Science DNA + RNA

replication

replication

The copying of DNA

semiconservative

each double helix has one old and one new strand of nucleotides

during the s phase of interphase

when does replication occur

so after cell division each new cell has a copy of the DNA

why replicate dna

one point; 2

replication begins at ______ in prokaryotes and proceeds in __ directions

hundreds of points; 2

in eukaryotes replication occurs at ______ and proceeds in __ directions

replication fork

site of separation and replication

unwind and unzip the double helix

1st step of dna replication

add new nucleotides

second step of dna replication

bond together to super phosphate backbone

third step of dna replication

helicase

the enzyme that unwinds and unzips the dna strands at the replication fork exposing the nitrogenous bases

dna polymerase

enzyme that binds free nucleotides floating in the nucleus with the newly exposed nitrogen bases

5 to 3

dna builds from the __________ direction

3 to 5

dna is read _________

okazaki fragments

the fragments in dna segments that are produced by discontinuous synthesis

ligase

enzyme that binds nucleotides together forming new strands of dna (super glue)

chromatin

a combination of dna and proteins is called

codes for genetic information

function of nucleic acids

yes

are nucleic acids organic

genes

dna is made of ______ (small section of dna)

genome

all genetic info (DNA) in organism

chromosomes, chromatic, dna, genes, proteins, traits

copy/say this: chromosomes, chromatic, dna, genes, proteins, traits

nucleotides

the monomer of nucleic acids

sugar, phosphate, nitrogen base

three ingredients to a nucleotide

deoxyribosenucleic acid

dna stands for….

deoxyribose

what sugar is in dna?

adenine; guanine; cytosine; thymine

the four bases types of nitrogen bases in DNA

double helix

shape of dna

phosphates and sugars

back bone of dna

nitrogen bases

rungs of dna

h-bonds

what type of bond holds the nitrogen bases together in the center (the two strands of dna)

covalent

in dna sugars and phosphates are joined by ______ bonds

anti-parallel

dna is a____-p______; the two sides never cross or touch

3 prime

the side of dna that ends with no phosphate

5 prime

the side of dna that ends with a phosphate

3 prime to 5 prime

dna is read from ______ to _____

chargaff’s rule

the rule that states dna has an equal ration of A’s to T’s and C’s to G’s and that a goes with t and g goes with c

thymine

adenine pairs with

cytosine

guanine pairs with

ribonucleic acids

what is rna (what do the letters mean)

ribose

what sugar is in rna

adenine; guanine; cytosine; uracil

nitrogen bases of rna

single helix

shape of rna

messenger rna

the rna that brings instruction from the dna in the nucleus to the ribosomes in the cytoplasm

ribosomal rna

the rna that binds to the rna and uses the instructions to assemble the amino acids in the correct order to make the right protein (site of protein synthesis)

transfer rna

the rna that delivers amino acids to the ribisome to be assembled into proteins

single stranded

shape of mrna

single stranded loop of rna (upside down T)

shape of t rna

changes so it is clearly rna and no confusion

why is there uracil in rna and not dna

transcription

copying part of a DNA base sequence (gene) into an mRNA nucleotide sequence

interphase

when does rna happen

in the nucleus of the cell

where does transcription take place

so the genetic info can leave the nucleus and go to the ribisome

why does transcription happen

1. enzyme helicase binds to dna and zips apart the dna

2. using one dna strand as a template enzymes copy the dna base sequence

3. at the end of the gene transcription stops and the mrna molecules is released

4. DNA strand rewinds into double helix

steps of transcription

translation

the process of changing mRNA sequence into Amino Acid chains and linking together amino acids to make proteins

amino acids

monomers of proteins

ribosomes

where does protein synthesis/translation occur at

codon

3 bases in mRNA

the p site

where the tRNA first comes in contact with the mRNA complemant

the a site

where the amino acid from a tRNA is attached to another amino acid in a growing chain protein

the e site

the exit site where tRNA who have given up their amino acids to the protein leave the ribosomes

aug

what is the starting codon

una

uag

uga

what is the stop codon