Chapter 4: Genetics and Cellular Function Flashcards
How many DNA molecules are in the nucleus?
46
Polymers of nucleotides
DNA & RNA
What does each nucleotide consist of?
sugar, phosphate group, nitrogenous base
double ring nitrogenous base
purines
single ring nitrogenous base
pyrimidines
purine bases
adenine and guanine
pyrimidine bases
cytosine, thymine, and uracil
Awarded for the first model of the double helix
James Watson & Francis Crick
Took x-ray photos that revealed molecular geometry of DNA
Rosiland Franklin
forms a double bond
A&T
forms a triple bond
C&G
fine filamentous DNA material complexed with proteins
chromatin
sequence of DNA nucleotides that codes for one protein
gene
2 parallel filaments of identical DNA; each=sister chromatid
chromosome
the joining point of a chromosome
centromere
protein plaque where mitotic spindle connects during cell division
kinetochore
smaller cousin of DNA (fewer bases)
RNA
carries the codes for DNA from the nucleus to the ribosomes
mRNA
temporary carriers of amino acids that carry them to put together the protein
tRNA
carries out the protein synthesis within ribosomes
rRNA
the step from DNA to mRNA; occurs in nucleus
transcription
step from mRNA to protein; mostly occurs in cytoplasm
translation
binds to DNA and assembles the RNA strand
RNA polymerase
unfinished and in immature form
pre-mRNA
nonsense removed by enzymes during splicing
intron
reconnected and exit nucleus as functional mRNA
exons
a sequence of 3 nucleotides
codon
process of removing the introns
splicing