biomolecules Flashcards
What elements make up carbohydrates, lipids, proteins?
All: C, H, O (carbon, hydrogen, oxygen)
Protein (extra, in addition to CHO): N, S (nitrogen, sulfur)
State 2 things that are synthesized from glucose.
Glycogen and starch
State 1 thing synthesized from amino acids.
Polypeptides
State 1 thing synthesized from fatty acids and glycerol.
Lipids (e.g. fats)
What is the structure of starch?
A mixture of 2 polysaccharides (amylose and amylopectin), consisting of glucose molecules
What is the role of starch?
Major storage carbohydrate of most plants as an important energy source
Starch is a _____ (soluble / insoluble?). It is built from many ____ molecules condensed together.
Starch is a polysaccharide (insoluble). It is built from many monosaccharide molecules condensed together.
What is the structure of a triglyceride?
3 fatty acid molecules + 1 glycerol molecule
How are triglycerides formed?
Formed by condensation reactions (removal of water) between fatty acids and glycerol
What are the bonds formed in triglycerides called?
Ester bonds
Triglycerides are ____ molecules, but ___ when compared to glycogen and starch. Because of their ___, ___ properties, triglyceride molecules clump together into huge ___ (appear as macromolecules).
Triglycerides are large molecules, but small when compared to glycogen and starch. Because of their non-polar, hydrophobic properties, triglyceride molecules clump together into huge globules (appear as macromolecules).
What are the 2 types of triglycerides and what distinguishes them?
Saturated triglycerides: No double bonds in fatty acid tails (solid)
Unsaturated triglycerides: One or more double bonds present in fatty acid tails (kinks/bends, cannot be compacted –> liquid)
What is the difference in structure between phospholipids and triglycerides?
Phospholipids have a similar chemical structure to triglycerides except one of the fatty acids is replaced by a phosphate group
Is the phosphate group hydrophilic or hydrophobic?
The phosphate group is ionised and therefore water-soluble (hydrophilic).
What are the 4 structures of proteins?
Primary structure, secondary structure, tertiary structure, quaternary structure
The ____ structure of a protein is the long chain of ____ ____.
The primary structure of a protein is the long chain of amino acids.
The ____ structure of a protein develops when either part or all of the ___ chain becomes ___ to produce an a-helix or it becomes ___ to b-sheets.
The secondary structure of a protein develops when either part or all of the polypeptide chain becomes coiled to produce an a-helix or it becomes folded to b-sheets.
The ___ structure is the precise, compact structure, ___ to the protein that arises when the molecule is further folded and held in a particular ___ shape.
The tertiary structure is the precise, compact structure, unique to the protein that arises when the molecule is further folded and held in a particular complex shape.
The ___ structure of a protein arises when 2 or more polypeptides become ___ ____, forming a complex, biologically active molecule.
The quaternary structure of a protein arises when 2 or more polypeptides become held together, forming a complex, biologically active molecule.
What is denaturation? When does denaturation occur?
Denaturation is the loss of the three-dimensional structure of a protein. It happens when the bonds that maintain the 3D shape of the protein are changed.
Name 2 factors that change/disrupt bonds.
Exposure to heat disrupts hydrogen and ionic bonds, pH changes alter ionic bonds. (enzymes! structure determines function)
Name 4 properties of water.
- Has high specific heat capacity (much thermal energy required to raise water temperature)
- High latent heat of vapourisation (allows cooling by evaporation)
- Universal solvent in biological systems, a key component of tissues
- Water molecules are highly cohesive (xylem vessels)
