Cells Flashcards
What are the phases of DNA replication?
Interphase, prophase, metaphase, anaphase, telophase
What is meiosis?
Germ cells divide and produce gametes. Specialised for DNA replication, produced 4 genetically different daughter cells.
What is the primary structure of a protein?
The sequence of amino acids linked by peptide bonds
What is the secondary structure of a protein?
Protein folds to form secondary structures as the amino acids have different side chains. Two regular folding patterns are seen; alpha helices (keratin) and beta pleated sheets (fibroin, silk).
What is the tertiary structure of a protein?
The 3D shape is determined by the folding of the secondary structure. A-helices and B-sheets fold to form unique structures held together by bonds.
What is the quarternary structure of a protein?
Combined three-dimensional structure of two or more polypeptide chains. e.g. haemoglobin which consists of 2 alpha and 2 beta chains.
What is a globular protein?
A protein that folds up into a compact shape.
Usually water soluble. Mobile. Chemically active. Play crucial roles in biological processes (haemoglobin)
What are fibrous proteins?
Simple, elongated 3D structures. Are insoluble in water. Provide mechanical support and tensile strength. Are abundant outside the cell. e.g. collagen, keratin, elastin
What is the “proteome”?
The proteome of a cell is all the proteins that a cell makes/
What is transcription?
DNA to RNA
What is translation?
RNA to protein
How is RNA different from DNA?
Sugar: ribose instead of deoxyribose
Strands: RNA is single-stranded, DNA is double
Chemical: RNA contains uracil, DNA contains thymine
What are the three codons that signal termination of the peptide chain?
UAG, UAA, UGA
What is post-translational modification?
The chemical modification of a protein following translation to extend its functions e.g. lipoproteins, glycoproteins.
