Unit 6 AP Bio

linear and multiple chromosomes

dna in nucleus

single circular chromosome

free-floating

(structural) ribosomes

brings amino acids to ribosomes for protein synthesis

messenger

regulation of other genes and protein coding

1 carbon-nitrogen ring

cytosine, thymine, uracil

2 carbon-nitrogen rings

adenine, guanine

smaller circular pieces of DNA in both eukaryotes and prokaryotes

5’ to 3’ towards the fork and is continuously built

runs 5’ to 3’ away from the fork and is made in okazaki fragments

short sections of DNA formed at the time of discontinuous synthesis of the lagging strand during replication of DNA

adds nucleotides to growing strand

shows DNA polymerase where to begin building

unwinds DNA

prevents double helix from becoming too tightly wound as DNA is opened up

goes through and seals holes left by primase (closes)

bind to pieces of DNA called operators and reduces transcription

the DNA segment where the repressor molecule binds to the operon

increase transcription of the operon

cluster of genes that transcribes multiple proteins

can be turned on from off by an inducer

can be turned off from on by a core repressor

produces many copies of a target template DNA sequence (not natural)

method in which many copies of a DNA fragment of interest are made

separates DNA fragments based on their size

*shorter fragments go farther

determining the sequence of nucleotide bases in a DNA molecule

initiation, elongation, termination

nucleotides read in groups of 3 that code for amino acid sequences

the process of making RNA from DNA in order to transfer genetic information out of the nucleus and to the site of protein synthesis (the ribosomes)

COPYING

Initiation: RNA polymerase binds to a sequence of DNA at the beginning of a gene and the RNA polymerase separates the strands

Elongation: RNA polymerase reads template strand and builds an RNA molecule out of complementary nucleotides (same process as reading the template strand but T is replaced with U)

Termination: terminator sequences are coded for (STOP) and signal the completion of RNA transcript

mRNA is decoded to build a protein with a specific series of amino acids

tRNA connects mRNA codons to the amino acids they encode

• its anticodons bond to specific mRNA codons

Initiation: ribosome assembles around mRNA and is necessary to begin translation… amino acids from the tRNA are getting lined up

Elongation: amino acid chain gets longer

Termination: stop codon enters ribosome triggering events that separate chain from tRNA

the process by which instructions in the DNA are transcribed and translated into a functional protein

*the flow of information is from DNA to RNA to protein

• DNA to RNA= transcription

• RNA to protein= translation

exon:

intron:

sequences: stretches of DNA that can be used to either promote or inhibit protein synthesis

regulatory proteins are used to assist with the promotion of inhibition of protein synthesis

*the interaction of regulatory sequences with regulatory proteins controls transcription

reversible modification of DNA or histones

histones: proteins used to wrap DNA around

slight chemical modifications can cause tight packing or loose packing of DNA

*this regulates gene expression (via accessibility)

cells within the same organism having different phenotypes

proteins that promote or inhibit transcription of a gene