Molecular Composition of Cells Flashcards
What does water do to support life?
Acts as universal solvent in living systems
What are Monomers ?
a molecule that can be bonded to other identical molecules to form a polymer.
What are Polymers ?
a substance which has a molecular structure built up chiefly or completely from a large number of similar units bonded together, e.g. many synthetic organic materials used as plastics and resins.
What are examples of Monomers ?
They are the building blocks of the cell
Sugars
Fatty acids
Amino acids
Nucleotides
What are examples of Polymers ?
Larger units of cells
Polysaccharide
Fats lipids, membranes
Proteins
Nuclei acid
Protein shape is critical to function, by enabling molecular recognition?
Protein shape is critical to function, by enabling molecular recognition
Protein shape is critical to function, by enabling molecular recognition?
This enzyme assists the breakdown of other proteins by hydrolysis. The red shape marks a few amino acid side chains that participate in the hydrolysis reaction. The rest of the molecule stabilises this arrangement and creates a cleft that accommodates the protein to be cleaved.
Why doesn’t oil and water not mix?
Due to the hydrophobic effect
Weakly-interacting hydrophobic molecules separate from strongly-interacting water molecules spontaneously, as this maximises entropy (Life)
What are the molecular unity of all cells ?
Solvent in all living matter: water
Structural complexity is carbon-based
Lipid bilayer membrane forms one layer of the boundary to the outside world
Nucleic acids are used to store and transmit sequence information (semi-conservative replication), including information about protein sequences
Proteins are produced by ribosomes according to this information, and carry out most functions
Many shared central metabolic pathways
ATP serves as universal energy currency
Genomes and proteomes?
How many base pairs in a single set of DNA in a cell of:
A bacterium? – E. coli: 5.4 million (single-copy genome = haploid)
A human cell? – 3.2 billion (but note 2 copies present = diploid)
This content must double just before cell division
How many amino acids, typically, in a polypeptide?
A few hundred
How many genes coding for proteins?
E. coli: 5,400
H. Sapiens: 23,000
How many proteins in a cell? – Depends on how they are counted
More than genes, due to variant proteins from the same gene, and post-translational modifications
