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Biology Mrs Mander > Biological Molecules > Flashcards

Flashcards in Biological Molecules Deck (28)
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1
Q

What is a Macromolecule?

A

A very large molecule created by the polymerisation of smaller subunits (monomers)

2
Q

Features of a Carbohydrate

A
o Polysaccharide
o Used to store and supply energy
o Contains C, H and O
o General formula: Cx(H20)x
o Stored as glycogen in humans and starch in plants
3
Q

Features of a Protein

A

o Used for transport and structure
o Basic components of all enzymes, hormones, antibodies, haemoglobin, ribosomes etc
o Subunits - amino acids

4
Q

Features of a Lipid

A

o Part of the cell membrane
o Provide insulation and protection
o Act as minor energy supply
o Subunits - Fatty acids and glycerol

5
Q

Roles of Carbon

A

o Forms the basis of organic life
o Can form large structures via covalent bonding
o C, H, O, N, P, S are the most abundant molecules

6
Q

What is Metabolism?

A

The totality of chemical processes that occur within a living organism in order to maintain life.

7
Q

What happens in Hydrolytic reactions?

A

o Water molecule used
o Covalent bond is broken
o Smaller molecules are formed by the splitting of a large molecule

8
Q

What happens in Condensation reactions?

A

o Water molecule released
o New covalent bond formed
o Smaller molecules formed by splitting of a larger molecule

9
Q

Properties of Water

A
o 'Sticky'
o Polar (contains H bonds)
o Universal solvent
o Cohesive
o High SHC and latent heat of vaporisation
o Transparent
o More dense than ice (insulate)
o High surface tension
10
Q

Features of a Monosaccharide

A

o Simplest carbohydrates as a single monomer, building blocks
o Formula - (CH20)n (n can be 3, 5 or 6; carbon backbone)
- n=3 (triose)
- n=5 (pentose)
- n=6 (hexose)

11
Q

Features of a Glucose molecule

A

o 6 carbons - hexose
o Polar and soluble molecules due to the H bonds between hydroxyl groups and water molecules
o Can be transported easily as its a monosaccharide
o Have lots of bonds for strength/support
o Can form polysaccharides for storage

12
Q

Alpha Glucose vs Beta Glucose

A

o Alpha - The OH group of C1 is pointing in the opposite direction to the CH20H (down)
o When 2 are joined together chemically to form a polymer, starch is formed
o Beta - The OH group of C1 is pointing in the same direction as the CH20H (up)
o When 2 are joined together chemically to form a polymer, cellulose is formed

13
Q

What is an Isomer?

A

A compound with the same molecular formula but a different arrangement of atoms
- Alpha and Beta glucose are isomers of each other

14
Q

Features of Pentose

A

o Contain 5 carbon atoms; long enough to form rings
o Ribose and Deoxyribose (DNA and RNA)
o Difference is ribose has one H atom and -OH group attached to C2 whereas deoxyribose has 2 H atoms and no -OH group

15
Q

Features of a Disaccharide

A

o Formed form 2 monosaccharides through a condensation reaction
o Forms glycosidic bonds
o Used for transport
E.g. maltose, lactose and sucrose

16
Q

Features of Polysaccharides

A

o Monosaccharides linked by glycosidic bonds
o Formed by condensation reactions
o Energy store and structural component of cells
E.g. Cellulose, starch and glycogen

17
Q

What are the 2 polysaccharides of Starch?

A

Amylose and Amylopectin

18
Q

Features of Amylose

A
o Alpha glucose
o 1-4 glycosidic bonds
o Unbranded glucose polymers
o Forms helix shape - compact
o Insoluble in water
o Long chain glucose
19
Q

Features of Amylopectin

A
o Alpha glucose
o 1-4 and some 1-6 glycosidic bonds
o Branded glucose polymers
o Side branches every 25 
o More soluble
o More accessible bonds for quicker release of glucose
20
Q

Features of Glycogen

A

o Similar structure to amylopectin; 1-6 glycosidic bonds- branded structure.
o Stored as small granules (muscles and liver)
o Less dense/soluble than starch and broken down more rapidly
o Higher metabolic requirements of animals compared to plants
o Good for storage

21
Q

Features of Cellulose

A

o Formed from alternate (upside down) beta glucose molecules
o Straight and unbranched
o Create strong and insoluble fibres to form cell walls
o Necessary for a healthy digestive system

22
Q

Features of Triglycerides

A

o Made of one glycerol and three fatty acids
o Ester bonds formed between the fatty acids and glycerol during esterification (water lost) - a condensations reaction
o Can be saturated or unsaturated

23
Q

What does it mean for a molecule to be Saturated?

A

A saturated molecule has no double bonds between C atoms and is usually in a solid state.

24
Q

What does it mean for a molecule to be Unsaturated?

A

An unsaturated molecule has at least one double bond between C atoms, giving them a kink meaning they are liquid at room temperature as they can’t be as compact.

25
Q

Features of Phospholipids

A

o Modified triglycerides, which have an extra phosphate instead of fatty acid - negatively charged so its soluble in water (hydrophilic)
o Non polar tail (hydrophobic)
o Form a layer on water to make them surfactants
o Forms a phospholid bilayer to form a cell membrane.

26
Q

Features of Cholesterol

A

o Manufactured in the liver and intestines
o Important in forming cell membranes
o Regulates the fluidity by keeping the membrane at a low temperature and stopping them turning liquid

27
Q

7 Biological roles of Lipids

A
o Membrane formation and hydrophobic barriers
o Hormone production
o Electrical insulation
o Waterproofing
o Thermal Insulation
o Cushioning
o Buoyancy
28
Q

What test can you use to test for Lipids?

A

Emulsion test using ethanol.