Module 2.1.2 - biological molecules Flashcards
What is an ion?
An atom or molecule in which the total number of electrons is not equal to the number of protons
What is a molecule?
When 2 or more atoms bond
All living things are made up from what 4 elements?
carbon, hydrogen, nitrogen, oxygen
What is the bond rule?
Carbon - 4
Nitrogen - 3
Oxygen - 2
Hydrogen - 1
What is a covalent bond?
When 2 atoms share a pair of electrons
What is Ca 2+ needed for?
Nerve impulse transmission and muscle contraction
What is Na+ needed for?
Nerve impulse transmission and kidney function
What is K+ needed for?
Nerve impulse transmission and stomach opening
What is H+ needed for?
Catalysis transmission and pH Determination
What is NH4+ needed for?
Production of nitrate ion by bacteria
What are biological molecules made up of?
Polymers which are long chain molecules with multiple linked monomers
What is OH- needed for?
Catalysis of reactions and pH determination
What is PO4 3- needed for?
Cell membrane formation, nuclei acid, ATD formation and bone formation
What is Cl- needed for?
Balance of positive charge of sodium and potassium ions
What is HCO3- needed for?
Maintenance of blood pH
What is NO3- needed for?
Nitrogen supply to plants for amino acids and protein formation
What does polar mean?
has areas of positivity and negativity
What always has a greater share of electrons compared to hydrogen?
Oxygen
An atom with a greater share of electrons will be?
Slightly more negative
An atom with a smaller share of electrons will be?
Slightly more positive
Why does water have a high boiling point?
The hydrogen bonds between the molecules take a lot of energy to break
What does water become when it turns into ice?
Less dense
Why is ice less dense?
Hydrogen bonds fix their positions of the polar molecule slightly further apart
What does cohesive mean?
Moves as one mass because molecules are attracted to each other
What does adhesive mean?
Water molecules are attracted to other molecules
What does water act as?
- a solvent
- a medium for chemical reactions
- transports dissolved compounds in and out of cells
- a coolant
What is the surface tension of water strong enough to hold?
Small insects
Why does water provide a constant temperature environment?
It doesn’t change temperature or become a gas easily
What is the formulae for glucose?
C6H12O6
What type of monosaccharide is glucose?
Hexose monosaccharide as has 6 carbons
What type of molecule is glucose?
Polar molecule
Why is glucose soluble in water?
Hydrogen bonds that form between the hydroxyl groups and water molecules
What is the formulae of ribose?
C5H10O5
What type of monosaccharide is ribose?
Pentose monosaccharide as has 5 carbons
What is the most important pentose present in living organisms?
Ribose
What is ribose’s functional group?
Aldehydic as it’s an aldose sugar
What is the formulae for starch?
(C6H10O5)n
What is starch?
A polysaccharide made up of 1,4 linkages between glucose molecules
What is starch made up of?
Long chains of sugar molecules that are connected together
What is the most basic form of starch?
The linear polymer amylose (amylopectin is the branched form)
What is the formulae for glycogen?
C24 H4 O21
What is the main energy store in animals?
Glycogen
What is glycogen formed from?
Many molecules of alpha glucose joined together by 1,4 and 1,6 glycosidic bonds
What do the side branches of glycogen do?
Means energy can be release quickly as enzymes can act simultaneously on these branches
On a molecular diagram, which way do you number the carbons?
Clockwise, starting to the right of oxygen
What does Benedicts solution test for?
reducing sugars or non-reducing sugars
What are the results of the Benedicts test?
+ brick red colour
- blue colour
What happens to non-reducing sugars when combining with Benedicts solution?
They don’t react so the solution stays blue
What is the most common non-reducing sugar?
Sucrose
What does adding HCL to a non-reducing sugar do?
Is hydrolysed by the acid to glucose and fructose, both are reducing sugars
What is used to test for starch?
Iodine
What are the results of using iodine to test for starch?
+ yellow/brown turns to purple/black
- stays yellow/brown
What are reagent strips used for?
Test for the presence of reducing sugars (glucose)
How can the concentration of the sugar be determined when using a reagent strip?
Colour-coded chart
What are carbohydrates made of?
Carbon, hydrogen and oxygen
What are monosaccharides?
Monomers that make up carbohydrates
What are the monomers that make up carbohydrates called?
Monosaccharides
What are monosaccharides joined together by?
Glycosidic bonds
What is a disaccharide?
When 2 monosaccharides join together
What is a polysaccharide?
When more than 2 monosaccharides join together
What is the main energy store in plants?
Starch
How do plant cells get energy?
From glucose and excess glucose is stored as starch
Why is starch good for storage?
It is insoluble so doesn’t cause water to enter via osmosis
What is starch a mixture of?
A mixture of 2 polysaccharides of alpha glucose : amylose and amylopectin
What is amylose?
A long unbranched chain of alpha glucose