DNA/RNA mrs. smith honbio test

Attaches the RNA primer at the beginning of DNA synthesis

DNA primase

DNA polymerase attaches to what at the beginning of DNA synthesis

Replication fork

What occurs in the S phases of the cell cycle?

DNA replication

what enzyme connects places of DNA

DNA ligase

a and g

purines

c t u

pyrimidine

dna made up of

nucleotides

nucleotides comprised of

5 carbon sugar (dna=deoxyribose)

phosphate group

nitrogenous base

what carry the genetic information in genes that are necessary to assemble all of the macromolecules of the body?

Nucleic acids

chargaff rules=

base pairing

base paring

amount of a=t

g=c

*all end in “ine”

who used x-ray diffraction

rosalind franklin

photo 51

x-ray pattern that helps show the structure of Dna

who built first model of dna

watson and crick

the 2 strands in dna are

anti parallel

where can dna be found in prokaryotic cells

cytoplasm(w/ 1 dna molecule usually)

where can dna be found in eukaryotic cells

in the cell nucleus in the form of chromosomes (number of chromosomes vary from species to species)

dna replication being a semi conservative process means

in each new strand of dna half is new and half is old

how many base pairs in a few hours

10 bil

dna rep in prokaryotes

single point and continues in 2 directions

dna rep in eukaryotes

hundreds of places continues in both directions till completion

sites where speration and replication occur

replication forks

dna helicase

unzips dna molecule to carry of dna rep

what r broken between base pairs as two strands of DNA unwind

hydrogen bonds

3’ to 5’

leading strand

5’ to 3’

lagging strand

nucleotides can only be added to what end

the 3’

dna pol in antiparallel elongation

copies backward to the growing strand in the 5’ to 3’ in small okazaki fragments

rep continues until

dna pol reaches a primer

what happens when primer falls off

patched with some dna

okazaki fragments are joined by what as dna polymerase detaches

dna ligase

single strand binding protein

stabilize the dna strand that has been unwound until it is replaced

telomeres

areas of dna located at the end of chromosomes may protect somatic cells for cancer contain 100 to 1000 repeating units TTAGGG on the ends of chromosomes to protect them get shorter, which each replication associated with the aging process

rna contains

coded info for making proteins

genes are

Coded DNA instructions that controlled the production of proteins

difference between rna and dna

sugar in RNA is ribose instead of deoxyribose. RNA is single stranded. RNA contains uracil in place of thymine.

mRNA

Carries genetic messages from DNA to the ribosome for the synthesis of proteins

Set of three mRNA bases

codon

ribosomal rna

made of DNA that resides in the nucleolus make up ribosomes

tRNA

transfers, each amino acid to the ribosome has a site for amino acid one side antico on the other

each set of Transfer RNA three bases is

An anticodon the complementary sequence to mRNA codon

first step in creating protein

Transcription

transcription

DNA is copied into mRNA using an enzyme called RNA polymerase. The process begins at a section of DNA called the promoter.

TATAA box

directions to tell them molecule where to begin transcription

pre mRNA

what transcription process makes

pre mrna gets

modified

non coding regions that do not prouce a protein

intron(cutout)

coding region that produces protein

exon(spliced together)

how mandy codons for 20 amino acids

64

aug

start( if begining) or met(if middle)

stop codons

UAA UAG UGA

translation

decoding of an mRNA message into a peptide chain (protein)

where does translation take place

ribosomes

protein is built as what brings amino acids to the ribosome holding the mRNA?

tRNA

how many different versions of TRNA are in the cytoplasm at all times

20

most mutations are

neutral

what types of mutations are inheritable

if they are in gametes

point mutation

occurs at a single point in the DNA sequence

silent point mutation

Substitution that leads the same amino acid

missense point mutaion

One piece is changed to another usually affect no more than one amino acid

nonsense point mutation

Changes amino acid to stop codon is a substitution

friendship mutation

Shift entire reading frame of gentic code

examples of frameshift mutation

Insertion adding a random letter to the sequence at any point

Deletion getting rid of a letter at any point in sequence

chromosomal mutations

Changes in the number of structure of chromosomes can change the location of genes of chromosomes or the number of copies of genes

deletion (chromosomal mutation)

loss of all or part of a chromosome

duplication (chromosomal mutation)

produces extra copies of parts of a chromosome /polyploidy/ (down syndrom)

inversion

(chromosomal mutation) parts of chromosomes are flipped

translocation

when a piece of one chromosome breaks off attaches to a different chromosome (chromosomal mutation)

mutagens

physical and chemical agents that cause a change in DNA

teratogen

leading to birth defects of the fetus

operons

group of genes that work together

operator

switch in operons located in promoter region tell s it where to start

repressor

bound to operator. and switched it off blocks rna pol

inducer

inactivates repressor

hox gene

Group of genes that determine your body plant mutations here can be detrimental

histone modifications

acetylation(-COOH3) makes the chromatin space out and promotes transcription

DNA methylation

additional if a methyl group(-CH3) to DNA mostly cytosine inactivates DNA