3 - Biological Molecules Flashcards
What is a polar molecule? Give an example.
A molecule with a slight positive charge at one end (𝛿+) and a slight negative at the other (𝛿-). eg. water
What bond is formed between 2 monosaccharides in a condensation reaction?
glycosidic
Name the bond holding amino acid monomers together
peptide
What reaction breaks polysaccharides into their constituent parts? (What are the additional reactants/products)
Hydrolysis reaction
you must add water
Give 3 examples of globular proteins
- enzymes
- antibodies
- hormones
Water is a solvent. How does water affect reactions?
increases the rate of reaction (more particles to collide with and change direction)
Glucose, fructose and galactose are all what type of sugars?
Hexose monosaccharides
Water helps control the temperature in our cells. What 2 properties help it do this?
High specific heat capacity (a buffer for temperature change)
High latent heat of vaporisation (cooling effect through evaporation)
α-glucose + α-glucose –>
maltose
Are polar molecules hydrophilic or hydrophobic? How can we tell?
Hydrophilic, they dissolve in water
What is the molecular formula of galactose?
C₆H₁₂O₆
What happens to polar molecules in water? Why is this important?
- All polar molecules dissolve in water
- Water can therefore be used as a solvent to transport polar molecules in and out of cells
Describe the structure of amylopectin
- polymer of glucose (1,4 glycosidic bonds)
- branched (1,6) glycosidic bonds
A chain of β-glucose molecules makes what?
cellulose
A chain of α-glucose molecules makes what?
starch
What are the 2 types of starch?
Amylopectin and amylose
Disaccharides are made through what type of chemical reaction? (what additional products/reactants are needed?)
condensation (also makes water)
What type of protein (shape) is insulin? Why does it do this and what bonds are formed?
- globular
- hydrophobic components protected from aqueous environments of the blood or the cell
- hydrophilic and hydrophobic interactions
Define isomer
compounds with the same moleclar formulae but different arrangements (structural formulae) and therefore different properties
Which type of starch hydrolyses more quickly? Why?
Amylopectin
-branched, therefore, more accessible bonds to hydrolysed at one time
Describe the structure of amylose
- polymer of glucose
- helical
- unbranched
Water’s polarity means it has _____ properties
cohesive
glucose + fructose –>
sucrose
glucose + galactose –>
lactose
Describe the structure of an amino acid
- Central carbon atom
- H atom
- Amine group (NH3)
- Carboxylic acid functional group (COOH)
- R group
What are the 4 types of bonds between proteins monomers? (tertiary structure)
- hydrogen
- ionic
- disulfide bridges
- hydrophillic and hydrophobic interactions
What type of sugar is maltose and how is it made (reactants and type of reaction)?
disaccharide
α-glucose + α-glucose
condensation reaction
What makes a protein have a quarternary structure?
2 or more seperate polypeptide chains
What elements do nucleic acids contain?
CHONP
What elements do carbohydrates contain?
CHO
What elements do proteins contain?
CHONS
What elements do lipids contain?
CHO
What is the structure of a triglyceride?
Glycerol backbone with 3 fatty acid groups coming off
Suggest why a specific fatty acid may be liquid at room temperature.
It is unsaturated (C=C) casuing kinks, unable to pack as tightly together
What is a fatty acid?
Long polymers of carbon and hydrogen
with a carboxyl group at the end (-COOH)
What bond is present between each glycerol and fatty acid in a triglyceride?
An ester bond
How many ester bonds are present in a triglyceride
3
Lipids are short-term/long-term energy stores
Lipids are long-term energy stores
What is the structure of a phospholipid?
Phosphate ion with 2 fatty acid branches
Which enzyme catalyses the addition of amino acids in the ribosomes?
Peptidyl transferase