Biology I- chapter 12

The blueprint of every _______ comes from the ___.

-Each protein is ultimately determined by a specific segment of DNA called a ____.

____ __________ refers to the process by which information from a gene is used in the _________ of a functional gene product.

-Products are often in the form of proteins, but can also be in the form of functional non-coding RNA (ncRNAs) molecules, such as ____ and ____.

-The __________ of genes at the molecular level affects the structure and ________ of cells, which in turn, determine the traits that an organism expresses

protein, DNA, gene, Gene expression, synthesis, rRNA, tRNA, expression, function

Two specific steps are involved in gene expression:

Transcription: the synthesis of ___ from a ___ template where the code in the DNA is converted into a RNA ____.

-Occurs in the _______

-The resultant RNA molecule is transported to the _______.

Translation: the synthesis of a _______ from a (_)RNA template where the code in the (m)RNA is converted into an amino acid sequence in a protein.

-Occurs in the _______

Known as the _______ _____ of gene expression

RNA, DNA, code, nucleus, cytosol, protein, m, cytosol, central dogma

RNA is chemically similar to DNA, except:

-It contains ______ as a sugar

-It substitutes the nitrogenous base _____ for _______

-It generally consists of a ______ strand (instead of being double-stranded).

-There are many different types of RNA molecules, each having a different function.

ribose, uracil, thymine, single

There are three main types of RNA molecules.

__________ RNA (mRNA): the product of _____________ from a protein-coding gene that “_______” the protein-building instruction

*Acts as the bridge between DNA and protein synthesis

________ RNA (tRNA): ________ amino acids to ribosomes for the process of assembling amino acids into _______.

_________ RNA (rRNA): the major component of _________ involved in the process of assembling amino acids into proteins

*_RNA and _RNA are non-coding RNA molecules; they function in the form of RNA and are __ translated into proteins.

Messenger, transcription, carries, Transfer, delivers, proteins, Ribosomal, ribosomes, r, t, not

Transcription is the process of using ___ as a template to __________ RNA.

*Gene: an organized unit of ____ sequences that enables a segment of DNA to be ___________ into RNA and ultimately results in the formation of a functional product.

Like DNA replication:

RNA nucleotides are added in the ____ direction (5’ → 3’).

RNA nucleotides are added based on ________________.

DNA, synthesize, base, transcribed, same, complementation

Unlike DNA replication, in transcription:

-Only a _____ stretch of DNA is used as the template (i.e. a ____) to synthesize RNA.

-Only ___ strand of the DNA is as the template used.

-______ (U) is put in the place of Thymine (T).

-RNA ___________(_) catalyzes nucleotide addition.

-The ________ is a single strand of RNA.

small, gene, one, Uracil, polymerases, product

Initiation: several different proteins (called transcription factors) recognize and ____ to specific nucleotide sequences in front of the gene, called the ________.

*Initiates the binding of RNA polymerase(s) to begin _____________ of the gene.

Elongation: as RNA polymerase moves along the DNA, it _______ the double helix, ______ on RNA nucleotides to the 3’ end of the growing strand of the RNA transcript.

The sequence of RNA nucleotides is determined by _______________ to the nucleotides of the gene.

*Follows the AT/GC rule, but U is used instead of T.

bind, promoter, transcription, unwinds, adding, complementation

Termination: _____________ proceeds until the RNA polymerase encounters a terminator nucleotide sequence found at the ___ of the gene in the DNA.

-The RNA polymerase falls off the DNA and ________ the newly made RNA __________.

-The RNA transcript is then processed/________ before it leaves the _______, producing the final RNA molecule.

-Modifications help protect RNA and act as __________ signals for where the molecule needs to go for translation.

-Modifications include addition of the 5’ cap and 3’ poly A tail, and splicing; removal of _________ sequences, called _______, and __________ of coding sequences, called _____.

transcription, end, releases, transcript, modified, nucleus, directional, noncoding, introns, connecting, exons

The order of nucleotides of the DNA (and subsequently mRNA) __________ the order of amino acids in a protein.

