(J) how properties of triglycerdies, phospholipids and cholesterol relate to their function

What can phospholipids form

Phospholipid monolayer when in water (heads. In with tails sticking out)

Or Phospholipid bilayer with hydrophobic tails in centre (away from water) and he heads protecting them from the water

What is the importance of the bilayer

Allows cell membrane to control what gos in and out the cell and the fluidity

What dos it mean for the phospholipid to have a hydrophobic and hydrophilic side

ITS AMPHIPATHIC

What is the importance of the hydrophobic and hyrdrophilc sides?

Allows the cell membrane to form the bilayer

Tails creates a barrier that speerates the inside of the cell and the environment

What do the heads allow for it to do

Exchange substances between cell and its environment and cell communication

What do phospholipids play a role in

Cell signalling

Creating hydrophobic barriers

Membrane formation

What is the importance of the triglyceride

It’s hyropdhbic and non polar so its good for waterproofing ( for example bird feathers)

Important in lng term energy storage

• Thermal insulation

• Cushioning fo vital organs ( like heart or kidneys)

• Buoyancy for aquatic animals ( the ability to float) for whales e.g

What are some properties of sterols

Complex a logo based on 4 carbon ring structure with an OH group at the end

Have dual hydrophobic and hyrdrophilic sides like the phospholipid

The OH = polar

Rest of molecule is hydrophilic

How does the cholesetrol position itself in the cell membrane

The hydrophilic hydroxyl group can interact it’s the head group of phosphilipid

The rest of cholesterol interacts with the fatty acids

Therefore it’s positioned between phospilpids

What is the importance of the cholesterol

Due to its position between phosplipids it addds stability to the cell membrane

Regulates fluidity

Its used as a starting point for a range of hormones (e.g oestrogen or testosterone)

Due to cholesterol being the starting point the hormones also find its way through the celllmemnarne like the cholesterol

Used in the body to make up vitamin d against UV

Used to produce bile in the liver which speeds up digestion of lipids