What needs energy?• So far we know all

animals (heterotrophs) and plants (autotrophs) need energy.

• So far we have learned that certain cell processes require energy:– Active Transport– Facilitated Diffusion– Cell Division– Cilia & Flagella– Enzymes– Production and storage of

proteins• The Mitochondria

supply the energy for the cell

Energy - ATP

• Quick Energy comes from ATP

• Adenosine Triphosphate• Composed of an Adenine

Molecule, a 5 Carbon Ribose Sugar with 3 Phosphate groups attached

• Keep in mind, the Phosphate groups are negatively charged and 3 charged groups will not like to be next to one another – Like North & North poles on

a magnet

The covalent bonds that unite the phosphate units in ATP are high-energy bonds. This is where the energy is stored. When an ATP molecule is broken down by an enzyme, the third (terminal) phosphate unit is released as a phosphate group, or ion.

When this happens, approximately 7.3 kilocalories of energy are released. (A kilocalorie equals 1,000 calories.) This energy is made available to do the work of the cell.

Energy – ADP and AMP

• When the bond in a molecule of ATP is broken, there the most energy released because 3 charged phosphates do not like to be close to one another

• A 2 Phosphate molecule is called ADP, it has less energy because there are only 2 phosphate groups repelling one another

• A 1 Phosphate molecule is called AMP, it has the least energy because there is only 1 phosphate group.

• Note: ATP is not a good way of storing energy long term, sugar can store 90 times the chemical energy of ATP.

http://biologyinmotion.com/atp/index.html

http://www.stolaf.edu/people/giannini/flashanimat/metabolism/atpsyn1.swf

Energy Recycling makes happy proteins!

• An enzyme, ATP Synthase uses a proton (H+) gradient in the Mitochondria to add phosphorus back to ADP to create ATP.

• http://www.sp.uconn.edu/~terry/images/anim/ATPmito.html

• This system of ATP/ADP is good because…– Relieves the cell of having to store

all the ATP it needs– ADP can be used as a resource for

cell activities that do not require as much energy (as ATP would provide.)

http://www.science.smith.edu/departments/Biology/Bio231/etc.html

http://vcell.ndsu.nodak.edu/animations/atpgradient/movie.htm