Proteins and Nucleic Acids Flashcards

Flashcards from lecture notes on Proteins and Nucleic Acids.

What is the role of enzymes?

Speed up reactions (catalyze).

What is the defensive biological role of proteins?

Antibodies that recognize foreign substances.

What is the role of receptors in proteins?

To receive and respond to signals.

What is the storage role of proteins?

To store amino acids for later use.

Give an example of a structural protein.

Collagen.

Give an example of a transport protein.

Hemoglobin.

Which proteins are involved in movement?

Contraction and motor proteins.

What are the building blocks of proteins?

Amino acids.

How are amino acids grouped by their side chains?

Nonpolar, polar, and electrically charged.

Where do nonpolar side chains tend to be located within a protein?

Cluster together on the inside of the protein.

What type of bonds do polar side chains form?

Form hydrogen bonds.

What type of bonds do electrically charged side chains form?

Forms ionic bonds.

What are peptide linkages?

Covalent bonds that link amino acids together.

What is a polypeptide's primary structure?

Specific and unique sequence of amino acids linked covalently between N & C termini.

What type of bonds are involved in secondary structure?

Hydrogen bonds form between the amino and carboxyl groups of the amino acid building blocks forming α-helices and β-pleated sheets.

What bonds and interactions occur in tertiary structure?

Ionic / hydrogen bonds, hydrophilic/phobic interactions, van der Waals interactions, disulfide bridges.

What is quaternary structure?

Interactions of side chains of 2 or more different polypeptides bound together using all interactions/ bonds giving a fibrous or globular shape

What are chaperonins?

Protein molecules that assist in the proper folding of other polypeptides.

What happens when a polypeptide is denatured?

Breaks down the bonds and interactions that hold the secondary & tertiary structure together.

What are the biological uses of nucleic acids?

Storage, transmission, and use of genetic information.

What are the storage and transmission roles of nucleic acids?

DNA is a permanent storage place, and RNA transmits the genetic information from DNA to the protein synthesizers in the cell.

What is chromatin?

DNA wrapped around protein.

What are the building blocks of nucleic acids?

Nucleotides.

What are the three steps of genetic information transmission and use?

DNA Replication, Transcription, Translation.

What happens during DNA replication?

DNA makes identical copies of itself for every cell.

What happens during transcription?

DNA's genetic information is transmitted into an RNA copy.

What happens during translation?

RNA uses the genetic information transcribed from DNA to create a new protein (polypeptide).

What is the structure of nucleotides?

Monomers of nucleic acids made up of a nitrogenous base, a pentose sugar, and a phosphate group.

What are the nitrogenous bases in DNA and RNA?

Adenine (A), Guanine (G), Cytosine (C), and Thymine (T); in RNA, Thymine is replaced by Uracil (U).

What are the base pairing rules in DNA?

A pairs with T (or U in RNA); C pairs with G.

What is gene expression?

The process by which the information encoded in DNA is used to synthesize functional products, such as proteins.

What is a gene?

A sequence of DNA that codes for a specific protein or RNA molecule.

What is a genome?

The complete set of genetic material in an organism or cell.

What is genomics?

The study of whole sets of genes and their interactions.

What is DNA?

Double stranded nucleic acid that contains the genetic instructions for all known living organisms.

What is RNA?

Single stranded nucleic acid that performs various functions including regulation and expression of genes.

What is mRNA?

Messenger RNA: Encodes amino acid sequence of a polypeptide.

What is tRNA?

Transfer RNA: Brings amino acids to ribosomes during translation.

What is rRNA?

Ribosomal RNA: With ribosomal proteins, makes up the ribosomes, the organelles that translate the mRNA.

What is snRNA?

Small nuclear RNA: Participates in RNA splicing, helps to regulate gene expression.