Name the 6 importances of water.
It transports substances It is a reactant It is a habitat Solvent Temp control Ice is less dense
Why is water being a solvent important?
It means that some solvents dissolve in it.
Why is water being a reactant important?
Important for reactions like hydrolysis.
Why is water important for transporting substances?
Transports glucose and oxygen around animals and plants.
Why is ice important?
It is less dense than water and therefore forms an insulating layer.
Why is temperature control important?
Means it has a high specific heat capacity and high latent heat of vaporation.
Why is water being a habitat important?
Organisms survive and reproduce there.
What does hydrolysis mean?
Splitting a molecule using water.
Is the oxygen in water positive or negative?
Is the hydrogen in water positive or negative?
Why is water polar?
Because hydrogen has a positive charge and oxygen has a negative charge.
Are lots of hydrogen bonds strong or weak?
What does cohesion mean?
The attraction of water molecules to each other, caused by the polarity of the molecules forming hydrogen bonds.
What does adhesion mean?
The attraction of water molecules to different molecules caused by polarity and hydrogen bonds with other electronegative molecules.
Why is ice less dense than water?
The water molecules settle into a regular lattice shape with space between the molecules due to the hydrogen bonds.
What % of organic matter do carbs make up?
What is a polymer?
A very large molecule that is made of many small molecules called monomers.
What is a monosaccaride?
A carbohydrate whose molecules contain just one sugar molecule.
Examples of monosaccharides?
Glucose, fructose, galactose.
Are monosaccharides soluble in water?
Yes so they can easily be transported around an organism.
2 monosaccharides joined together makes what?
2alpha glucose units joined together makes what?
What happens in a condensation reaction?
A glycosidic bond is formed.
Whats the opposite of a condensation reaction?
What happens in a hydrolysis reaction?
Glycosidic bonds are broken down by enzymes.
Alpha glucose joined to fructose makes what?
Beta glucose joined to galactose makes what?
What makes a polysaccharide?
Linking together thousands of monosaccharides with a glycosidic bond.
Name a polymer.
Name the features of amylose?
Long unbranched chain of alpha glucose
Contains alpha 1-4 glycosidic bonds
Name the features of amylopectin?
Long branched chain of alpha glucose
Contains alpha 1-4 and 1-6 glycosidic bonds
Why do plants store starch?
Can be broken down easily
Doesn’t affaect water potential
Lots of branches for enzymes to attach to
Polymer of alpha glucose
Found in animal cells
Stored in liver and muscle
Similar in structure to amylopectin but has more branches.
Why is glycogen a good store carbohydrate?
Insoluble Can be broken down easily Compact Doesn't affect water potential Lots of branches
Polymer of glucose but is made up of long, unbranched chains of beta glucose.
What is the function of cellulose
Makes up plant cell walls
Explain the structure of cellulose.
Contains 1-4 glycosidic bonds
Bonds between beta sugars are straight
Is cellulose globular of fibrous?
Fibrous,strong fibres means it can provide support
Name a triglyceride.
Describe the function of triglycerides
What is an ester bond?
Carbon bound to 3 other atoms
What is cholesterol?
A lipid not made from glycerol or fatty acids.
Consists of 4carbon based rings.
Name the cations
Ca+2 Na+ K+ H+ NH4+
Name the anions
NO3- HCO3- Cl- PO4-3 OH-
What is the formula for glucose?
Features of amino acids.
Form structural components
Because they adopt specific shapes it makes them important
What elements do amino acids contain?
Carbon, hydrogen, oxygen and nitrogen.
How many amino acids are proteinogenic?
What does proteinogenic mean?
Theyare found in proteins.
What are the 3 groups of an amino acid?
What does the R mean in an amino acid?
It is no specific element.
What is a peptide bond?
Amino acids that are joined together by covalent bonds.
What are the 4 different levels of protein structure?
Function of enzymes?
Function of antibodies?
Fight disease as part of the immune system
Function of cell membranes?
Cell transport and cell recognition
Function of collagen?
Strengthens connective tissue.
Function of keratin?
Strengthens hair, skin and nails
What are the 2 groups proteins can be divided into?
Globular and fibrous
2 amino acids can join together during a condensation reaction to form what?
Steps of a biuret test for protein
Test solution should be alkaline, so add a few drops of sodium hydroxide.
Then add some coppe sulfate.
If protein is present the solution will turn purple.
No protein it will stay blue
Steps of iodine test for starch
Add iodine dissolved in potassium chloride to the sample.
If starch is present it will turn blue/black
No starch = brown/orange
Steps of emulsion test for lipids
Shake test substance with ethanol for 1 minute.
Then pour into water.
If lipid are present it will turn milky.
No lipids = stay clear
Steps of benedicts test for sugars
Add benedicts solution to a sample and heat it in a water bath that is at boiling point.
Turns green, yellow, orange or red = reducing sugar
Stays blue = no reducing sugar
After this heat a new sample with dilute HCL then neautralise sample by adding sodium hydrogen carbonate.
Stays blue = no non reducing sugar
Green , yellow, orange or red = non reducing sugar
Steps of test strips for glucose
Dip in test solution
Change in colour = glucose present
There is a colour chart for the conc of glucose
Describe the structure of haemoglobin
2 alpha glucose globin and 2 beta glucose globin chains.
Chains held together by disulphide bonds.
What does the haem group contain?
Features of insulin.
2 polypeptide chains
alpha helix and beta pleat
fold into a tertiary structure
Features of keratin.
Disulfide bridges between polypeptide bonds
Role of kertain.
Barrier to infection
Role of elastin.
Helps lungs to inflate and deflate
Role of collagen.
Provides mechanical strength
Tendonds, cartilage and tissue are made of it