University:
College
Course:
College Chemistry
Academic year:

2023
Views:

457

Pages:

4
Author:

anon

Carbohydrates, lipids and proteins Distinguish between organic and inorganic compounds ➢ Organic compounds – contains a carbon backbone ➢ Inorganic compounds – don’t have a carbon backbone Identify amino acids, glucose, ribose and fatty acids from diagrams showing their structure Amino Acid – difference lies in the R group since it is variable so there are different types of amino acids Glucose ● All carbohydrates have a general formula CnH2nOn ● Monosaccharides, disaccharides and polyssacharides ● Tritose (3), pentose (5), hexose (6) (depending on how many carbons the sugar has) Ribose (pentose) Fatty acids ➢ Building blocks of lipids (along with glycerol) ➢ Monoglyceride, diglyceride, triglyceride depending on the number of fatty acid molecules it is attatched to ➢ They are both hydrophobic List three examples each of monosaccharides, disaccharides and polysaccharides Monosaccharides ● Glucose ● Galactose ● Ribose ● Fructose Dissacharides ● Maltose (glucose + glucose) ● Lactose (glucose + galactose) ● Sucrose (glucose + fructose) Polysaccharides ● Starch (glucose chain) ● Cellulose (glucose) ● Glycogen (glucose) State one function of glucose, lactose and glycogen in animals, and of fructose, sucrose and cellulose in plants ➢ Glucose – short term energy source, used for aerobic and anaerobic respiration ➢ Lactose – found in lactating animals and provides energy to infants before they are weaned ➢ Glycogen – longer term energy store which can be broken down quickly ➢ Fructose – used to make fruits to attract animals to disperse seeds and to make sucrose ➢ Sucrose – converted from glucose to be transported around the plant ➢ Cellulose – used to make cell walls of plants Outline the role of condensation and hydrolysis in the relationships between monosaccharides, disaccharides and polysaccharides; between fatty acids, glycerol and triglycerides; and between amino acids and polypeptides ➢ When building up larger molecules from smaller subunits water is produced and they are known as condensation reactions ➢ Known as condensation polymerization when a polysaccharide is formed from monosaccharides ➢ Polypeptide is formed when many condensation reactions take place and also known as condensation polymerization ➢ The maximum number of condensation reactions is 3 for lipids (triglyceride) so it doesn’t undergo polymerization condensation ➢ When larger molecules are broken down into smaller subunits water is needed, these reactions are known as hydrolysis reactions ➢ Needs water to occur State three functions of lipids ➢ Energy store and metabolic water source ➢ Subcutaneous fat as thermal insulation ➢ Waterproofing of hair and feathers Compare the use of carbohydrates and lipids in energy storage ➢ Lipids = 38kJ/g ○ Less dense (half the mass of carbohydrates) ○ Long term energy sources for plants and animals ○ Undergo more reactions than carbohydrates before they can be used as a substrate for respiration ○ Carbohydrates = 17kJ/g ■ Monosaccharide is the immediate substrate used in respiration ■ Starch is a longer term energy store that needs to be broken down, but not through as many reactions as lipids