Unit 2-Cell Cycle, Protein Synthesis, DNA Flashcards
codon
series of 3 bases in a strand of DNA or mRNA; codes for an amino acid
anticodon
series of 3 bases in a strand of tRNA
mitosis
process by which the nucleus of a cell is divided into two nuclei, each with the same number of chromosomes
cytokinesis
process where a cells cytoplasm is divided; happens at the end of telophase
spindle fiber
football shaped structure that aides in the movement of chromosomes
cell division
process that makes two distinct identical cells
sister chromatids
one of two distinct strands that make up a chromosome
centromere
structure that holds together pairs of chromatids
replication
DNA makes a copy of itself; happens in the S-phase of interphase
interphase
The time between cell divisions; not part of mitosis but is part of the cell cycle; divided into 3 parts- G1, S, and G2
prophase
first phase of mitosis; chromosomes become visible, nuclear membrane disappears, spindle fibers form
metaphase
2nd phase of mitosis; chromosomes line up across the equator (middle) of the cell
anaphase
3rd phase of mitosis; centromeres split and separate and move toward opposite ends of the cell
telophase
last phase of mitosis; nuclear membrane reforms, chromosomes unwind, spindle fibers dissappear
cytosine
pairs with guanine; a nitrogenous base in DNA or RNA
guanine
pairs with cytosine; a nitrogenous base in DNA or RNA
adenine
pairs with thymine in DNA and uracil in RNA
thymine
pairs with adenine in DNA (no T in RNA)
uracil
pairs with adenine in RNA (no U in RNA)
centriole
in animal cells only; aids in mitosis- organelle that produces the spindle fibers
double helix
twisted ladder shape of DNA formed by 2 separate nucleotides
nucleotide
monomer of a nucleic acid; made up of a sugar, a phosphate group and a base
DNA
deoxyribonucleic acid
mRNA
messenger RNA; copies info on a strand of DNA in the nucleus of a cell and takes it to the ribosome
tRNA
transfer RNA; copies info from mRNA in the cytoplasm near the ribosome
cell cycle
period of the beginning of one mitosis to the beginning of the next; includes interphase (G1,S,G2) and mitosis (IPMAT)
cancer
a cell that isn’t subject to normal cell cycle control mechanisms and will divide continuously
chromatin
material in chromosomes that is composed of DNA and protein (called histone); long stringy strands of DNA
base pairing
attraction between complementary nitrogenous bases
G1 (growth phase 1 of interphase)
cell grows in size and carries on day to day life sustaining activities
S (synthesis phase of interphase)
DNA replicates
G2 (growth phase 2 of interphase)
cell grows in size & prepares to divide by duplicating its organelles
point mutation
a change in a single base pair; usually only affects 1 amino acid; AKA substitution
transcription
when mRNA is made by copying info from DNA in the nucleus of a cell
intron
the portion of DNA that contains the heredity info; gets spliced out of the mRNA during transcription and stays IN the nucleus
translation
when tRNA is made by copying info from mRNA; happens in the cytoplasm near the ribosome
exon
the portion of DNA that codes for a protein; exits the nucleus on an mRNA strand
frameshift mutation
an addition or deletion of a base in DNA; every amino acid after the mutation is affected
histone
protein that DNA is wrapped around to make chromatin
protein synthesis
process of making a protein by using the instructions on DNA; 3 steps- transcription, translation, and elongation
amino acid
monomer of a protein; held together by peptide bonds
ribosome
organelle made by the nucleolus that is the site of protein synthesis
