AP Bio DNA and RNA unit

one nitrogenous base, one deoxyribose sugar, and one phosphate group

pyrimidines and purines

cytosine, thymine, and uracil

single 6-membered ring structure

adenine and guanine

double ring structure (one 5-membered ring and one 6-membered ring)

guanine

Thymine (DNA)

Uracil (RNA)

5 carbon sugar

nitrogenous base

phosphate

attached between the 5’ carbon of one nucleotide and the 3’ carbon of the next

hydrogen bonds

weak bonds are easily able to separate for copying

sugar and phosphate

antiparallel

the 3’ end of one strand faces the 5’ end of the other strand

don’t go in the same direction

double helix structure

contain a singular circular chromosome (contain one circular loop of DNA)

plasmids

linear chromosomes

DNA wraps around histone protein

nucleosomes make up chromatin fiber

coils tightly during mitosis

an enzyme which unzips the DNA at the origins of replication by breaking hydrogen bonds between base pairs

uses ATP hydrolysis

Breaks phosphate off of ATP to make ADP & release energy

enzyme that prevents strands from recoiling

prevents strands from getting tangled

requires RNA primers to initiate DNA synthesis (can only add in one direction

5’ strand adds nucleotides continuously toward the replication fork

joins fragments on the lagging strand

joins the fragments on the lagging strand

same basic process but there is a single origin of replication that proceeds in both directions

YES

each new DNA consists of one strand from the original DNA and one new strand

produces two identical copies of the DNA strand

DNA encodes RNA, RNA encodes proteins

copying or transcribing of the information in the DNA onto an mRNA

changes made to the transcribed RNA somewhat before it leaves the nucleus

how the mRNA is translated at the ribosomes to produce chains of amino acids that will be folded into proteins

messenger RNA

carries genetic info from the nucleus to the ribosomes

transfer RNA

aids in bringing the correct amino acid to the ribosome to build the proteins

ribosomal RNA

a structural component of ribosomes that is produced in the nucleolus; structural component

cell signal must first start to unwind the DNA in the nucleus at the gene that needs transcribed

one strand of DNA will be the template and RNA bases will bind to it

differs for each gene

can start with leading or lagging strand (only one will be used)

RNA polymerase unzips and rezips the DNA

promoter tells the RNA where it should start from (called the TATA box)

5’ to 3’ direction

occurs a the RNA bases are added

DNA sequence on the gene signals the termination of transcription adds the poly-A tail

5’ capping

helps protect mRNA from degradation

addition of poly-A tail at 3’ end signals it is ready to leave nucleus and go to cytoplasm

(noncoding parts of the gene) are cut out, in the trash

(expressed parts of the gene) spliced back together & mRNA leaves nucleus

codes every three bases for one amino acid

are where it all happen

bring the correct amino acids to the template

a specific amino acid

every 3 nitrogen bases

AUG

mRNA is transported to cytoplasm

attaches to a ribosome

start codon is read first

tRNA brings anti-codons

ribosome moves along the mRNA strand

read the codons of mRNA in order

tRNA brings anti-codons and donates amino acid

repeats for each codon

when the stop codon is reached translation stops

mRNA leaves the ribosome

polypeptide chain folds into 3-dimensional shape