Nucleic acids and dna

what makes a nucleic acid

a phosphate group, a nitrogenous base, and a sugar molecule

what r group does dna have

What R group does rna have

OH

What effect does the H give dna

dna is more stable which is important for long term storage

What effect does OH give Rna

RNA is more tractive and less stable than dna, this is impoertant for its functianal roles

what are the five nitrogenous bases

denine (A), guanine (G), cytosine (C), thymine (T), and uracil (U)

what are the three pyramidine, or one ringed bases

Cytosine, Thyamine, and Uracil

What is Thymine used in and what properties does it have

DNA, it has amethyl group, and is more stable

What is Uracil used in

Rna and it is less stable

why isnt cytocisne used in dna

It can have a spotndeus deanimation into Uracil and can lead to mutations

what are the two purine bases

adedine and guanine

how are nucleotides joined

through phosphodiester bonds and a nucleotidal transfer reaction

which is stronger the bond between A-T or C-G

C-G becasue it forms three bonds instead of 2

what does protonated mean

To be protonated means a molecule has gained a proton (a positively charged hydrogen ion, H+).

what is the central dogma of molecular biology

Dna transcribed to Rna translated to protein

what kind of backbone does dna have

dna has a sugar phosphate backbone

what are the properties of the magor groove in Dna

large and info-rich; can be ”read” by proteins

without having to unwind helix

what are the properties of the minor groove in dna

smaller and more uniform; some interactions for structural stabilization and drug binding

what does antiparallel mean

that dna strands run in opposite directions

what does adenine bond with

Thymine

what does guanine bond with

cytosine

what is the width of a strand of dna

2 nm

what stabilises the double helix

hydrogen bonding and and base stacking

where does the hydrogen bonding occur

between bases across strands

base stacking is prmarily driven by

van der walls forces and hydrophobic forces (bases are very hydrophobic)

what enzyme copies dna

dna polymerase

what does semiconservative replication mean

it means replicated dna has one parent and one daughter strand

what are some major things about rna

nucleotides are linked my phosphdiester bonds

polarity is 5-3

it uses uracil instead of thiamine

it is much shorter than dna

it is single stranded but can fold in interesting patterns

what is the byproduct of a nucleotidal transfer reaction

pyro phosphate

At what sequence in DNA does RNA transcription begin?

Transcription begins at the promoter sequence

At what sequence in DNA does RNA transcription stop?

transcription stops at the termination sequence

What is the template strand of DNA?

The template strand is the strand that RNA polymerase uses to create a complimentary RNA transcript

What is the role of the nontemplate strand of DNA?

the nontemplate strand is not transcribed but its sequence matches the the transcribed RNA with the replacment of U with T

what strand of DNA is usually shown in textbooks

the template strand

Does DNA stay unzipped indefinitely during transcription?

No. Only a short section of DNA is unwound at a time. As RNA polymerase moves forward, the DNA re-anneals behind it.

What are the three main steps of transcription?

Initiation, elongation, and termination

what happens during initiation

RNA polymerase (with accessory proteins such as sigma factors in prokaryotes or
transcription factors in eukaryotes) binds to the promoter sequence. The DNA double helix is
unwound at this region, and transcription of the template strand begins

what happens during elongation

RNA polymerase moves along the template strand in the 3′ → 5′ direction, adding
complementary ribonucleotides to the 3′ end of the growing RNA transcript. The transcript is
thus synthesized in the 5′ → 3′ direction

what happens during termination

When RNA polymerase reaches a terminator sequence in the DNA, transcription
stops. The RNA transcript is released, and the DNA helix reforms.

how many types of RNA polymerase to prokaryotes have

one

How many types of RNA polymareas to eukaryotw have

Three RNA polymerases (Pol I, II, III), each for different RNA types

where do transcription and translation happen in prokaryotes

Transcription and translation are happen simultaneously in the cytoplasm

where to transcription and translation happen in Eukaryotes

Transcription occurs in the nucleus; translation in the cytoplasm (spatial separation).

mRNAs in prokaryotes ore often

polysitronic( they code for multiple protiens)

eukaryotes often have what on their promotoers

enhancers

promoter

where the rna polymerase binds to the dna

whaat is this

transcription bubble

what are protien coding genes transcribed by in eukaryotes

POL II

What does mRNA do

carries the genetic material from the DNA to the ribosome

what does the ribosome do

translates the message into protien

what direction does rna polymerase move on the template strand

3-5

what direction is the rna transcript built

5-3