BIO 11W Unit 2
Put the following events of translational elongation (the stage in translation that occurs after initiation) in the order that they occur, beginning with the first steps at the top. -The ribosome releases the first tRNA. -After the first amino acid has been brought to the ribosome, a tRNA carrying the second amino acid of a protein binds to the second codon. -The ribosome releases the second tRNA. -A covalent bond forms between the first and second amino acids. -The ribosome moves down the mRNA by one codon, and a tRNA carrying the third amino acid comes into place. -A covalent bond forms between the second and third amino acids.
1. After the first amino acid has been brought to the ribosome, a tRNA carrying the second amino acid of a protein binds to the second codon. 2. A covalent bond forms between the first and second amino acids. 3. The ribosome releases the first tRNA. 4. The ribosome moves down the mRNA by one codon, and a tRNA carrying the third amino acid comes into place. 5. A covalent bond forms between the second and third amino acids. 6. The ribosome releases the second tRNA.
Select all the statements about nucleotides that are accurate. 1. DNA always contains the same sugar in its nucleotides 2. RNA contains the sugar deoxyribose in its nucleotides 3. They are composed of a sugar, a nitrogen-containing group, and one or more phosphorus-containing groups. 4. They are the building blocks of proteins.
1. DNA always contains the same sugar in its nucleotides 3. They are composed of a sugar, a nitrogen-containing group, and one or more phosphorus-containing groups.
Select all of the following that can be components of RNA nucleotides. 1. phosphate 2. thymine 3. deoxyribose 4. ribose 5. adenine 6. uracil
1. phosphate 4. ribose 5. adenine 6. uracil
Select all the statements about nucleotides that are accurate. 1. RNA contains the sugar deoxyribose in its nucleotides. 2. They are composed of a sugar, a nitrogen-containing group, and one or more phosphorus-containing groups. 3. DNA always contains the same sugar in its nucleotides. 4. They are the building blocks of proteins.
2. They are composed of a sugar, a nitrogen-containing group, and one or more phosphorus-containing groups. 3. DNA always contains the same sugar in its nucleotides. *Not 4. Amino acids are the building blocks of proteins
Select all of the following that describe RNA. 1. always occurs as a double-stranded helix 2. nucleotides contain the sugar ribose 3. the nitrogenous base thymine is used instead of guanine 4. can catalyze chemical reactions 5. can be single-stranded 6. nucleotides contain the sugar deoxyribose 7. the nitrogenous base uracil is used instead of thymine
2. nucleotides contain the sugar ribose 4. can catalyze chemical reactions 5. can be single-stranded 7. the nitrogenous base uracil is used instead of thymine
______ are portions of mRNA that get sliced together to form mature mRNA before translation occurs in eukaryotes.
Exons
During transcription, what reads the template strand within a gene and adds complementary bases?
RNA polymerase
gene
a sequence of nucleotides that codes for a specific protein or RNA molecule
Two strands of DNA within the double helix are said to be complementary to each other because ________ on one string always pairs with thymine on the opposite strand, and cytosine on one strand always pairs with ________ on the opposite strand.
adenine; guanine
On a tRNA molecule, the _______ is a three-base sequence that is complementary to and binds to an mRNA codon during translation.
anticodon
What three-base site of a tRNA molecule is complementary to an mRNA codon?
anticodon
nucleotide
building block of nucleic acids
In an RNA molecule, a _______ is a genetic "code word" that corresponds to one amino acid.
codon
During transcription, a gene's DNA sequence is transcribed into a
complementary RNA molecule
During the elongation phase of translation, a ______ bond is formed between the incoming ______ acid and the growing polypeptide chain, and empty tRNAs are released from the ribosome to be reused.
covalent; amino *a peptide bond is a type of covalent bond
chromosome
discrete package of DNA coiled around proteins
What are coding regions of eukaryotic mRNA that are translated?
exons
True or false: Complementary base pairing rules state that in DNA, A pairs with G and T pairs with C.
false
A(n) _____ is a sequence of DNA nucleotides that that codes for a specific protein or RNA molecule.
gene
In the 1960s, researchers deciphered the ________, which determines what amino acid is specified by each three-nucleotide _________.
genetic code; mRNA codon
All of the genetic material that is within a cell is called its
genome
DNA molecule
includes many genes
A(n) ________ is a portion of mRNA that is about 1,000 nucleotides long and that is removed before translation.
intron
In archaea and eukaryotes, a part of an mRNA molecule that is removed before translation is called a(n)
intron
Because ribosomes cannot "read" a gene directly, the genetic information to make a protein is "transcribed" into a(n) ________ molecule, which in turn is "translated" by the ribosome to make a __________ molecule.
mRNA; protein
The flow of information from _______ acids in DNA to _______ is sometimes called the "central dogma."
nucleic; proteins
A single strand of DNA consists of a polymer of ______ monomers.
nucleotide
Subunits called _____ are the building blocks of nucleic acids, as determined by scientists by about 1930.
nucleotides
RNA _______ is the enzyme that builds the RNA chain during transcription.
polymerase
The ______ is a sequence of DNA that signals the start of a gene and is the site where RNA polymerase binds to begin translation.
promoter
A ______ ribosome is composed of rRNA and proteins and is the site of protein synthesis.
ribosome
What structure is the site of protein synthesis / translation?
ribosome
In a process called ______, an RNA copy of a gene sequence on the DNA molecule is made.
transcription
In the "central dogma" describing the flow of genetic information from DNA to protein, DNA is copied to RNA in a process called ______, and the information in RNA is used to direct the synthesis of a protein in a process called _______.
transcription; translation
In a process called _______, an RNA molecule is used to produce a protein.
translation
