F214 RESPIRATION 1: THE FUNDAMENTALS
Complete the notes sheets below. Where you see a blank
(…………………..), decide which word/phrase is most appropriate.
Respiration is a series of ……………………….-catalyzed reactions that release
……………………. from ………………………. molecules in order to synthesize
……………………… . ………………………… respiration, which involves the participation of
oxygen, consists of four distinct but linked stages: ………………………. ,
………………………….. , …………………………………, and the …………………………………. .
What is respiration?
DEFINITION: Respiration
……………………………………………………………………………………………………………………………
……………………………………………………………………………………………………………………………
……………………………………………………….....................................................................
DEFINITION: Energy
……………………………………………………………………………………………………………………………
……………………………………………………………………………………………………………………………
****REMEMBER*** Energy cannot be created or destroyed, it can only be
converted from one form to another.
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Why respire?
Respiration produces energy for METABOLIC (both ANABOLIC AND CATABOLIC)
reactions such as:
a. ……………………………..: Moving ions and molecules against a concentration
gradient.
b. ……………………………..: Secretion of large molecules.
c. ……………………………..: Movement of large molecules into cells.
d. ……………………………..: Synthesis of large molecules from smaller ones.
e. ……………………………..: Preparing a cell for anaphase.
f. ……………………………..: Powering bacterial flagella, eukaryotic cilia, muscle
contraction and microtubule motors that transport organelles.
g. ……………………………..: E.g. glucose is phosphorylated at the start of
respiration to make it more chemically unstable.
ATP (Adenosine triphosphate)
ATP is a phosphorylated nucleotide. It is commonly referred to as the universal
……………………. ……………………… .
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Add the following labels to the diagram below left and then draw and
label a simplified version showing the basic structure to the right:
Adenine, Adenosine, Ribose, Phosphate groups.
ATP can be …………………….. to form ADP and Pi (……………………………..), releasing
30.6 KJ.mol-1 of energy. It is a …………………………….-lived molecule which is
constantly being hydrolysed and resynthesized.
ATP + H20  ADP + Pi (+30.6 KJ.mol-1)
ATP is derived from …………………………… . We can tell this because the sugar is
………………………. .
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Mitochondria
The diagram shows a mitochondrion. Label the following: Inner
membrane, outer membrane, matrix, intermembrane space, cristae
RESPIRATION ESSENTIALS
1. Oxidation and reduction
***REMEMBER*** OIL RIG
O…………………….
I……………………..
L…………………….
R……………………..
I………………………
G…………………….
Oxidation and reduction are coupled, since if one substrate becomes oxidised,
another must be reduced. Such reactions are called REDOX reactions.
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2. Respiration is a multi-step process. The multitude of reactions that
take place from start to finish can be summarised in four key steps:
a. Glycolysis: Glucose (….C) is broken down to produce 2 molecules of
Pyruvate (….C).
b. The link reaction: Pyruvate is dehydrogenated (………………… is
removed) and decarboxylated (…………………. is removed) and
converted to acetate.
c. Krebs cycle: Acetate is dehydrogenated and decarboxylated.
d. Oxidative phosphorylation: ADP is phosphorylated to ……… .
3. Coenzymes
In the reactions of respiration, coenzymes become …………………. as substrates
become …………………….. . These are necessary because the reactions are catalysed
by inefficient dehydrogenase ………………… . Hydrogen ATOMS are combined with
coenzymes such as NAD (Nicotinamide adenine dinucleotide) to form
………………….. NAD (or NADH). NADH is later split into electrons and protons
(…………. ions) in the inner mitochondrial membranes where they are involved in
oxidative phosphorylation, a process which produces a lot of ……………………. . NAD
is then recycled back into the earlier stages of respiration.
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1. NAD
Sketch and label a simplified version of the structure of NAD (oxidised) in the box
below:
2. Coenzyme A (CoA): Carries acetate groups produced from pyruvate (the
product of glycolysis) during the link reaction onto the krebs cycle.
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