unit 1.1

Chemical elements are joined together to form biological compounds

inorganic ion definition

a molecule/ ion that has no more than one carbon atom

organic ion definition

molecules that has more than 1 carbon atom

what concentration of macro nutrients is needed

small

what concentration of micro nutrients is needed

trace

magnesium (mg²⁺) use in plants + mammals

plants- required to make chlorophyll
mammals- contributes to bone strength

iron (fe²⁺) use in humans

component of haemoglobin 

phosphate (PO₄³⁻) uses

• making nucleotides (e.g ATP)

  • component of phospholipids found in membranes

calcium (ca²⁺) uses in plants + mammals

plants- component of plant walls

mammals- important structural component of bones + teeth

hydrogen bonds form between

a partial positive and a partial negative charge

explanation of water’s high specific heat capacity

large amount of energy needed to raise it’s temp (prevents big fluctuations) keeps aqueous habitats stable

roles of water as a metabolite (reactant + product)

• reactant in photosynthesis + hydrolysis 

• product of aerobic respiration + condensation reaction

metabolite definition 

substance made or used during the chemical reactions inside a cell

explanation of water’s high latent heat of vaporisation

lot of energy needed to change from liquid to vapor (important in temp control in body e.g sweat)

explanation of water’s high density

expands as it freezes + denser than air provides support + buoyancy

monosaccharide formula 

Cn​H2n​On​

what is a monosaccharide 

one unit of sugar

what is a disaccharide

two units of sugar

what is a polysaccharide

many units of sugar

two monosaccharides create a disaccharide in what reaction?

condensation reaction

isomer definition 

same chemical formula but different chemical structure

what bond are monosaccharides joined by

1,4 glycosidic bond

What 2 monosaccharides make maltose

Glucose + glucose

What 2 monosaccharides make lactose

Glucose + glactose

What 2 monosaccharides make sucrose

Glucose + fructose

What is a condensation reaction

bond formed between two molecules involving the removal of a water molecule

What is a hydrolysis reaction

When water is added to a reaction to separate two molecules

Difference between alpha and beta glucose

attached to carbon 1- In alpha H is at the top and in beta H is at the bottom

What is starch made from

Amylose + amylopectin

Starch properties

• no osmotic effect

• Compact

• Carries lots of energy

Amylose structure

Spiral and long unbranched chains

Amylopectin structure and why

Highly branched due to 1,4 AND 1,6 glycosidic bonds

What type of glucose is amylose and amylopectin made of

Alpha glucose

Storage molecule in humans

Glycogen

Storage molecule in plants

Starch

Glycogen stored as

Granules in cytoplasm

What bonds does glycogen have

1,4 AND 1,6 glycosidic bonds

Is cellulose used in animals or plants

Plants

Cellulose structure

Parallel chains with hydrogen bonds creating microfibrils

What glucose is cellulose made of

Beta glucose

Glucose units in cellulose are…

Inverted to their neighbor exposing carbon and oxygen

What are microfibrils formed from

Cross linked chains

Chitin properties

• strong

• Waterproof

• Lightweight

Where is chitin used

Exoskeleton of insects

How is Chitin structure similar and different to cellulose

Sim- beta glucose + creates microfibrils

Diff- amino acid group added

Lipids are made of

Glycerol + fatty acids

Differences between lipids and carbohydrates

• lipids have less oxygen

• Lipids are insoluble in water

Triglycerides are made of

1 glycerol + 3 fatty acids

When a triglyceride is made in a condensation reaction how many water molecules are removed

3

What bonds are formed in a triglyceride

Esther bonds

Esther bond definition

When a hydroxyl group from the glycerol bonds with a carboxyl group of the fatty acid

Phospholipid structure

Phosphate head + two fatty acid tails

Properties of phosphate head in phospholipids

• polar

• Contains oxygen

• Soluble in water

• Hydrophilic

properties of fatty acid tails in phospholipids

• doesn’t contain oxygen

• Non polar

• Hydrophobic

Waxes use in mammals + plants

Waterproof

M- exoskeleton

P- leaf cuticle

What are saturated fatty acids

Carbons bonded to max amount of hydrogen

Saturated fatty acids state at room temp + why

Solid- no kinks in chain so can join together uniformly

Unsaturated fatty acids definition

Has double carbon-carbon bonds so max bonds with hydrogen aren’t reached

Unsaturated fatty acids state at room temp + why

Liquid- kinks in chain due to double bonds meaning it can’t join together uniformly

Mono-unsaturated definition

One carbon-carbon bond

Poly-unsaturated definition

More than one carbon-carbon double bonds

Phospholipids main uses

• electrical insulator

• Biological membranes

Triglycerides main uses

• energy reserves

• Protect internal organs

• Thermal insulation

Triose example

Glyceraldehyde

Pentose examples

Ribose + deoxyribose

Hexose examples

Alpha + beta glucose + fructose + galactose

how does a high intake of saturated fat contribute to heart disease?

it raises low- density lipoprotein (LDL) cholesterol

what is the effect of raised LDL cholesterol?

increases the incidence of atheromas in coronary arteries

4 basic components of a protein structure

• amino group

• Carboxyl group

• Hydrogen atom

• Variable R group

Amino acid @ ph7…

Gains H so is positively charged

Carboxyl @ ph7…

Loses H so negatively charged

What reaction creates a protein

Condensation reaction

How a dipeptide is drawn changes the…

Properties

Bond in a protein chain

Peptide bond

Protein primary structure

Order of amino acids in the polypeptide chain

Protein secondary structure

Twists into 3d shape held together by hydrogen bonds forming alpha helix or beta pleated sheet

Protein tertiary structure

3d shape (secondary folded) b variable k group determines bonds created

Possible bonds formed at tertiary structure

• hydrogen bonds

• Ionic bonds

• Disulphide bonds

• Hydrophobic interactions

Fiborous protein is a…

Structural molecule

Fibrous protein properties

• parallel chains with many cross linkages

• Strong and tough (triple helix)

• Stable (linked by hydrogen bonds)

Globular proteins properties

• compact

• Not stable (easily denatured)

• Most have a metabolic role

Why globular proteins are folded into spherical molecules

So that hydrophilic groups are on outside and hydrophobic on inside

Test for protein

• few biuret reagent drops

• Reacts to make copper hydroxide that reacts with peptide bonds

• Turns purple

Test for fats and oils

• add absolute ethanol (dissolves any lipids)

• Shake with equal volume water

• Dissolved lipids form emulsion

• Turns cloudy white

Test for reducing sugars

• add Benedicts

• Heat 70-90

• Colour turns blue- brick red

Starch test

• add potassium iodide

• Turns black/ blue

Test for non reducing sugars

• add Benedicts heats turns blue

• Add hydrochloric acid + sodium hydroxide

• Heat

• Turns brick red

Limitation of all food tests

Qualitive test so don’t have accurate measurement