Cells & Genetics: Lecture 7 Flashcards
nucleus double membrane
outer: continuous with ER, ribosomes embedded in cytoplasmic side of both
inner: rests on intermediate filament scaffold (lamina)
control center of the cell
nucleus; contains all the genes and determines which proteins a particular cell will make by selectively expressing sets of genes
lamina
intermediate filament scaffold that inner membrane rests on
nuclear pores
facilitate active transport of RNA (out), proteins (in), and chemical messengers (in and out)
nucleoplasm
salts, nutrients, nucleotides, and enzymes within a nucleus; functions similarly to cytoplasm
nucleolus
ribosomal factory (rRNA)
chromatin makeup
30% DNA, 60% Histone protein, 10% RNA
-DNA wraps around cluster of 8 histone proteins to create chromosome
chromosome
2 arms of identical DNA sequence (sister chromatids)- result of DNA replication
karyotype
shows chromosomes; reveals genetic diseases
-largest to smallest, in pairs
-23rd pair: XX or XY
chromatid
arms of chromosome; joined at centromere, has a kinetochore at the centromere
centromere
point of attachment for microtubule fibers during mitosis
cellular DNA
long polymers of nucleotides connected by phosphodiester bonds
polymer partnering
each polymer associates with a partner based on specific hydrogen bonding patterns in an antiparallel orientation
-G-C
-A-T
double helix
2 strands of DNA twist around each other; most thermodynamically stable conformation; stable hereditary material
central dogma of cell biology
DNA (replication)…transcription…RNA…translation…protein
types of RNA
single stranded
mRNA, rRNA, tRNA, microRNAs
mRNA
messenger RNA; carries genetic information between nucleus and ribosomes
rRNA
ribosomal RNA; component of ribosomes, enzymatic and mRNA orientation activity
tRNA
transfer RNA; transfers specific amino acids to specific mRNA sequences during translation
microRNAs
gene regulatory and defense functions
gene
sequence of DNA that encodes for a sequence of RNA that plays a role in protein production
genome
all the DNA contained within a typical cell; spread across 23 duplicated chromosomes (46 total)
DNA replication
DNA -> DNA
transcription
DNA -> RNA
translation
RNA -> protein
triplet codons
start- AUG
stop- UAA, UAG, UGA
