DNA
What makes the beginning of a new gene on DNA in eukaryotes?
AUG (start codon)
What are promoters?
The promoter region is the region of the DNA where the enzymes to create mRNA would attach and begin reading it
What is the function of proteins?
To make 3D structures and to communicate through chemical interactions
What is the error rate in DNA replication? What helps lower this error rate?
enzymes that proofread or "repair enzymes" lower the rates
What is the difference between a purine and a pyrimidine?
Different chemical shapes- why it can't bind with the same type
Where are amino acids found and how are they transported?
Found in the cytoplasm transported by tRNA
Who is responsible for determining the structure of the DNA molecule and in what year was this done?
Francis Crick and James Watson in 1953 determined the structure of the DNA molecule
Difference between proteins made by cytoplasmic ribosomes and ER ribosomes?
Free ribosome created proteins don't need as much packaging and process to become functional
How many hydrogen bonds link cytosine and guanine? adenine and thymine?
Guanine and cytosine have 3 bonds while adenine and thymine have 2 bonds
Name the four nitrogen bases on DNA
Guanine, Cytosine, Adenine, and Thymine
What enzymes help separate the 2 strands of nucleotides on DNA? What bonds do they break?
Helicase and polymerase break the hydrogen bonds
What base is missing in RNA and what other base replaces it?
In RNA, thymine is replaced by uracil.
How does the nucleotide sequence in one chain of DNA compare with the other chain of DNA?
It has complimentary base pairs
When a promoter binds to DNA, what happens to the double helix?
It opens up
How did Rosalind Franklin contribute to determining the structure of DNA?
Rosalind Franklin developed the first x-ray image of DNA and therefore was able to determine the basic dimensions of a DNA molecule
What is the genetic code and why is it important?
Set of instructions on how to make an organism
What determines how protein polypeptides fold into 3 dimensional structures?
The chemical interactions of the individual amino acids
Translation
The process of translating a sequence of messenger RNA to a sequence of amino acids during protein synthesis. starts when the ribosome attaches to the mRNA
Where does RNA polymerase bind to the DNA its transcribing?
The promoter region
What do promoters mark the beginning of on prokaryotic DNA?
The starting point of opening the circular DNA
What acts as the template in DNA replication?
The template strand
Why does DNA replication take place at many places on the molecule simultaneously?
There is a lot of different proteins that have to get made all at once.
When replication is complete, how do the 2 new DNA molecules compare to each other and the original DNA molecule?
They each have one original strand of DNA
Define transcription.
Transcription is the process in which one strand of DNA is copied and turned into a complimentary strand of RNA
What type of bonds holds the DNA bases together? Strong or weak?
Weak Hydrogen bonds-holds together because there are a lot
Can more than one ribosome at a time translate an mRNA transcript?
Yes multiple can attach because the mRNA doesn't dissolve until there are no ribosomes translating it
Name several things that can cause muatations
change in the structure of a chromosome: deletions duplications, inversions, and translocations.
The model of DNA is known as a _______ because it is composed of two _______ ______ chains wrapped around each other
double helix, complimentary nucleotide
Which type of RNA copies DNA's instructions in the nucleus?
mRNA
Name the 3 types of RNA
mRNA, tRNA, rRNA
On DNA, a _____ base will always pair with a _______ base.
purine, pyrimidine
Which type of RNA is most abundant?
rRNA
What 2 things make up ribosomes?
rRNA and protein
What are ribosomes made of and where are they found?
rRNA, cytoplasm and endoplasmic reticulum
Proteins are synthesized at what organelle in the cytoplasm?
ribosome
In what part of a cell are proteins made?
ribosomes
Name the complimentary base pairs on DNA.
Adenine and thymine, Guanine and Cytosine
What sugar is found in DNA?
Deoxyribose
Name 3 parts of a DNA nucleotide
Deoxyribose sugar, phosphate group, and the base
How many base pairs are in a full twist of a DNA molecule?
10 base pairs in each twist
How many binding sites are found on the ribosomes and what does each site hold?
2 binding sites, holds a point for the mRNA to attach
How many different kinds of amino acids make up proteins?
20 different kinds of amino acids
How many codons exist?
64 codons exist
What is a mutation?
A mutation is a mistake in the coding of DNA
What is a replication fork?
A set of enzymes unzip the DNA and copy the strands at the same time
Uracil will pair with what other on DNA?
Adenine
Name two purines
Adenine and Guanine
What makes up the "backbone" of the DNA molecule?
Alternating sugar and phosphate groups
What makes up the sides of a DNA molecule?
Alternating sugar and phosphate groups
What does tRNA transport?
Amino acids
Is DNA replicated before or after cell division?
Before, because in order for cells to divide, DNA must be replicated
Why must DNA be able to make copies of itself?
Cell division-needs another set of DNA to be able to make mRNA (a cheap copy) to send out of the nucleus in protein synthesis.
What is an anticodon and where is it found on tRNA?
Complimentary codon that matches up with a codon on mRNA- on the end of tRNA
Does replication of DNA begin at one end and proceed to the other?
Could begin anywhere on the strand of DNA and then it moves in one direction
Name two pyrimidines
Cytosine and Thymine
What is the first step that must occur in DNA replication?
DNA has to unwind before it separates
What is the function of DNA polymerases?
DNA polymerase builds new segments to pair with the separated strands of DNA
Define DNA replication
DNA replication: semi conservative replication
What is DNA's primary function?
DNA's function is to provide the instructions for life
What does DNA stand for?
Deoxyribonucleic acid
What makes up the "steps" of a DNA molecule?
Nitrogen bases
Are both strands of DNA copied during transcription?
No, only one
What is the most common form of DNA found in organisms?
Nuclear DNA
What are the repeating subunits called that make up DNA?
Nucleotides
_______ are joined to replicating strands of DNA by ______ bonds
Nucleotides, Hydrogen
What makes up proteins, what are the subunits called, and what bonds them together?
Polypeptide, amino acids, peptide bonds
Is RNA double or single stranded?
RNA is single stranded
What is RNA polymerase and tell its function
RNA polymerase: when the DNA is being read the RNA polymerase creates the strand of mRNA