b1.1 carbs and lipids

Covalent Bonds

Carbon forms four covalent bonds with other atoms.

carbon

- forms 4 covalent bonds

- combinations of single and double bonds

- carbs, lipids, proteins, nucleic acids (carbon compounds)

Condensation Reaction

hydroxyl of one molecule and the hydrogen break off to form water and join the two smaller molecules or monomers together.

- polymerization

- protein synthesis

- polysaccharides from monosaccharides

- DNA replication

Hydrolysis

water molecule is added and broken down into a hydroxyl and a hydrogen

- separates macromolecules into smaller molecules (monomers)

- digestion

- cell respiration

Monosaccharides

glucose and ribose

- glucose= hexose sugar (6 sides)

- ribose= pentose sugar (5 sides)

functions of monosaccharides

soluble in water- glucose= polar, dissolves in plasma+ easy transport

- can be oxidized= source of energy when covalent bonds are broken in an oxidation reaction during cellular respiration

- molecular stability= covalent bonds within glucose do not break easily

starch

- (polysaccharide) how glucose is stored in plants

- alpha glucose

- amylose= not branched

- amylopectin= branched

glycogen

- (polysaccharide) how glucose is stored in animals

- alpha glucose

- branched, but more frequently than amylopectin

α-glucose

Glucose with downward bond orientation, (spiral)

- more compact, better storage

- branching helps w storage as well

- add or remove glucose molecules to build and use energy stores

β-glucose

Glucose with alternating bond orientation, structural role.

Polysaccharides

Long chains of monosaccharides for energy storage.

conjugated carbon molecules

macromolecules join to become a single structure w specific functions

- lipid+ protein= lipoprotein

- lipid+ carbohydrates= glycolipid

- carbohydrate+ protein= glycoprotein

glycoprotein

cell id tags in cell to cell recognition for:

- cell to cell communication/signaling

- cell to cell adhesion

- recognition of self vs non self cells (antigens)

blood cells and glycoproteins

glycoprotein present on red blood cells determines compatibility for donating and receiving blood

Cellulose

Plant cell wall component, made of β-glucose.

- alternating pattern= linear structure, tensile strength

- insoluable in water

Lipids

- fats, oils, waxes, steroids

- carbon and hydrogen are non polar covalent bonds

- insoluable in polar solutions (water)

Triglycerides

Fats made of 1 glycerol and 3 fatty acids.

- makes 3 water molecules in the process

- high source of energy storage

- long term energy storage (limitations in transport and breakdown)

Phospholipids

- make up majority of cell membrane

- amphipathic

- 1 glycerol, 2 fatty acids and a phosphate group joined in a condensation reaction, making 3 water molecules

Saturated Fatty Acids

No double bonds, solid at room temperature.

- animal fat

Monounsaturated Fatty Acids

One double bond between carbons

- lower melting point

- liquid at room temperature.

Polyunsaturated Fatty Acids

Multiple double bonds, liquid at room temperature.

Adipose Tissue

- how triglycerides are stored in animals

- fat storage determined by food intake vs energy expenditure

- excellent thermal insulator (animals in cold environments maintain body temp and have a greater amount of adipose tissue)

phospholipid bilayers

phospholipids= amphipathic

- phosphate heads face out (hydrophillic)

- fatty acid tails face away on the inside (hydrophobic)

- forms bilayer

- selectively permeable

- large/polar molecules cannot pass through

Steroid Hormones

- hormones= chemical messengers made up of glands

- steroids= hormone that contains cholesterol, can pass through bilayers easily. affect gene expression

- cholesterol= lipid, hydrophobic

Oestradiol

A steroid hormone involved in female reproduction.

Testosterone

A steroid hormone involved in male reproduction.