Chapter 1 - Biological Molecules Flashcards
What are polymers
Long molecules made up of many smaller molecules
What are monomers
Small molecules that make up polymers
What is the polymer of carbohydrates
Polysaccharide
What is the monomer of carbohydrates
Monosaccharides (eg glucose)
What is the polymer of proteins
Polypeptide chain/protein
What is the monomer of a protein
Amino acids
What is the monomer of fats/lipids
Triglycerides
What is the polymer of nucleic acids
DNA/RNA
What is the monomer of nucleic acids
Nucleotides
What is a condensation reaction
When 2 molecules join together to form one larger molecule and one molecule of water
What is a glycosidic bond
A bond between molecules in carbohydrates
How is a glycosidic bond formed
Through a condensation reaction
What is a hydrolysis reaction
When molecules are split apart using a molecule of water
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What is a disaccharide
A molecule made up of 2 monosaccharides
What is the disaccharide maltose made up of
Glucose + Glucose
What is the disaccharide sucrose made up of
Glucose + Fructose
What is the disaccharide lactose made up of
Glucose + Galactose
What is the formula for glucose
C6H12O6
What are the 2 forms of glucose
Alpha
Beta
What does alpha glucose look like
H at the top
What does beta glucose look like
H at the bottom
What is a polysaccharide
Many monosaccharides joined together
What reaction occurs to join monosaccharides together to form polysaccharide
Condensation reactions
What are 3 examples of polymers of carbohydrates
Cellulose
Starch
Glycogen
Where is cellulose found
Plant cell walls
What is cellulose made from
Beta glucose
What bonds are found in cellulose
Glycosidic Bonds
How can the structure of cellulose be described
- Unbranched/straight chain
- Has more strength (to hold cells and protect)
- Insoluble (no effect on water potential so no effect on osmosis)
What are the 2 types of starch
Amylose
Amylopectin
Where are both amylose and amylopectin found
In plants, for energy storage (glucose), and for respiration
What are both types of starch made from
Alpha glucose
What bonds are found in both amylose and amylopectin
Glycosidic bonds
What are amylose and amylopectin
Types of polymers of starch
How can the structure of amylose be described
- Unbranched and coiled (to compact storage of glucose)
- Insoluble (doesn’t effect water potential so no effect in osmosis)
What is cellulose made from
Beta glucose
What bonds are found in cellulose
Glycosidic Bonds
Where are both amylose and amylopectin found
In plants, for energy storage (glucose), and for respiration
How can the structure of amylopectin be described
- Branched (increase surface area, so can be hydrolysed more quickly)
- Insoluble, so no effect on water potential and no osmosis
Where is glycogen found
In animals, for glucose/energy storage
What is glycogen made from
Alpha glucose
What bonds are found in glycogen
Glycosidic bonds
How can the structure of glycogen be described
- Branched (more than amylopectin) so Increase surface area for faster hydrolysis
- Insoluble so no effect on water potential or osmosis
What is the test for starch
1) Add iodine to sample
2) Turns blue/black if present, stays orange if negative
What is the test for carbohydrates
Benedicts test
What can the benedicts test be used for
Carbohydrates, both reducing sugars and non-reducing sugars
What is the benedicts test for reducing sugars
1) Add benedicts solution
2) Heat in water bath to 100c
3) Turns red if present, blue if not
What do you do if benedicts test for reducing sugars remains blue
Test for non reducing sugars
1) Add hydrochloric acid
2) Heat in water bath to 100c
3) repeat test for reducing sugar
4) If red, non-reducing sugar is present
If blue, there are no carbs/sugar present
What is the monomer of lipids/fats
Triglycerides
What are triglycerides made up of
Glycerol and fatty acids
Draw glycerol next with 3 fatty acids
3.1.3
Draw a triglyceride
Glycerol and 3 fatty acids joined
3 water molecules off of it
What are the characteristics of a saturated fatty acid
Don’t have double bonds between carbon atoms
What do saturated fatty acids cause
An increases in cholesterol and low density lipoproteins
What are the characteristics of unsaturated fatty acids
Have double bonds between carbon atoms, causing a kink in its chain
What do unsaturated fatty acids have less of
Hydrogen atoms, because of their double bonds between carbons
What 3 elements do lipids contain
Carbon
Hydrogen
Oxygen
What bonds are in lipids
Water bonds
What does saturated/unsaturated triglyceride refers to
The fatty acids on it, whether they have double bonds between carbons or not
What is the function of a triglyceride
Store of energy
How can the structure of triglycerides be explained
- Long polymers with many bonds
- Insoluble, so no effect on wp or osmosis
What do triglycerides form inside cells
Fat droplets
Draw and label a fat droplet
Looks like jelly fish in a circle
Hydrophilic heads point outwards
Draw a phospholipid
Glycerol in middle
Phosphate group (hydrophilic head) in left
