DNA and RNA Flashcards
NA contains information coded in the sequence of its ____ ____. It is able to ___ ___, which is important for cell division and therefore ____.
base pairs, self replicate, reproduction
DNA Is ____ and result in the alteration of the ____ it produces, and therefore the organism’s ____. Changes in DNA are usually stable and ___ __ from generations. This provides the basis for ____
mutable, proteins, characteristics, passed down, evolution
The idea that DNA is transcribed into RNA, RNA is translated into proteins and that DNA is able to self replicate
Central dogma of molecular genetics
A nucleotide is composed of a _____ bonded to both a ___ group and a ___ ___. The phosphate and sugar form a _____ with the bases arranged as ___ __ off the chain
deoxyribose, phosphate, nitrogenous base, chain, side groups
Purine bases
Adenine, guanine
Pyrimidine bases
Cytosine, thymine
___ are larger than _____ because they possess a ____ nitrogenous base, whereas pyrimidines have ______ nitrogenous base.
purines, pyrimidines, two-ring, one-ring
If the ___ strand is at the end of the DNA strand, the end is referred to as the ____ end and likely for the ___ end.
5’ 5’, 3’
DNA are found as ___ ___ held together by ___ __ between the bases oriented towards the center.
double-stranded helices, hydrogen bonds
T forms ___ H bonds with ___, while ___ forms ___ H bonds with C.
2, A, G, 3
DNA has one strand with a ____ end pointing up and the other strand with its ___ pointing up, resulting in a _______ arrangement. This is known as the ____ ___ ___
5’, 3’ antiparallel, watson-crick DNA model
In order to replicate, the double stranded DNA helix must ___ and separate into two strands. This involves uncoiling the strands by _____, and breaking the _____ ___ between the nitrogenous bases of each nucleotide by ___ ____. The opening in the DNA molecule created is known as the ____ ____
unwind, topoisomerase, H bonds, DNA helicase, replication fork
Each single strand can act as a ____ for complementary base pairing and allows for the synthesis of two new daughter strands. Each new daughter helix contains an ____ strand from the parent helix and a ___ ____ strand. This type of replication is called _____. The daughter strands of DNA formed from the parent strand are ___ to the parent strands.
template, intact, newly synthesized, semiconservative, identical
___ _____ reads the parent DNA strand and creates a ____, ____ daughter strand This protein always reads the parent strand in the ______ direction, creating a new daughter strand in the _____ direction.
DNA polymerase, complementary, antiparallel, 3’-5’, 5’-3’
One daughter strand is the ___ _____. This leading strand is ______ synthesized by DNA polymerase, which attaches nucleotides to the exposed ___’ end of the parent strand and follows the ___ ___ to the 5’ end.
leading strand, continuously, 3’, replication fork
The other strand is called the ___ ___ and is synthesized ____ because the __ end of the parent strand is the one exposed. Therefore, DNA polymerase which can only read in the _____ direction, must continually reattach to the ______ ends of the parent strand since these ends are continuously exposed as new section of helices _____. The short fragments that result from this discontinuous synthesis are known as ___ ___, and are joined by ____ ____
lagging, discontinuously, 5’ 3’-5’ 3’ unwind, okazaki fragments, DNA ligase
In RNA the nucleosides are identical except for _____, which is replaced with ____
thymine, uracil
DNA is first transcribed into ___ and arranged into ____, also known as ____. These are then translated into ___ ___.
mRNA, triplets, codons, amino acids
There are ___ amino acids that can be formed from all possible combinations of the four nucleosides. A sequence of ___ consecutive bases codes for a particular amino acid. This genetic code is ____ for almost all organisms.
20, 3, universal
Given that ____ different codons are possible based on the ___ code and ___ possible nucleotides, and only 20 amino acids need to be coded, most amino acids have more than ___ codon coding for them. This is referred to as the ______/___ of the genetic code
64, triplet, 4, 1, degeneracy, redundancy
RNA is made up of ____, contains ___, and is usually _____
ribose, thymine, single-stranded
____ carries the complement of a DNA sequence, and it transports this complement from the ___ or the ___ for protein synthesis. mRNA is ______ meaning that one mRNA strand codes for one ______
mRNA, nucleus, ribosomes, monocistronic, polypeptide
_____ is a small RNA molecule found in the ____ which assists in the translation of mRNA’s nucleotide code into a sequence of amino acids. It brings the ___ ___ coded for in the mRNA sequence to the ribosomes during protein synthesis. tRNA has a ____ structure. One end contains a 3 nucleotide sequence called the ____ which is complementary to one of each of the mRNA codons. The other end is the site of _____ of the corresponding amino acid. Each amino acid has its own _____ _____, which has an active site that binds to both the amino acid tRNA, catalyzing their attachment to form and ______ complex. There is at least ___ type of tRNA for each amino acid, and ___ known types of tRNA
tRNA, cytoplasm, amino acid, 3D, anticodon, attachment, aminoacyl-tRNA synthase, aminoacyl-tRNA, 1, 40
_____ is a structural component of ribosomes and is the most ___ of all RNA types. The mRNA sequence passes through two ___ of the rRNA structure and is translated into amino acids at this time. rRNA is synthesized in the ____
rRNA, abundant, subunits, nucleolus
____ is the process through which information coded in the base sequence of DNA is used to direct the synthesis of a strand of ____, which then leaves the nucleus through ___ ___.
transcription, mRNA, nuclear pores
Each human chromosome is a long strand of _____ that is used to make ____ different sequences of ____. Therefore, ___ are much shorter than DNA molecules since only a segment of the original DNA strand is used as a template.
