Protein Synthase Flashcards
What is the structure of RNA?
Usually single-stranded, sugar is ribose, with 4 nitrogenous bases: adenine, uracil, cytosine, guanine
RNA typically exists as a single strand, differing from DNA.
What is the structure of DNA?
Double-stranded, sugar is deoxyribose, with 4 nitrogenous bases: adenine, thymine, cytosine, guanine
DNA is double-stranded and contains thymine instead of uracil.
Where does DNA stay within a cell?
Nucleus
DNA is located in the nucleus of eukaryotic cells.
What is messenger RNA (mRNA)?
Carries instructions from the nucleus (DNA) to the ribosomes
mRNA plays a crucial role in the process of transcription.
What is ribosomal RNA (rRNA)?
Forms part of the ribosomes and bonds amino acids together through polypeptide bonds
rRNA is essential for protein synthesis.
What is transfer RNA (tRNA)?
Transfers amino acids to ribosomes
tRNA is key in translating the genetic code into proteins.
Where is mRNA produced in prokaryotes?
In the cytoplasm
Prokaryotic cells lack a defined nucleus, so transcription occurs in the cytoplasm.
Where is mRNA produced in eukaryotes?
In the nucleus and sent to the cytoplasm
Eukaryotic cells have membrane-bound organelles, including a nucleus.
Fill in the blank: The sugar component of RNA is _______.
ribose
Ribose is distinct from deoxyribose found in DNA.
True or False: DNA contains uracil as one of its nitrogenous bases.
False
DNA contains thymine, while RNA contains uracil.
Where does translation take place?
In the cytoplasm
What molecules are involved in translation?
mRNA, ribosomes, tRNA, Amino Acids
What is the sequence of events from polypeptide to functional protein?
Polypeptide → functional protein
What defines the primary structure of a protein?
The amino acid sequence
What type of structure is formed through hydrogen bonding?
Secondary structure
What is the tertiary structure of a protein characterized by?
Secondary foldings caused by interactions within the polypeptide and its immediate environment
What does the quaternary structure of a protein refer to?
The relationship between individual subunits
Fill in the blank: The amino acid sequence leads to a _______.
polypeptide
True or False: Translation occurs only in the nucleus.
False
What does DNA stand for?
Deoxyribonucleic Acid
DNA is the molecule that holds heredity.
What is the sugar component of DNA?
Deoxyribose
Deoxyribose is a pentose sugar found in DNA.
What connects sugars and phosphate in nucleotides?
Phosphodiester bond
This bond is crucial for forming the backbone of nucleic acids.
What part of a nucleotide is phosphate?
Part of a nucleotide
Phosphate is one of the three components that make up a nucleotide.
What are the nitrogenous bases found in RNA?
- Adenine
- Uracil
- Cytosine
- Guanine
RNA contains uracil instead of thymine, which is found in DNA.
What are the nitrogenous bases found in DNA?
- Adenine
- Thymine
- Cytosine
- Guanine
These bases pair specifically: A with T and C with G.
What type of structure do purines have?
6-sided ring and 5-sided ring fused together
The purines in DNA are adenine (A) and guanine (G).
What type of structure do pyrimidines have?
6-sided ring only
The pyrimidines include thymine (T) and cytosine (C).
What does 5’ refer to in DNA?
Topmost part of the strand
The 5’ end is where the phosphate group is attached.
What does 3’ refer to in DNA?
Shortest length of the strand
The 3’ end is where the hydroxyl group is attached.
What is the structure formed by the twisting of DNA?
Double Helix
This structure is essential for the stability and function of DNA.
What is a Hydrogen Bond?
Bonds the nitrogenous bases together
Hydrogen bonds are crucial for the stability of the DNA double helix.
What does ‘Antiparallel’ refer to in the context of DNA?
One strand is upside down opposite the other
This orientation is essential for the complementary base pairing.
What does mRNA stand for and what is its function?
Message RNA; carries instructions from the nucleus (DNA) to the ribosomes
mRNA is crucial for the process of translation in protein synthesis.
What is the role of Ribosomal RNA (rRNA)?
Forms part of the ribosomes and bonds amino acids together with polypeptide bonds
rRNA is a key component of ribosomes, which are the sites of protein synthesis.
