ATP and mitochondria

Question 1

why do organisms need energy?
what is the acronym

Answer 1

1. Movement = muscle contraction, movement of cilia, flagella and undulipodia, movement of chromosomes in cell division, moving organelles along cytoskeleton threads via motor proteins
2. Active transport= energy needed to move some molecules or ions across cell surface membranes against a concentration gradient e.g sodium potassium pumps
3. Metabolic processes= small to large molecules, synthesis of new chemical bonds e.g sugars- polysaccharides; amino acids to proteins; DNA replication, synthesis of organelles before cell division, maintaining body temperature for optimum enzyme reactions
4. Bulk movement of large molecules into/out of cells by exocytosis/endocytosis e.g secretion

5.Activation of molecules. When a phosphate molecule is transferred from ATP to another molecule it makes it more reactive so lowering activation energy of the molecule allowing enzyme catalysed reactions to happen more readily
MAMBA

Question 2

what does ATP stand for what is it’s structure

Answer 2

adenosine triphosphate
-ribose sugar, adenine base. 3 phosphates

Question 3

what bond links the 3 phosphates in ATP

Answer 3

a high energy bond, phosphoanhydride

Question 4

describe the ADP to ATP reaction

Answer 4

-reversible
-ATP-hydrolysed- ADP + P -condensation= ATP

Question 5

why is ATP a better source of energy than glucose

Answer 5

-small controlled release of energy = less energy loss
-immediate energy source
-releases small packets of energy

Question 6

describe the roll of ATP in the cell

Answer 6

-transfer energy
-phosphates can be removed by hydrolysis
-to release 30kj energy
-energy released in small packets for metabolism

Question 7

what are the three methods of synthesising ATP

Answer 7

-Substrate level phosphorylation = when a phosphate group is directly transferred from one molecule to another

-oxidative phosphorylation= where energy carried by electrons from reduced coenzymes is used to make ATP

-phosphorylation=when phosphate is added to a molecule using light

Question 8

what are the components of the mitochondria and what happens at each component

Answer 8

-outer membrane= compartmentalisation with ideal conditions for aerobic respiration

-inner membrane= phospholipid bilayer with channel protein to let pyruvate in, contains electron transport chain and ATP synthase, impermeable to hydrogen ions

-matrix= contains enzymes, substrate and coenzyme NAD for Kerbs cycle, link reaction also takes place here, contains mitochondrial DNA

-cristae = increase surface area available for oxidative phosphorylation, ATPsynthase particels on them