B1 Flashcards
What is a macromolecule?
Macromolecules are larger molecules, made of many repeating subunits. To be classified as a macromolecule, it is generally made of a very large number of molecules and weighs over 10,000 atomic mass units.
What is a monomer?
A monomer is the repeating small units (molecules) that make up polymers and thus macromolecules. Different monomers= unique monomers
What is a condensation reaction and how is it done?
A condensation reaction involves the formation of a covalent bond between two monomers. This is done by removing a hydrogen from one monomer and a hydroxyl group from the other.
What is the result of a condensation reaction?
Dimer- two monomers bonded together. This will become a polymer when other condensation reactions occur
Water is a waste product
What is hydrolysis?
Hydrolysis is the opposite of condensation reactions- begins with polymers and water and ends with stable monomers.
Water is split to form H and OH to stabilise the monomers once separated.
What features of carbon makes it able to form many unique compounds?
- Has 4 valence electrons- effective at forming covalent bonds with other atoms, including other carbons
- Can form 4 covalent bonds- these can be single or double bonds, meaning it can form a variety of compounds
- Can form long chains and rings- diverse structural compounds
What is the monomer of carbohydrates?
Monosaccharides
What is the monomer of lipids?
Fatty acids plus a glycerol or phosphate group
What is the monomer of proteins?
Amino acids
What is the monomer of nucleic acids?
Nucleotides
What are some examples of body processes that use condensation reactions?
- Building body tissues
- Protein synthesis- most crucial role of every cell
- When energy is stored in larger carbohydrates
What are some examples of body processes that use hydrolysis reactions?
- Digestion- consuming polymers and hydrolise using digestive enzymes to turn them into monomers for use in the body
Why is water produced in condensation reactions?
- Previously stable monomers must become reactive
- This is done by removing something from each monomer
- To create a safe waste product, a hydrogen is removed from one monomer and a hydroxyl is removed from the other monomer
- These combine to make water!
What role does water play in hydrolysis reactions?
- After breaking the bond in a polymer, the monomers would be reactive and unstable
- They would just reconnect if not made stable
- To do this, water is split and the H and OH reattatch to either monomer
- This makes the monomers chemically stable seperate
What is a monosaccharide?
- Means ‘one sugar’- the monomer of all carbohydrates
- Most have 5 or 6 carbons and form rings in aqueous solutions
What are some examples of monosaccharides?
Ribose, deoxyribose and glucose
What are polysaccharides/ complex carbohydrates?
- Means ‘many sugars’
- When many monosaccharides are chemically bonded together
- They are a form of energy storage as they can be broken down into monosaccharides
- They perform important roles in structures of cells
What is cellulose/ dietary fibre?
- Cellulose is a polysaccharide that makes the cell wall of plants.
- Made of a long chain of alternating beta glucose molecules
- They make long straight fibres ideal for structures, and make bonds between chains
- Most organisms cannot break down
What is a glycoprotein?
- A carbohydrate chain bonded to a protein
- They are found in cell membranes for cell recognition and communication
- A ‘conjugated carbon protein’- a carbohydrate bonded to a protein
What is the difference between a pentose and a hexose sugar?
- All sugars have a carbon backbone
- Pentose sugars have a 5 carbon backbone e.g fructose, ribose- C(5)H(10)O(5)
- Hexose sugars have a 6 carbon backbone e.g glucose- C(6)H(12)O(6)
What makes glucose a polar molecule?
- Hydroxyl bonds (between the O and the H) are polar
- As glucose has 5 OH groups, it is a polar molecule
How does the polarity of glucose determines the polarity?
- Molecular stability- due to covalent bonds
- High solubility in water- due to polarity
- Easily transported- due to solubility (caused by polarity)
- Yields high energy (ATP) when oxidised (broken apart)- due to strong covalent bonds
What is the difference between alpha and beta glucose?
- They have the same elements
- When in a ring structure (aqueous), the orientation of the hydroxyl and hydrogen on carbon 1 rotate
- Most polymers use alpha glucose, but beta glucose is used in cellulose
What makes starch and glycogen ideal structurally for energy storage?
- Long chains of glucose molecules
- They form coils or chains which make them compact storage molecules
- Fairly insoluble in water due to large size, makes them good for storage
- Bonds between glucose molecules can break easily by hydrolysis into monosaccharides for cellular respiration
- Note: plants= starch, animals= glycogen
What is the difference between amylose and amylopectin?
- Amylose- glucose are connected to adjacent glucose, creating a linear chain which twists into a helix when long
- Amylopectin- additional bonding on top of glucose between c1 and c6 creates a branched structure
What is the specific role of ABO glycoproteins?
- ABO glycoproteins identify ones own blood type
- Different types of ABO antigens that distinguish between Type A, B, O and AB blood
- Based on that, our immune system builds antigens to OTHER blood types (not our own)
- This is important as it determines which blood is compatible for transfusion
Draw the structure of glucose
Explain the structure and function of amylose
Structure: Straight chain of alpha glucose, made of only 1-4 linkages. Overall helix shape
Function: Long term storage in plants- makes up 20% of plant starch
Explain the structure and function of amylopectin
Structure: Branched chain of alpha glucose, has 1-4 linkages and some 1-6 linkages.
Function: Long term storage in plants- makes up 80% of plant starch
Explain the structure and function of glycogen
Structure: highly branched chain of alpha glucose, has 1-4 linkages and lots of 1-6 linkages.
Function: Short term storage for animals. In humans, it is stored in the liver
Explain the structure and function of cellulose.
Structure: Straight chain of alternating oriented beta glucose (right way up then upside down), has all 1-4 linkages.
Function: Structural polysaccharide- strong and insoluble fibres, used for plant cell walls. Don’t provide energy- most organisms cannot digest.