What is the function of Transfer RNA (tRNA)?
Transfers amino acids to ribosomes
tRNA is essential for translating the genetic code into proteins.
What sugar is found in RNA?
Ribose
Ribose is a five-carbon sugar that distinguishes RNA from DNA.
In RNA, which base replaces thymine?
Uracil
Uracil pairs with adenine during RNA synthesis.
What is the function of RNA polymerase?
An enzyme responsible for copying a DNA sequence into an RNA sequence; binds to transcription factors in the promoter region of the gene
RNA polymerase is vital for the transcription process in gene expression.
What is the role of mRNA?
To carry protein information from the DNA in a cell’s nucleus to the cell’s cytoplasm.
What are introns?
Non-coding sections of RNA that are not included when DNA is transcribed into mRNA.
What is the function of the poly-A tail?
It is at the end of the mRNA to allow ribosomes to read the RNA before enzymes break down the mRNA.
What is mature mRNA?
Messenger mRNA that is ready to leave the ribosomes.
What are ribosomes?
Sites at which information carried in the genetic code is converted to amino acids/proteins.
What does rRNA form?
Parts of the ribosomes.
What is the role of rRNA in protein synthesis?
It bonds amino acids together to form polypeptide bonds.
Fill in the blank: The _____ carries protein information from the DNA to the cytoplasm.
mRNA
True or False: Introns are coding sections of RNA included in mRNA.
False
Fill in the blank: The _____ tail is essential for ribosome recognition of mRNA.
poly-A
What is the process called where ribosomes convert genetic code into proteins?
Translation.
What are codons?
When the mRNA code is read 3 at a time
Codons are sequences of three nucleotides in mRNA that specify a particular amino acid.
What are amino acids?
Monomers of proteins
Amino acids are organic compounds that combine to form proteins.
What are the three parts of an amino acid?
- Amino group (NH₂ or HaN)
- Carboxyl group (COOH)
- R group (unique to each amino acid)
The R group determines the specific properties of each amino acid.
What is the function of tRNA?
Transfers amino acids to ribosomes
tRNA (transfer RNA) plays a crucial role in protein synthesis.
What is an anti-codon?
Three unpaired bases on a tRNA complementary to a codon on mRNA
The anti-codon ensures that the correct amino acid is added during translation.
What is a polypeptide?
Biomaterial consisting of repeated amino acid units linked by peptide bonds
Polypeptides are chains of amino acids that fold into functional proteins.
What are peptide bonds?
An amide bond that bonds amino acids together
Peptide bonds form during a dehydration reaction between the amino group of one amino acid and the carboxyl group of another.
What is gene expression?
The process through which the information in a gene is used to synthesize a functional gene product, typically a protein.
Gene expression involves transcription and translation, leading to the manifestation of traits in an organism.
What is the simplified sequence of how genes lead to characteristics?
DNA nucleotide sequence → Amino Acids → Protein → Structure in organism.
This sequence illustrates the central dogma of molecular biology.
What does RNA stand for?
Ribonucleic Acid.
RNA plays a crucial role in coding, decoding, regulation, and expression of genes.
What sugar is used in RNA in a nucleotide?
Ribose.
Ribose is a five-carbon sugar that is a component of RNA nucleotides.
What is the polymer of RNA?
Nucleotide.
Nucleotides are the building blocks of RNA, consisting of a sugar, a phosphate group, and a nitrogenous base.
Is RNA single or double stranded?
Single.
RNA typically exists as a single strand, allowing it to fold into various shapes.
Is DNA single or double stranded?
Double.
DNA has a double helix structure formed by two strands of nucleotides.
What sugar is used in DNA?
Deoxyribose.
Deoxyribose is a five-carbon sugar that is part of the DNA nucleotide.
What base does DNA have that RNA does not, and what is the replacement?
Thymine; Uracil.
In RNA, uracil replaces thymine, which is found in DNA.
When does DNA leave the nucleus?
It does not.
DNA remains in the nucleus, while RNA is synthesized and transported out.
What leaves the nucleus instead of DNA?
RNA.
RNA carries genetic information from the nucleus to the cytoplasm for protein synthesis.