Back to AI Flashcard MakerBiology /OCR Biology A - 2.1.2 - Biological Molecules Part 4
OCR Biology A - 2.1.2 - Biological Molecules Part 4
This deck covers key concepts about biological molecules, including the chemical elements that make up lipids, proteins, and nucleic acids, as well as the properties and functions of water, and tests for various biological substances.
What are the chemical elements that make up lipids
Carbon Hydrogen Oxygen
Tap or swipe ↕ to flip
Swipe ←→Navigate
1/25
Key Terms
Term
Definition
What are the chemical elements that make up lipids
Carbon Hydrogen Oxygen
What are the chemical elements that make up proteins
Carbon Hydrogen Oxygen Nitrogen Sulfur
What are the chemical elements that make up nucleic acids
Carbon Hydrogen Oxygen Nitrogen Phosphorous
What type of links are formed in the synthesis of lipids
Ester links are formed by condensation between the alcohol groups on a glycerol molecule and three fatty acids
What happens as a result of water’s polarity
Adjacent water molecules are attracted to and become bonded to each other
How are hydrogen bonds formed
The slight positive charge of a hydrogen atom of one molecule is attached to the slight negative charge of an adjacent oxygen atom
Related Flashcard Decks
Study Tips
- Press F to enter focus mode for distraction-free studying
- Review cards regularly to improve retention
- Try to recall the answer before flipping the card
- Share this deck with friends to study together
| Term | Definition |
|---|---|
What are the chemical elements that make up lipids | Carbon Hydrogen Oxygen |
What are the chemical elements that make up proteins | Carbon Hydrogen Oxygen Nitrogen Sulfur |
What are the chemical elements that make up nucleic acids | Carbon Hydrogen Oxygen Nitrogen Phosphorous |
What type of links are formed in the synthesis of lipids | Ester links are formed by condensation between the alcohol groups on a glycerol molecule and three fatty acids |
What happens as a result of water’s polarity | Adjacent water molecules are attracted to and become bonded to each other |
How are hydrogen bonds formed | The slight positive charge of a hydrogen atom of one molecule is attached to the slight negative charge of an adjacent oxygen atom |
Functions of water | Transport Chemical reactions (metabolism) Temperature control - high latent heat of evaporation (stable environment for aquatic org.) Support Efficient transport medium - cohesion and adhesion Reproduction |
Transport as a function of water | Transpiration stream and water-based movement of sugars and amino acids, hormones etc. in phloem occurs in solution Many essential metabolites dissolve completely |
What is the transpiration stream held together by | Cohesion | Adhesion |
Cohesion | Water molecules hydrogen bond to other molecules |
Adhesion | Water molecules bind to the side of xylem vessel |
Chemical reactions as a function of water | Combination of thermal stability and excellent solvent properties make water and ideal environment for chemical reactions Water acts as a reactant for: 1) . Light dependent stage in photosynthesis 2) . Hydrolytic reactions |
Support as a function of water | In plant cells water offers turgidity In animals, water-filled tissues also contribute to skeletal support For aquatic organisms, water provided support through buoyancy |
Reproduction as a function of water | Water brings the male and female gametes together in fertilisation Foetus develops in water filled sac |
Test for starch | Iodine dissolved in KI turns from brown/orange to blue/black |
Test for reducing sugars (all mono, maltose and lactose) | Benedict’s test Add Bendicts reagent Heat solution in water bath > 80 degrees for 5 mins Solution turns from blue to green/ yellow/ orange/ brown or brick-red suspension |
Test for proteins | Biurets test Add NaOH Add copper (II) sulphate solution Solution turns from blue to purple if protein's present |
Test for lipids | Emulsion test Add water and shake Add ethanol to dissolve lipid A white emulsion/ band floating near or at the top in the presence of lipids |
Properties of water influenced by its polar nature | Solvent properties Thermal properties Cohesion tension Specific heat capacity |
Types of lipids | Triglycerides Phospholipids Saturated and unsaturated fatty acid |
What chemical elements make up lipids | Carbon Hydrogen Oxygen |
Components of a triglyceride | 1 glycerol molecule and 3 fatty acid chains attached by Ester bonds |
What are triglycerides known as | True fats or neutral fats |
Characteristics of triglycerides | Rich in energy and used to store energy Good insulators and provide buoyancy Can be broken down in aerobic respiration and water is released |
Saturated fats | Solid at room temp Only single bonds Have a lot of hydrogen Found in animals Higher melting point |