61 terms

DNA Test


Terms in this set (...)

What does DNA stand for?
Deoxyribonucleic acid
What is DNA's primary function?
Contains genetic information
What is the function of proteins?
They are the basic building blocks of living things and are responsible for the growth and repair of body cells and tissues
What are the repeating subunits called that make up DNA?
Name the 3 parts of a DNA nucleotides
5-carbon deoxyribose, a nitrogenous base, and a phosphate group
Name the 4 nitrogen bases on DNA
Adenine, Guanine, Thymine, Cytosine
What is the model of DNA known as? Why?
A double helix because it is composed of two nucleotides chains wrapped around each other
What makes up the sides of a DNA molecule?
Deoxyribose sugars and phosphates
What makes up the "rungs" of a DNA molecules?
Nucleotide bases
What type of bonds holds the DNA base together? Are they strong or weak bonds?
Hydrogen bonds; weak bonds
Name the complementary base pairs on DNA
A to T and C to G
How many hydrogen bonds link cytosine and guanine? Adenine and Thymine?
What is the first step that must occur in DNA replication?
Breaking of the hydrogen bonds between the two bases
What acts as the template in DNA replication?
The side opposing the new strand about to be made
What is a replication fork?
When the DNA strand is in the process of being broken up
What is the function of DNA polymerase?
Enzymes that function in the replication and repair of DNA
To which end of DNA are the new nucleotides added?
Nearest the 5 (3->5)
The strands of DNA are considered to be what to each other?
If the sequence of nucleotides on the original DNA strand was A_G_G_T_C_A, what would be the nucleotide sequence of the complementary strand of DNA?
Does replication of DNA begin at one end and proceed to the other? Explain
Why does DNA replication take place at many places on the molecule simultaneously?
It would take too long if it didn't
When replication is complete, how do the 2 new DNA molecules compare to each other and the original DNA molecule?
They are complementary
At what stage of the cell cycle is DNA replicated?
What is a mutation?
Error in the pattern of the DNA
Name several things that can cause DNA mutations
Mutations can be inherited and acquired
What sugar is found on RNA?
What base is missing on RNA, and what other base replaces it? What does it pair with?
Thymine and it's replaced with uracil, it pairs with Adenine (T is replaced with U, and it pairs with A)
Is RNA double or single stranded?
Name the 3 types of RNA and tell the shape of each
mRNA- single uncoiled chain; tRNA- single chain bent like a hair pin; rRNA
Which type of RNA copes DNA's instructions in the nucleus?
What does tRNA transport?
What 2 things make up ribosomes?
RNA and protein
Define transcription
process of creating a complementary RNA copy of a sequence of DNA
In what part of a cell are proteins made?
What is RNA polymerase and tell its function
An enzyme that catalyzes transcription
What are promoters?
DNA region where the transcription initiation takes place
Are both strands of DNA copied during transcription?
As RNA polymerase moves along the DNA template strand, what is being added?
New nucleotides
What bases pair with each other during transcription?
A to U, G to C
Which RNA molecules are involved in the synthesis (making) of a protein?
All of them
What happens to the newly made mRNA molecule following transcription in the nucleus?
mRNA molecule is being synthesized
What makes up proteins, what are subunits calls, and what bonds hold them together?
Proteins are made of amino acids; they're connected by peptide bonds
How many different kinds of amino acids make up proteins?
What determines how protein polypeptides fold into 3-dimensional structures?
By how the amino acids in the "arms" of the protein interact with water and one another
Why does a protein need a 3-dimensional structure?
When proteins fold, the 3-D structure allows different amino acids to be closer to each other
What is a codon and what does each codon code for?
Series of three bases within a reading frame of a messenger RNA
How many codons exist?
What codon starts protein synthesis?
AUG- methionine
How many amino acids does each codon code for?
One, except for the stop code
Proteins are synthesized (made) at what organelle in the cytosol?
Define translation and tell how it starts
Process where ribosomes synthesize proteins using the mature mRNA transcript produced during transcription
Where are amino acids found in a cell and how are they transported?
Found throughout the cell; transported by golgi apparatus
What is an anticodon and where is it found on tRNA?
It's a part of tRNA molecule, it has three base pair sequence
What are ribosomes made up and in what 2 places can they be found in a cell?
Made of nucleic acids and located in the cytoplasm
The start codon, AUG, pairs with what anticodon on a tRNA molecule?
What amino acid does the start codon always carry?
What type of bonds are the ones that attach amino acids to each other in a growing polypeptide?
Peptide bond
What determines the primary structure of a protein?
The amino acids called the polypeptide
What is point mutation?
When one base is substituted or changed into another case. Typically it changes from a purine to a purine, or pyrimidine to pyrimidine
What is insertion?
Mutation where a base is inserted into the DNA sequence shifting all of the other bases
What is deletion?
Mutation where the base is deleted from the DNA sequence shifting all of the other bases