Chapter 10 Flashcards
what is the primary function of mRNA in protein synthesis
carry genetic instructions from DNA to ribosome (messenger)
where does tRNA carry amino acids during translation
to the ribosome, where they are assembled into protein
how is an amino acid connected to the protein chain
tRNA matches its anticodon to the codon on the mRNA
what is the name of the sequence on mRNA that pairs w/ the anticodon on tRNA
codon, a 3 nucleotide sequence on the mRNA
what role does the ribosome play in translation
ensures proper alignment of mRNA and tRNA, catalyzes formation of peptide bonds between amino acids to build the protein chain
how does protein synthesis stop
when the ribosome encounters a stop codon on the mRNA
what is a stop codon
UAA, UAG, UGA, signals ribosome to release completed protein bc no more matching tRNA
what is genotype
genetic makeup of an organism, set of genes inherited from both parents
what is phenotype
physical traits or characteristics that are expressed
difference between genotype and phenotype
genotype is the blueprint while phenotype is what you actually see
diploid
two sets of chromosomes (one from each parent, like most human cells)
haploid
one set of chromosomes (gametes, like sperm)
constitutive gene
genes that are continuously expressed, help with basic functions all the time
genome
complete set of genetic material (DNA) in an organism (full collection of genetic instructions)
what is the structural difference between a eukaryotic and prokaryotic organism
eukaryotic are linear, found in nucleus, diploid (multicellular)
prokaryotic is circular and found in nucleoid (bacteria)
function of histones in DNA packaging
proteins that package and organize DNA into nucleosomes
how many chromosomes do prokaryotic cells
one haploid chromosome
DNA supercoiling
process of twisting DNA to fit compactly in the cell
topoisomerases
manage DNA supercoiling
DNA gyrase
type of topoisomerase found in prokaryotic cells, helps maintain proper structure
extrachromosomal DNA
DNA that is outside the main chromosome, not necessary for basic cellular function
plasmids
extrachromosomal DNA found in bacteria, easily transferred between bacteria for functions like antibiotic resistance
horizontal genetic transfer
genetic material is transferred between organisms (not through typical reproduction)
