | What does the manner of DNA storage on the histone and the chemical modifications of the histone itself regulate? |
regions where DNA replication is initiated to make two copies of the chromosome | What are replication origins? |
Telomeres | Long stretches of repetitive sequence that cap the ends of the linear chromosomes are called what? |
bacteria and archaea | What are prokaryotes? |
on a single large, circular chromosome | How do prokaryotes store their genomes? |
a remnant circular chromosome with a small number of genes | What type of chromosome do some eukaryotic organelles contain? |
plasmids | Small circles of DNA that encode only a few genes and are transferable between individuals are called what? |
horizontal gene transfer | What allows genes for antibiotic resistance to be passed between individual cells? |
prokaryotes | What type of organism has relatively gene dense chromosomes? |
eukaryotes | Regions of DNA that serve no obvious function are often found in what type of organism? |
DNA without an identified function | What is referred to as "junk DNA"? |
barely 2% | What percentage of the human genome is made of protein coding DNA? |
about 80% | What percentage of bases in the human genome are expressed by protein coding DNA |
often only a small part | Often, how large a part of the structure of a gene is the protein coding sequence? |
the actual protein coding sequence | What often plays only a small part in the structure of a gene? |
DNA regions that are not transcribed | What is one of the many elements that the structure of a gene consists of? |
untranslated regions of the RNA | What is another element of the structure of a gene? |
DNA regions that are not transcribed as well as untranslated regions of the RNA | What elements does the structure of a gene consist of? |
a regulatory sequence | What do all genes contain that is required for their expression? |
by transcription factors and RNA polymerase | How is a promoter sequence recognized? |
messenger RNAs (mRNA) that differ in how far they extend in the 5' end | What results when genes have more than one promoter? |
bind the transcription machinery well | What does a "strong" promoter sequence do? |
bind poorly and initiate transcription less frequently | What does a "weak" promoter sequence do? |
by binding to transcription factors | How do regulatory regions act? |
the DNA to loop | What happens when a regulatory region binds to transcription factors? |
by binding an activator protein | How do enhancers increase transcription? |
helps to recruit the RNA polymerase to the promoter | What happens after an enhancer binds an activator protein? |
silencers bind repressor proteins | What causes DNA to be less available for RNA polymerase? |
untranslated regions | What is at both ends of the transcribed pre-mRNA? |
untranslated regions | Where are the ribosome binding site, terminator and start and stop codons located on transcribed pre-mRNA? |
untranslated introns | What do most eukaryotic open reading frames contain? |
The sequences at the ends of the introns | What dictates the splice sites to generate the final mature mRNA? |
the splice sites to generate the final mature mRNA | What encodes the protein or RNA product? |
operons | What are most prokaryotic genes organized into? |
a unit | What are multiple protein coding sequences transcribed as? |
related functions | What sort of functions do the products of operon genes typically have? |
the same regulatory network | What type of network are the products of operon genes typically involved with? |
multiple protein-coding sequences | What type of coding sequences do prokaryotic genes typically have? |
enhancers | What is an example of a regulatory region of a gene that does not have to close to the coding sequence? |
because the intervening DNA can be looped out to bring the gene and its regulatory region into proximity | Why do some regulatory regions of a gene not have to be close to the coding sequence? |
a gene's introns | What part of a gene can be much larger than its exons? |
in trans | How do regulatory regions on different chromosomes operate in order to allow regions on different chromosomes to come into contact with one another? |
different chromosomes | Where can regulatory regions be found? |
the model that one gene makes one protein. | What model did early work in molecular genetics suggest? |
the discovery of genes that can encode multiple proteins | What discovery caused the model that one gene makes one protein to be refined? |
by alternative splicing and coding sequences | How do genes encode multiple proteins? |
split in short section across the genome | How are alternative splicing and coding sequences distributed? |
concatenated by trans-splicing. | In order for a gene to encode multiple proteins, how must its mRNAs be arranged? |
A broad operational definition | What sort of definition can be used to conveniently encompass the complexity of diverse phenomena? |
a union of genomic sequences encoding a coherent set of potentially overlapping functional products | What is the broad operational definition of a gene? |
