Cell Transport

Organic Compounds Carbohydrates

Sugars – fruits and vegetables

Starches – potatoes, pasta, rice, bread

Break down into glucose (sugar) and used to produce energy.

Lipids – fats, oils and waxes

Rich in energy Stored energy for

later use Cell membrane –

made of lipids

Proteins – amino acids

H O N C 20 common amino

acids Different amino acids Different

arrangement Change the type of

protein formed Meats, eggs, fish,

nuts, beans

                                                                                                                                    

                            

Enzyme – kind of protein Used to speed up

chemical reactions in the body

Each enzyme has a special job

Ex. Saliva – speeds up breaking down of starches into sugar in your mouth

How enzymes work. 1.They are organic

proteins 2.Enzymes are specific;

they only react with specific substances that examples: Lipase (an enzyme)

will only react with lipids(fats,oils),

Amylase will only react with starch,etc.

3. After they do their job, the same enzyme can be used over and over again

Nucleic acids – very long organic substances

C H O N P Instructs cells on

functions of life DNA – passes down info

about organism from parent to offspring

RNA – helps in production of proteins

- found in nucleus and cyto

Control of materials by cells

Selective permeablility – the ability of the cell membrane to allow some materials in and keep others out.

Diffusion As they move, they

move from higher concentration to places of lower concentration.

Equilibrium - Diffusion occurs until all of the particles are evenly distributed.

- keep on moving but maintain that equilibrium

osmosis The diffusion of water

through the cell membrane.

Osmosis is impt b/c 1. Cells contain water

mole. 2. Most cells are

surrounded by water molecules

Water moves from higher concentration to lower concentration

Osmosis Equilibrium exists

when water leaves and enters the cells at the same rate.

Types of transport Passive transport –

movement of particles across cell membrane by diffusion.

- cell does not need to use energy to move the particles.

                                     OSMOSIS

Facilitated diffusion Protein molecules

located in the cell membrane help larger molecules that normally can’t enter the cell membrane.

Carrier proteins Passive transport They act as a gate to

let lg mole into the cell

Facilitated Diffusion

Facilitated diffusion involves the use of a protein to facilitate the movement of molecules across the membrane.  In some cases, molecules pass through channels within the protein.

                                             

Active transport When the cell uses

energy to pass molecules through cell membrane.

Movement occurs from areas of low concentration to areas of high concentration.

Carrier proteins used Opposite of diffusion

Proteins in the MembraneActive transport is usually done

across the cell membrane. Embedded in the lipid bilayer are

proteins.

The proteins are very specific. One protein that moves glucose will not move calcium (Ca) ions. There are hundreds of types of carrier proteins.

Protein joins with the particle to be transported.

Energy from cell is used to move the particles.

Active transport

Endocytosis Some molecules are too large to pass through the cell membrane by active or passive transport.

Large proteins and bacteria enter the cell by becoming enclosed in a part of the cell membrane that folds in to form a sphere

The sphere pinches off- vacuole is made and contents enter cyto

Exocytosis Substances in

small sacs are released at the cell membrane.

The vesicle fuses with the cell membrane and its contents released from the cell.

exocytosis