bio 101 chap 12

the genetic material for life must be ___ so it can be accurately replicated over and over again.

a stable molecule.

a(n) ___ is a three nucleotide sequence in mRNA that codes for a particular amino acid.

codon

the types of nucleic acid bearing codons for the amino acid sequence is called___.

mRNA

DNA is composed of units called ___, each of which contanins a phosphate group, a 5-carbon sugar, ans one 4 nitrogen- containing bases.

nucleotide

in the 1940's, scientists had concluded that the genetic material was most likely either ___ or ____

protein or DNA

adenine and guanine are nitrogen- containing bases called...?

purine

thymine and cytosine are nitrogen- containing bases called...

pyrimidine

this nucleic acid molecule is joined with proteins and is produced in the nucleolus of a nucleus, where a portion of DNA serves as a template for its formation.

rRNA

he process of coying a DNA molecuule so that there are two copies of the same DMA is called DNA___.

replication

the characteristics that are to be expected of genetic material DNA?

stable and able to store information.

anticodons are found on which nucleic acid?

tRNA

the specific type of nucleic acid bearing anticodons for the amino acid sequwnce iss abbreviated.

tRNA

the original parent strand from which a complementary stand is made is called the ___ strand.

template

the parental strand of DNA derving as the guide for a complementary DNA daughter strand is called the ___ strand.

template

a process by which an RNA molecule is produced based on a DNA template.

transcription

indicating differences between RNA and DNA?

- DNA is double- stranded, but RNA is single-stranede - one RNA contanis the sugar "ribose" - only RNA contains the Base "uracil"

these steps in DNA replication in the correct sequence...

- unwinding the DNA double helix -complementary base pairing -joining nucleotides to the growing DNA strand.

which of the following are similarities between prokaryotic and eukaryotic DNA replication?

-both involve DNA polymerase -both happen from the 5'to 3' direction -both result in 2 copies from one parent molecule -both are semiconservaive

which of the following were direct contributions of the work of James Watson and Francis Crick?

-determined that nucleotides were paired inside the double helix -determined that sugar and phosphates formed backbones in the DNA -discovered the double helix shape of deoxyribonuleic acid

which of the following are true of transcription but not translation?

-involves RNA polymerase -occurs in eukaryotic

the characteristic of translation?

-involves tRNA molecules -results in a protein product.

which of the following are types of RNA?

-messenger RNA (mRNA) -transfer RNA (tRNA) -ribosonal RNA (rRNA)

which of the following are difference between prokaryotil and eukaryotic DNA replication?

-prokaryotes have only one origin of replication - the prokaryotic genome is replicated much faster than the eukaryotic genome

list the sequential steps of DNA replication in prokaryotes...

-the double helix is separated and unwound - DNA polymrrase binds at the origin of replication site -replication is complered at the termination region of the DNA.

a codon is composed of ___ nucleotides.

3

which choice identified the flow ofinformation according to the central dogma of molecular biology?

DNA to RNA to protein

a triplet code for amino acids is made up of ___.

RNA nucleotides

who contributed o the determination of the shape of the DNA molecule through x-ray crystallography?

Rosalind Franklin

when two molecular strands wind around each other in a double spiral, what is the structure that froms called?

a double helix

james watson and francis crick contirbuted greatly to our knowledge of the struture of the molecule know as___.

DNA

for genes that code of proteins, the mRNA sequence determines the sequence of ___ in a protein.

amino acids

when two molecular strands are connected but oriented in opposite directions, the strands are said to be ___.

antiparallel

what is the best explanation as to why the number of abenines is an organism's DNA is equal to its number of thymines?

because adenine pairs with thymine in DNA.

what is the best explanation as to why the number of guanine in an organism's DNA is equal to its number of cytosines?

because cytosine pairs with guanine in DNA

Rosalind Frankin was instrumental in the discovery that the three-dimensional shape of a DNA moleculs was a(n) ___ ___.

double helix

there are ___ different types of DAN nucleotides.

four

the mRNA transcript is read by a ribosome and converted into the sequence of amino acids in a polypeptide.

translation

the genetic code is said to be a ___ code, because a set of three nucleotids bases codes for a particular amino acid.

triplet code

true or false: a change in the DNA code will result in a change in the RNA code.

true

true or false; the DNA double helix is make up of one older strand and one newer strand.

true

true or false: a purine base normally pairs with a pyrimidine base.

true.

for the most part, every living organism on earth uses the same genetic code,therefore, the genetic code is considered ___.

universal

it is necessary for genetic material to be able to undergo mutations in order to provide genetic ___ for evolution to occur.

variation