Bio 30
NWRC
Metabolic processes
– all chemical reactions that occur in the body
Two types of metabolic reactions
Anabolism
• larger molecules are made from smaller ones
• requires energy
•
(endergonic)
Catabolism
• larger molecules are broken down into smaller ones
• releases energy
•
-(exergonic)
Energy
• ability to do work or change something
• heat, light, sound, electricity, mechanical energy, chemical energy
• changed from one form to another
• involved in all metabolic reactions
Release of chemical energy
• most metabolic processes depend on chemical energy
• breakdown of glucose generates chemical energy to promote cellular metabolism
• cellular respiration releases chemical energy from molecules and makes it available for cellular use
Anabolism provides the materials needed for cellular growth and repair – free energy is needed
Dehydration synthesis
• type of anabolic process
• used to make polysaccharides, triglycerides, and proteins
• produces water
Catabolism breaks down larger molecules into smaller ones
Releases free energy
• a catabolic process
• used to decompose carbohydrates, lipids, and proteins
• water is used to split the substances
• Adenosine triphosphate
(ATP) is the unit of energy used in all living cells. This molecule is produced and broken down in metabolic processes in all living systems.
• ATP can store and transport the energy we need to do just about everything that we do.
Essentially all metabolic functions of living cells require energy for operation and obtain it directly from stored ATP.
• These molecules can transport energy because phosphate bonds contain a lot of potential energy, which is released when they are broken.
• Energy is stored in the covalent bonds between phosphates, with the greatest amount of energy between the second and third phosphate groups
• ATP is produced by autotrophs during photosynthesis, as described, and is also produced by both autotrophs and heterotrophs during a catabolic process known as cellular respiration.
• In eukaryotic cells, complex cells that possess a nucleus,
ATP is synthesized in the tiny energy factories called mitochondria. In prokaryotes ATP synthesis occurs in the cytoplasm and plasma membrane.
• Adenosine
Triphosphate
• each ATP molecule has three parts:
– an adenine molecule
– a ribose molecule
– three phosphate molecules in a chain
• How it works
• ATP works by losing the endmost phosphate group when instructed to do so by an enzyme.
This reaction releases a lot of energy, which the organism can then use to build proteins, contact muscles, etc . The reaction product is adenosine diphosphate
When the organism is resting and energy is not immediately needed, the reverse reaction takes place and the phosphate group is reattached to the molecule using energy obtained from food or sunlight. Thus the ATP molecule acts as a chemical 'battery', storing energy when it is not needed, but able to release it instantly when the organism requires it. http://www.biologyinmotion.com/atp/index.html
ATP rechargeable battery animation
• When carbohydrates and other foods are consumed by the body, they also contain energy. When they are broken down, the energy is released and, in many cases, the energy is used to reattach the phosphate molecule to the
ADP, turning it back into ATP. Then the cycle of bond-breaking and bond-making begins all over again, alternately releasing and storing energy, as needed. A convenient way to remember the cycle is ATP = ADP + P + Energy http://classes.midlandstech.edu/carterp/Courses/bio225/chap05/lecture1.htm
Animation of carbs, fats, proteins converted into ATP..a MUST WATCH!!!
ATP ANIMATIONS:
• http://www.biologyinmotion.com/atp/index.html
• ATP rechargeable battery animation
• http://www.youtube.com/watch?v=Lx9GklK0xQg
• ATP CYCLE ANIMATION
• http://www.youtube.com/watch?v=qRFE9UtQB10&feature=related
• Cycle animation
• http://www.youtube.com/watch?v=aIMGS0cSoFI
• Advanced animation
• http://www.youtube.com/watch?v=yz4lFeqJPdU&feature=related
• Fascinating view of inner cell; molecules acting like machines