respiration Flashcards
What is respiration?
process which releases energy stored in molecules like glucose, through series controlled reactions
What is energy from respiration used for?
to synthesise molecules of ATP from ADP and inorganic phosphate
What is ATP used for?
hydrolysed to release energy needed for biological processes
What is metabolism
collectively all of the chemical processes which occur inside an organisms cells
What is an anabolic reaction?
large molecules synthesised from smaller ones using energy
What is a catabolic reaction?
large molecules broken down to smaller molecules releasing energy
What type of molecule is ATP?
phosphorylated nucleotide
Properties of ATP?
stable and easily transported, but is readily broken down by enzymes, small manageable amounts of energy
How do heterotrophs obtain energy?
consumption of food, in lipids and carbohydrates
How is energy stored in mammals?
as glycogen or in adipose tissues (fats)
How many ATP does one molecule of glucose produce?
32
What types of energy does hydrolysis of ATP release?
chemical and heat
Why is heat energy from hydrolysis of ATP useful?
keeps organisms warm and allows enzyme controlled reactions to take place at optimum temperature
What is the word equation for respiration?
glucose + oxygen –> carbon dioxide + water + ATP
What is the symbol equation for respiration?
C6H12O6 + 6O2 -> 6CO2 + 6H2O + 38 ATP
What is energy needed for?
all metabolic reactions/biological processes
Why do mammals need to maintain body temperature?
to keep optimum temp for biological processes and enzymes
How does SA:V ratio relate to heat loss and respiration?
lower SA:V ratio in larger animals means less heat loss and slower rate of respiration, and vice versa
Describe the structure of ATP
Adenosine and three phosphates
What is adenosine?
adenine plus ribose
What are the four main stages of respiration?
glycolysis, link reaction, krebs cycle, electron transport chain
Two types of transport which require ATP?
active transport, endo/exocytosis
Examples of processes ATP is used for
synthesis large molecules, cell division, transport
Where does glycolysis occur?
cytoplasm
Where does the link reaction occur?
matrix of mitochondria
Where does the krebs cycle occur?
matrix of mitochondria
Where does oxidative phosphorylation occur?
cristae of mitochndria
Is glycolysis aerobic or anaerobic?
anaerobic (does not need oxygen)
Which coenzyme is involved in glycolysis?
NAD
What is the role of reduced NAD?
oxidises substrate and becomes reduced gaining two protons during glycolysis, link and krebs, carries them to mitochondria cristae for oxidative phosphorylation
What is NAD made up of?
non-protein, made of two ribose sugars, nicotinamide, adenine and two phosphoryl groups
What happens to NAD after oxidative phosphorylation?
becomes oxidised and can be used again in glycolysis, link and krebs
What are the two stages of glycolysis?
phosphorylation and oxidation
where does glycolysis occur
cytoplasm
Describe the process of phosphorylation in glycolysis
2 phosphate groups from hydrolysis of 2 ATP added to glucose to form hexose bisphosphate
What are the products of glycolysis?
2 pyruvate, 2ATP (net), 2 reduced NAD
What happens to hexose bisphosphate in glycolysis?
splits into two 3C compounds, triose phosphate
Describe the process of oxidation in glycolysis
both TP loses two H atoms to NAD to become reduced NAD, lose two phosphates each, bind to ADP to produce 4ATP, produces 2 pyruvate molecules
What is the product of oxidation in glycolysis?
pyruvate
What is the net production of ATP in glycolysis?
2ATP
What is the end product of glycolysis?
2 pyruvate
Describe the whole process of glycolysis
glucose (6C) phosphorylated using 2ATP to form hexose biphosphate (6C). This splits into 2 triose phosphates (3C).
They are converted to 2 pyruvate molecules by oxidative dehydrogenation
- 2 molecules of NADH (reduced NAD) produced
- 4 ATP molecules produced
- net production 2 molecules of ATP
What happens if no oxygen is available after glycolysis?
anaerobic respiration continues
Describe the structure of mitochondria
Double membrane forms envelope. Inner membrane folded into cristae, with embedded electron carriers and protein channels. Matrix is fluid filled space between cristae
What does the matrix of mitochondria contain? (5)
mitochondrial ribosomes, DNA and enzymes for link and krebs, coenzymes NAD and FAD, oxaloacetate
Where does the link reaction take place?
matrix of mitochondria