Science Quiz Flashcards
3 parts of a nucleotide are
Sugar, phosphate, nitrogen base
DNA is made up of monomers called
Nucleotides
The 4 nitrogen bases in DNA are
Adenine, Guanine, Cytosine, Thymine
Purines have how many bases
2 bases
Pyrimidines have how many bases
1 base
The two purines are which two nitrogen bases
Adenine and Guanine
Which two nitrogen bases are pyrimidines
Thymine and Cytosine
Based on complementary base pairing rules which bases go with which
Adenine pairs with Thymine
Guanine pairs with Cytosine
A purine always pairs with what
A pyrimidine
DNA nucleotides always link together by what reaction
Condensation reaction
The sugar of nucleotide is linked to the what of the next nucleotide and the covalent bond formed is called a what bond
Phosphate
Phosphodiester bond
In a phosphodiester bond a molecule of water is
Released
A DNA molecule contains how many strands of nucleotides and these nucleotides are held together by what type of weak bond
Hydrogen
The shape of the DNA is
A double helix
The sides of the double helix are repeating what
Sugar and phosphate groups
The sequence of bases in the chain will determine what
Characteristics of an organism
RNA is made of monomers called
Nucleotides
The 3 parts of the nucleotide are the same except what
The sugar is ribose instead of deoxyribose
The RNA bases are what
Adenine, Guanine, Uracil, and Cytosine
Uracil basically takes the place of what
Thymine
RNA forms a chain but what is different about the chain
The chain is single stranded instead of double stranded
DNA holds the
Genetic information
What does RNA help DNA do
Make proteins
What phase does DNA replication occur
S phase of interphase
DNA is semi- conservative, what does this mean
- No DNA molecule is ever completely new
2. There is always one original strand and one new strand
Proteins are made up of what
Amino acids
Amino acids are connected by a covalent bond called a
Peptide bond
A what reaction occurs to link to amino acids together
A condensation reaction
A condensation reaction releases what
A water molecule
There are how many different amino acids
20
mRNA, messenger RNA, does what
Copies code from DNA in nucleus and takes it to ribosome in cytoplasm
tRNA, Transfer RNA, do what
- Bring an amino acid to the ribosome
- Has a cloverleaf shape
- Anticodon on bottom pairs with codon in mRNA
rRNA, Ribosomal RNA, are what
Is what the ribosome is made of- with some proteins too
Small sections of DNA that code for proteins are called what
Genes
Genes contain bases in how many groups and are called what
3
Triplets
The order of bases in a gene determine what
The order of amino acids in a protein
How does the code for DNA that is in the nucleus and proteins at are made in the cytoplasm move
mRNA
What happens during Transcription, and where does this happen
The code for DNA is copied onto mRNA and it happens in the nucleus
What happens during Translation
The code on mRNA is carried to the ribosome for the amino acid to become a protein
A gene in DNA is unzipped by what enzyme to form two strands
RNA polymerase
Free what move into place along one DNA strand
RNA nucleotides
What enzyme assembles these nucleotides and what does it use
The enzyme is RNA polymerase and it uses complementary base pairing
The molecule of mRNA moves out to go to the ribosome and what enzyme zips it back up
RNA polymerase
Any triplet in mRNA is a codon except what
The very last triplet, UAA
How many combinations of triple based pairs are there
64
Translation involves all 3 types of RNA, what are they
mRNA, tRNA, rRNA
a tRNA molecule with a what complimentary to a mRNA start codon carries over the first amino acid of any polypeptide chain
Anticodon
What bond is formed between the tRNA anticodon and the mRNA codon
Hydrogen bond
The first tRNA molecule detaches from the what
Ribosome
The ribosome keeps moving along, one codon at a time until it reaches the what
Stop codon
Stop codons only do what
Tell the ribosome when to stop translation
The polypeptide chain does what from the ribosome and takes on its function in the cell
Dismantles