DNA, 1000, RNA, RNA
The first step of transcription occurs when ___ ____ binds to the DNA at a ___ ___, a short DNA sequence found ___ from the site where transcription of a specific RNA is going to take place. In humans this is most commonly a _____ ____
RNA polymerase, promoter region, upstream, TATA box
___ ___ then help RNA polymerase ____ to the DNA molecule and initiate transcription. RNA polymerase surrounds the DNA molecule after it has been ____ by DNA helicase and ____. The RNA polymerase then recruits and adds ____ ___ ___ based on the DNA sequence.
transcription factors, bind, opened, topoisomerase, complementary RNA nucleotides
RNA reads DNA in the ___ direction and creates a new daughter strand of RNA In the ___ direction. The RNA sequence is ___ to the original DNA sequence except that A binds with ____.
3’-5’, 5’-3’ complementary, U
RNA uses a slightly different sugar backbone than DNA< with an oxygen on ____, instead of _____
C-2, deoxyribose
After transcription is complete, RNA is known as ____ ___ or ____, and contains extra ___ that are not necessary to create the corresponding protein. These extra sequences are called ____. ____ are the nucleotides necessary to make the protein the introns are ____ out by the _____, leaving the exons behind. Additionally a ___ __ and a series of adenines known as a ____ ___ are added to the ends of the new molecule to provide protection from ___ __ once the RNA leaves the nucleus
hetero-nuclear RNA, pre-RNA, nucleotides, introns, exons, spliced, spliceosome, guanine cap, poly-a tail, enzymatic degradation
Translation occurs in the ___ and involves ___, __, ___, __ ___, ___ and other proteins. It can be divided into ___ distinct stages
cytoplasm, mRNA, tRNA, ribosomes, amino acids, enzymes, 4
___ of transcription begins when the ribosome binds to the mRNA near its ___ end. The ribosome scans the mRNA until it binds to a ___ ____, which is ____. The initiator aminoacyl-tRNA complex, ___ ____, base pairs with the start codon. This contains the anticodon _____
initiation, 5’ start codon, AUG, methionine tRNA, 3’-UAC-5’
In ____, ___ ___ form between the mRNA codon in the A site of the ribosome and its complementary ____ on the incoming ____ complex. A peptide bond is formed between the amino acid attached to the _____ in the A site and the amino acid attached to the tRNA in the ___ site of the ribosome. After, a ribosome carries ____ ___ in the p site and ____ ____ in the A site
elongation, h bonds, anticodon, aminoacyl-TRNA, tRNA, P, uncharged rTNA, peptidal-tRNA
The translation cycle is completed by ___, which the ribosome advances ____ nucleotides along the mRNA in the ___ direction. In a concurrent action, the uncharged ___ from the p site is ___ and the peptidal tRNA from the A site moves into the ___ site. The ribosome then has an empty A site ready for entry of the ______ corresponding to the next codon
translocation, 3, 5’-3’ tRNA, expelled, P, aminoacyl-TRNA
Polypeptide synthesis undergoes ___ when one of the 3 special ____ _____, ____, ___ or ____, arrives in the A site. These signals code to ____ translation, they do not code for amino acids. Frequently, numerous ribosomes simultaneously translate a ____ mRNA molecule, forming a structure known as a _____
termination, stop codons, UAA, UAG, UGA, terminate, single, polyribosome
After the release of the protein from the ribosome, the protein immediate assumes its ________ ___ ___. This is determined by the __ __ of amino acids. Additional ___ and ___ structural folding occurs based on this sequence as well. Furthermore, the polypeptide chains can form _____ and ______ _____ with ____ bonds. The result is a functional protein or complex of multiple proteins
3D native conformation, primary sequence, secondary, tertiary, intramolecular, intermolecular cross-bridges, disulfide
Ribosomes are composed of _____ subunits. one small and one large, each consisting of ___ and _____. They bind together only during __ ___.
2, rRNA, proteins, protein synthesis
Ribosomes have 3 binding sites: the _____ site, or the aminoacyl-tRNA complex binding site, the _____ site, where the tRNA is then transferred, and tRNA contributes its amino acid to the growing _____ ___, and finally the ___ site, where the tRNA is released
a, p, polypeptide chain, e
Humans and bacteria have different types of ____ that make up their ribosomes. This a difference that drug manufacturers capitalize on when designing ____. Many of these target only the ribosomal structures specific to ___ thereby leaving human cells ____
subunits, antibiotics, bacteria, unharmed