2 fatty acids, bonded by water bonds, on the right
What is the function of phospholipids
- Form cell membranes
- Control what goes in and out of a cell
What is a phospholipid bilayer
When a cell membrane consists of 2 layers of phospholipids, tails are always pointing inwards
Why are the tails of phospholipids always pointing inwards in a phospholipid bilayer
To make the middle hydrophobic so that it is difficult for polar molecules eg water to diffuser through
What is the test for lipids called
The emulsion test
What is the emulsion test
1) Mix substance with ethanol
2) Add water
3) If positive there will be a cloudy white layer
What is a protein
A polymer of amino acids
What is essential to a proteins function
It’s shape
What are amino acids
The monomers that make up proteins
Draw an amino acid
On left: N with 2 H’s
Middle : R group at top, C, H
On right: COOH, C bonded to O and OH
What is a dipeptide
2 amino acids that are joined by a peptide bond
How do a dipeptide form
2 amino acids bonds through a condensation reaction (water molecule released)
Draw a dipeptide being formed
C double bonds to O
Bonded to N which is bonded to H
How to remember the types of proteins
EATS
What does EATS stand for (proteins)
Enzymes
Antibodies
Transport
Structural
What is the test for proteins
Biuret test
What is the biuret test
1) Add biuret reagent/solution (blue)
2) If present, will be purple/lilac
If not, stays blue
How do you describe a primary structure protein
A sequence of amino acids
What bonds are in a primary structure protein
Peptide
How do you describe a secondary structure protein
Long chains of amino acids that fold into regions with repeating patterns
What bonds are in a secondary structure protein
Peptide
Hydrogen
How do you describe a tertiary structure protein
The final 3D testing shape of the protein
What bonds are in a tertiary structure protein
- Peptide bonds
- Hydrogen bonds
- Ionic bonds
- Disulphide bridges
What do disulphide bridges do
Connect 2 different regions
How do you describe a quaternary structure protein
Proteins made up from more than one polypeptide chain
Example of a protein with a quaternary structure
Haemoglobin
What bonds are in a quaternary structure protein
- Peptide
- Hydrogen
- Ionic
- Disulphide
How to structure an answer to a question about the shape of a protein and how it performs its function
- Tertiary structure of protein
- Means active site is
- Complementary in shape to substrate
- So enzyme-substrate complex forms
What are 2 ways that a protein may be non-functional
Mutation
Denatured
How does a mutation or denaturing cause a protein to be non-functional
- Changes tertiary structure
- Changes shape of active site
- Substrate is not complementary
- Enzyme-substrate complex can’t form
What is meant by denaturing
A permanent change to the shape of the active site of a protein
Meaning enzyme-substrate complex’s can’t form
What is an enzyme catalyse reaction
A reaction that’s activation energy falls as it is catalysed
What are 5 factors affecting the rate of enzyme catalysed
- temperature
- pH
- Enzyme concentration
- Substrate concentration
- Inhibitions (competitive and non-competitive)
How does an increase in temperature (to optimum) effect reactions
- Increase collisions
- Higher % of collisions have activation energy
- More enzyme-substrate complexes can form
How does an increase in temperature after its optimum effect reactions
- Bonds break as molecules vibrate
- Active site shape changes
- Can’t form enzyme-substrate complex’s
What effect does an increase or decrease from the optimum pH of the reaction have
Causes enzyme activity (rate of reaction) to fall
Why does the rate of reaction fall if the pH is not at its optimum
- Hydroxyl (alkaline) or hydrogen (acidic) ions will interact with hydrogen or Ionic bonds
- Changes shape of tertiary structure
- Change shape of active site
- fewer enzyme-substrate complex’s
- Enzyme denatured
How does enzyme concentration effect the rate of reaction
- Increase causes increase (positive correlation)
- More possibility for enzyme-substrate complex’s to form
How may an increase in enzyme concentration not increase the rate of reaction
- Substrates May be running out
- Therefore they will be the limiting factor
How does substrate concentration effect the rate of reaction
- Increase as it increases
- More possible collisions
- More enzyme-substrate complex’s
How may an increase in substrate concentration cause no change in rate of reaction
- All active sites may become occupied
- Enzyme concentration becomes limiting factor
What do competitive inhibitors do
Bind to active site of enzyme, so enzyme-substrate complex’s can’t be formed
What will an increase in competitive inhibitors do to effect the rate of reaction
- Bing to active sites of proteins
- Deny Enzyme-Substrate complex’s
What do non-competitive inhibitors do
- Bind to Enzyme not at the active site
- Distort shape of active site
How will an increase in non-competitive inhibitors effect the rate of reaction
- Decrease opportunity for enzyme-substrate complex’s
