Molcell Module 2: Biomolecules

Macromolecules

The most abundant class of chemicals in the cell (apart from water)

Carbohydrate

Macromolecule where C/H/O ratio is 1:2:1

Monosaccharide

Simple sugar

Disaccharide

Two monosaccharides that are covalently bonded

Polysaccharide

Complex sugar or starch composed of many covalently bonded monosaccharides

How do disaccharides form?

When two monosaccharides undergo a dehydration reaction, results in a glycosidic bond between two monosaccharides

What monosaccharides comprise sucrose?

Glucose and fructose

What monosaccharides comprise lactose?

Glucose and galactose

What monosaccharides comprise maltose?

Glucose and glucose

What do sucrose, lactose, and maltose have in common?

They are all water soluble

What do glucose, galactose, and fructose have in common?

They are structural isomers

What is a polysaccharide found in some bacteria?

Cellulose

What are some polysaccharides found in plants?

Starch, cellulose

What is a polysaccharide found in fungi?

Chitin

What are some polysaccharides found in animals?

Glycogen, chitin

What is cellulose?

A linear polysaccharide composed of glucose units that is part of a plant’s cell wall

Microfibrils

Rigid, insoluble bundles of linear chains that are hydrogen bonded to each other. Makes plant cell walls strong

Glycogen

Form of glucose in vertebrates stored in liver and muscle cells

Lipid functions

Energy storage, insulation, hormones, cell membranes

What are fats composed of?

Glycerol and 3 fatty acid chains

What bonds are in a saturated fat?

All single bonds

What bonds are in unsaturated fat?

Has a double bond- can be cis or trans

Saturated fats

No available position for H to bind, usually solid at RT

Unsaturated fats

Double bonds allow for H to bind, usually liquid at RT

Which fat is more harmful to human health?

Trans fats

How are waxes formed?

Esterification of fatty acid chains and long chain alcohols

What are the regions of a phospholipid?

Hydrophilic polar phosphate head, hydrophobic non-polar fatty acid tail

What is the structure of steroids?

4 fused hydrocarbon rings: three 6-member rings and one 5-member ring

Are steroids hydrophobic or hydrophilic?

Hydrophobic

What is the function of cholesterol?

Structure, signaling, and disease

What is the structure of a disaccharide?

Two linked rings