Chapter 7 DNA structure & gene function Flashcards
What is DNA made up of?
(DNA is a double helix made up of nucleotides.)
Phosphate group, sugar (deoxyribose) and a nitrogenous base (adenine, thymine, guanine, and cytosine.)
What is DNAs function?
DNA stores the information that a cell needs to produce proteins.
Which nitrogenous bases are double ring structures and which are single ring? And what are those called?
Adenine and guanine are double ring (purines)
Thymine and cytosine are single ring (pyrimidine)
What type of bonds Connect complementary DNA strands?
Hydrogen bonds
What are the complementary base pairing’s?
Adenine binds to thymine
Guanine binds to cytosine
What is genome?
All of the genetic material in it cells
What are chromosomes?
Long DNA molecules that associate closely with proteins
What is a Gene?
Sequence of DNA nucleotides that code for specific protein or RNA molecule (blueprint)
What is the central dogma of biology?
DNA to RNA (transcription) to protein (translation)
What are the two stages of protein production?
Transcription and translation
What are the three types of RNA? And their functions?
mRNA-carries the info that specifies a
Protein
rRNA-forms part of a ribosome in the nucleolus
tRNA-connector that binds mRNA codon at one end and corresponding amino acid at the other. Transfers amino acids available one by one to ribosome.
What is the complementary RNA bases to DNA?
Adenine to Uracil
Cytosine to guanine
Guanine to cytosine
Thymine to adenine
Where does transcription occur?
In the nucleus
What are the three stages of transcription?
Initiation, elongation, and termination.
What happens in initiation for transcription?
RNA polymerase binds to the promoter, enzymes unzip the DNA, the DNA template strand encodes the RNA molecule.
What happens in elongation of transcription?
RNA polymerase moves along template strand making an RNA copy. RNA molecule is complementary to the DNA template strand.
What happens in termination for transcription?
RNA polymerase reaches the terminator, RNA DNA and RNA polymerase separate, DNA becomes a double helix again.
What happens with Intron’s and exons?
Intron’s are spliced out of the RNA molecule before exiting the nucleus. Exons are spliced together and exit the nucleus for translation.
What occurs after termination in transcription, before the mRNA exits the nucleus?
Poly A tail and mRNA CAP Are added to the mRNA. Intron’s are spliced out.
What are the three steps of translation?
Initiation elongation and termination.
What result occurs in translation as an end result?
The construction of a protein