Respiration

(a) outline why plants, animals and microorganisms need to respire, with reference to active transport and metabolic reactions;

(b) describe, with the aid of diagrams, the structure of ATP;(c) state that ATP provides the immediate source of energy for biological

processes;(d) explain the importance of coenzymes in respiration, with reference to NAD

and coenzyme A;

Hydrogen carbonate indicator is sensitive to levels of carbon dioxide (changes in pH)

• Very low levels PURPLE

• Very high levels YELLOW

• Normal atmospheric levels RED

Can you explain the results?

• TUBE 1: EMPTY – CONTROL

• TUBE 2: A LEAF• TUBE 3: A

WOODLOUSE • TUBE 4: A LEAF

AND A WOODLOUSE

1 2 3 4

Breathing and Respiration – same thing?

Respiration

• Oxidative breakdown of sugars or other organic molecules (fats, proteins) in living cells. Energy stored in these organic molecules is released to make ATP. Respiration requires the uptake of oxygen and produces carbon dioxide and water as waste products.

Aerobic Respiration

Anaerobic Respiration

Anaerobic Respiration

Energy

• Cannot be created or destroyed. NEVER refer to energy being produced. Respiration releases energy to produce ATP.

• Measured in joules or kilojoules

ATP

H

What do we need ATP for?

• Active transport

• Secretion

• Endocytosis

• Synthesis of large molecules from smaller ones eg proteins

• DNA replication and organelle synthesis

• Movement eg flagella, cilia

• Activation of chemicals eg phosphorylation of glucose

Metabolism

• Anabolism – large molecules synthesised from smaller ones

• Catabolism – large molecules are hydrolysed to make smaller ones

Coenzymes• Small molecule tightly associated with an enzyme that

participates in the reaction that the enzyme catalyses, often by forming a covalent bond to the substrate.

Why are coenzymes needed?

• Coenzymes help dehydrogenase enzymes carry out oxidation reactions of respiration. Hydrogen atoms are combined with coenzymes such as NAD. These carry the hydrogen atoms to the inner mitochondrial membrane.

• P83 Role of NAD and Coenzyme A