Principles Biochemistry Outcomes Flashcards
What is the mass and charge of a:
- proton
- neutron
- electron?
A proton has a mass of 1 and a +ve charge.
A neutron has a mass of 1 and no charge.
An electron has negligible mass and a -ve charge.
What happens to electrons in a covalent bond?
Electrons are shared between atoms in a covalent bond.
Describe an ionic bond.
An ionic bond occurs due to the attraction of opposite charges between ions.
Describe a hydrogen bond.
A hydrogen bond is due to the sharing of a hydrogen atom.
Define hydrophobic interaction.
Hydrophobic interaction is the interaction of nonpolar substances in the presence of polar substances (particularly water).
Define Van Der Waals interaction.
Van der Waals interaction is the interaction of electrons of nonpolar substances
Define electronegativity.
Electronegativity is the attractive force that an atomic nucleus exerts on electrons.
What are condensation and hydrolysis reactions?
Condensation reactions are the removal of water.
Hydrolysis reactions are the addition of water.
what is a redox reaction?
A redox reaction is the transfer of electrons from one molecule to another.
Differentiate between oxidation and reduction.
Oxidation is the loss of electrons.
Reduction is the gain of electrons.
Give 3 functions of biomolecules within the body.
- Information storage (DNA).
- Structure (teeth, bones, cartilage).
- Energy generation (glycolysis, citric acid cycle, electron transport chain).
- Energy currency/storage (ATP).
- Recognition/communication/specificity (receptors, hormones, enzymes)
What are the four major classes of biomolecules?
- Peptides and proteins.
2, Lipids (triglycerides, phospholipids, steroids). - Nucleic acids
- Carbohydrates.
What is an exergonic reaction?
Exergonic reactions are those in which the total free energy of the products is LESS than the total free energy of the reactants. ΔG is NEGATIVE. They may occur spontaneously.
What is an endergonic reaction?
An endergonic reaction is a reaction in which the total free energy of the products is GREATER than that of the reactants. ΔG is POSITIVE. They cannot occur spontaneously as they require an input of energy to proceed.
Account for the central role of ATP in cellular energetics
ATP is used as a universal energy currency for driving many different cellular processes.
How is ATP stored?
ATP is constantly being regenerated as cells do not store it in large amounts.
Define metabolism.
Metabolism is the sum of all of the reactions taking place in the body, and can be divided into: anabolism and catabolism.
Define catabolism.
Catabolism is the breaking down of complex molecules into smaller ones and releasing energy,
Define anabolism.
Anabolism is the synthesising of complex molecules out of smaller ones in energy consuming reactions.
Define glycolysis.
Glycolysis is a catabolic pathway, and the initial breakdown of glucose for the generation of ATP. Produces a net gain of 2 ATP molecules per glucose,
Define gluconeogenesis.
Gluconeogenesis is an anabolic pathway, and the synthesis of glucose from non-carbohydrate precursors, e.g. pyruvate. It requires energy.
What type of bonds exist between water molecules?
Hydrogen bonds exist between water molecules.
Explain the influence of water-water interactions on the organization of amphipathic molecules in an aqueous phase
When in contact with water, amphipathic molecules form micelles.
The polar head interacts well with water.
The non-polar tails do not, and are sequestered from the water.
What is meant by the term hydrophobic effect?
The hydrophobic effect is a term used to describe the behaviour of non-polar substances in water. Non-polar liquids tend to form a two-layer system with water.