Biology IFlora

All living things depend on energy What is energy?

Energy – ability to do work Energy is needed in different amounts at

different times

Autotrophs – organisms that make their own food (plants)

Heterotrophs – obtain energy from the foods they consume (Mr. Flora)

** To live…ALL organisms MUST release the energy in sugars and other compounds!

One of the major chemical compounds that cells use to store and release energy is known as adenosine triphosphate – “ATP”

ATP consists of: Adenine (nucleobase) 5 – Carbon sugar 3 phosphate groups** 3 phosphate groups are the key to ATP’s

ability to store and release energy

Adenosine Diphosphate (ADP) Two phosphate groups Cells can store small amounts of energy by

adding phosphate groups to ADP molecules

How is energy released? By the breaking of the chemical bond between

the second and third phosphate groups Cells have the ability to remove phosphate

groups when needed to provide energy Ex: ATP powers cellular activities

** Characteristics of ATP makes it very useful as the basic energy source of ALL cells!

Na/K Pumps Motor proteins Synthesis of nucleic acids and proteins Lightning bug?????

Are cells loaded with ATP they can use??? No!!!!! ATP is a good molecule for transferring

energy, but NOT a good one for long-term storage

A single sugar molecule (glucose) can store more than 90 times the chemical energy of ATP.

** Cells can make ATP from ADP by using energy in foods like glucose!