their specific DNA loci | What does the typical definition of a gene categorize genes by? |
their functional products (proteins or RNA) | What does the broad operational definition of gene categorize genes by? |
regulatory elements | What does the broad operational definition of a gene classify as gene-associated regions? |
two steps are required | How many steps are required to read the information encoded in a gene's DNA and produce the specified protein? |
the gene's DNA is transcribed to messenger RNA (mRNA) | What is the first step to read the information encoded in a gene's DNA and produce the protein it specifies? |
mRNA is translated to protein | What is the second step to read the information encoded in a gene's DNA and produce the protein it specifies? |
the first step | What step must RNA-coding genes still go through? |
gene expression | What is the process of producing a biologically functional molecule of either RNA or protein called? |
The nucleotide sequence of a gene's DNA | What specifies the amino acid sequence of a protein? |
codons | What are sets of three nucleotides known as? |
a specific amino acid | What does each codon correspond to? |
a "start codon", and three "stop codons" | What indicates the beginning and end of the protein coding region? |
There are 64 possible codons (four possible nucleotides at each of three positions, hence 43 possible codons) | How many possible codons are there? |
a single-stranded RNA molecule known as messenger RNA | What does transcription produce? |
complementary to the DNA from which it was transcribed | How does the nucleotide sequence of mRNA compare to DNA? |
The gene's DNA | What is used as a template to generate a complementary mRNA? |
because it is synthesised as the complement of the template strand | Why does the mRNA match the sequence of the gene's DNA coding strand? |
an RNA polymerase | What is the enzyme called that performs transcription? |
in the cytoplasm | Where does transcription occur in prokaryotes? |
at the 5' end of the RNA | If the transcription is very long, where on the RNA may translation begin? |
transcription occurs in the nucleus | Where does transcription occur in eukaryotes? |
in the nucleus | Where does a eukaryote store the cell's DNA? |
the primary transcript | What is the RNA molecule produced by the polymerase known as? |
Translation | What is the process by which a mature mRNA molecule is used as a template for synthesizing a new protein called? |
large complexes of RNA and protein | What does a ribosome consist of? |
carrying out the chemical reactions to add new amino acids to a growing polypeptide chain | What is a ribosome responsible for? |
via interactions with specialized RNA molecules called transfer RNA (tRNA) | How is the genetic code read? |
three | How many unpaired bases does each tRNA have? |
only when the product is needed | When are genes expressed? |
available nutrients, temperature and other stresses | What are examples of a cell's external environment? |
cell division cycle, metabolism, infection status | What are examples of a cell's internal environment? |
at any step | At which step can gene expression be regulated? |
The regulation of lactose metabolism genes in E. coli | What example of post-translational modification of a protein was first described in 1961? |
A typical protein-coding gene | What is first copied into RNA as an intermediate in the manufacture of the final protein product? |
the RNA molecules | In some cases, what are the actual functional products? |
the synthesis of ribosomal RNA and transfer RNA | What sort of synthesis occurs when the RNA molecules are the actual functional products? |
enzymatic function | What sort of function are ribozymes capable of? |
non-coding RNA genes | What are the DNA sequences from which ribozymes are transcribed known as? |
in the form of RNA | In what form do some viruses store their entire genome? |
Because they use RNA to store genes | Why do the cellular hosts of some viruses not have to wait for transcription to synthesize their proteins? |
HIV | What is one type of an RNA retrovirus? |
reverse transcription | What sort of transcription does the genome of HIV require before its proteins can be synthesized? |
in plants and very rarely in animals | Besides viruses, where has RNA-mediated epigenetic inheritance been observed? |
from their parents | Where do organisms inherit their genes from? |
a complete copy | How much of an asexual organism's genome is inherited from its parents? |
two copies of each chromosome | How many copies of each chromosome does a sexual organism have? |
one complete set from each parent | How many sets of chromosomes does a sexual organism inherit from each parent? |
because they inherit one complete set from each parent | Why do sexual organisms have two copies of each chromosome? |
variations in its genotype | According to Mendelian inheritance, what is part of the cause of variations in an organism's phenotype? |
observable physical and behavioral characteristics | What sort of characteristics are described by an organism's phenotype? |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.