-The genetic code _________ the relationship between the nucleotides of _RNA and the ____ _____ used to build a protein.

-DNA → mRNA → Protein

The genetic code is read in groups of three nucleotides, called ______.

-The code is read ____________; the first group of _____ nucleotides _________ the first amino acid, the next group of three nucleotides specifies the second amino acid, and so forth.

-There are four nucleotides and with three consecutive nucleotides specifying a codon, this creates 4³ (64) different possible codons.

determines, specifies, m, amino acids, codons, continuously, three, specifies,

Each codon specifies which one of the __  amino acids will be incorporated (during _________) at the corresponding position in a protein.

Because each codon is comprised of _ bases, the number of nucleotides making up a ______ message must be _____ times the number of amino acids making up the _______ product.

*It would take at least 900 nucleotides to code for a protein that is 300 amino acids long.

The genetic code is __________, but specific.

More than one codon can specify the ____ amino acid.

20, translation, 3, genetic, three, protein, degenerate, same

__ of 64 codons specify an amino acid.

3 “____” codons do not specify amino acids but are signals for ___________ of the translation process.

1 “_____” codon (AUG) has a dual function and not only codes for the amino acid methionine but also acts as a ______ for the _________ of translation.

61, stop, termination, start, signal, initiation

___________ is the process of making a protein from _RNA.

All three forms of RNA introduced previously are involved in the process of translation:

-_________ RNA (mRNA).

-_________ RNA (tRNA).

-_________ RNA (rRNA).

 All forms of RNA are transcribed from specific genes in the _______.

Translation, m, Messenger, Transfer, Ribosomal, nucleus

mRNA ________ the information from the DNA (as a result of _____________).

-The nucleotide sequence of mRNA will be used for ___________ to determine the amino acid sequence of the _________ protein.

_RNA molecules attach to specific amino acids on one end of the molecule and have an “________” at the other end.

-The anticodon, is ______________ to codons in the mRNA sequence and can thus ____ pair with the mRNA ___________.

-tRNA __________ the amino acid to the ribosome/mRNA complex and when the tRNA binds with the mRNA, automatically positions the attached amino acids in the order specified by the mRNA.

provides, transcription, translation, resulting, t, anticodon, complementary, base, nucleotides, transports, 

The rRNA, in combination with various proteins, makes up a larger complex called the ________.

-The ribosome is where ___________ takes place.

-Recall from Chapter 4, ribosomes are found in three locations of the cell, the _______, the ___, and the ____________.

-The ribosome brings the appropriate _RNA molecule, takes the attached amino acid, and then joins it to the previous amino acid to form the _____.

ribosome, translation, cytosol, rER, mitochondria, t, protein

Each tRNA can be used __________:

-Picks up its designated amino acid in the _______.

-Deposits the amino acid at the ________.

-_______ to the cytosol to pick up another copy of that same amino acid.

Like that of transcription, there are many other molecules involved in the overall process of translation, including translation and regulatory factors.

repeatedly, cytosol, ribosome, Returns

The stages of translation are similar to that of what was previously discussed for transcription.

Initiation: brings together the _RNA, a tRNA with the first amino acid, and the _______ at the start codon.

Elongation: the ribosome moves along the mRNA, _________ attaching each amino acid to the previous.

Termination: occurs when one of the three stop codons is reached resulting in the _______ of the protein and translation complex.

-A ribosome requires ____ than a minute to translate an average-sized mRNA into a protein.

m, ribosome, covalently, release, less

Additional alterations may occur to the newly synthesized polypeptide to make it functional.

-Post-translational modifications included the _______ of some amino acids, or the ________ of other amino acids as well as sugars, lipids, and/or phosphates.

-Modified, packaged, and shipped to their _____ destination inside or outside the cell.

Those proteins made at the ___ will make their way through the _______________ system (Chapter 4).

Those proteins made at ribosomes in the _______ will either function within the cytosol or be transported to various organelles.

removal, addition, final, rER, endomembrane, cytosol