The Nucleus Flashcards
main function
control structure and function of cell by protein synthesis and manufacture of enzymes.
skeletal muscle cells - many nuclei
mature RBC - none
DNA - deoxyribonucleic acid
Adenine - Thymine
Cytosine - Guanine
contains pentose sugar deoxyribose attached to a base
Complimentary base pares (AT and CG) via hydrogen bonds.
Bonds with another polynucleotide chain to form double helix.
Codon
Basic genetic code. Three nitrogenous bases for an amino acid.
Two classes of nucleic acids
deoxyribonucleic acid (DNA) ribosenucleic acid (RNA)
DNA structure
two long chains of nucleotides
Deoxyribose bonded to one of 4 bases
guanine & adenine (purines)
cytosine & thymine (pyrimadines)
Nucleotides structure (3)
a pentose (five-carbon sugar). Either ribose (RNA) or deoxyribose (DNA),
a phosphate group,
a nitrogenous base
mRNA
- can leave the nucleus and carry info to cytoplasm
Compared to DNA :
Sugar is ribose, not deoxyribose
Uracil replaces thymine
RNA is a single polynucleotide strand
which is the only molecule in the body capable of replicating itself?
DNA
what is the definition of translation?
the synthesis of a protein from a mRNA template.
what is the definition of transcription?
The process of making RNA from a DNA template.
what replaces thymine in the mRNA?
uracil
what do amino acid sequences usually start with?
AUG - methionine
what are the three phases of translation?
initiation
elongation
termination
what is the protein that wraps up DNA in the chromosome?
histone
To start transcription, where do the transcription factors dock?
transcription initiation site on the DNA strand
