B1.3 Respiration Flashcards
Carbohydrates are organic molecules that all contain…
carbon, hydrogen and oxygen
Monosaccharides are…
The individual molecules (monomers) that build carbohydrates e.g:
- glucose
- fructose
- galactose
Disaccharides can be formed from…
Two monosaccharides e.g:
- glucose + fructose = sucrose
- galactose + glucose = lactose
- glucose + glucose = maltose
Carbohydrates are normally stored as…
Polysaccharides e.g. starch, glycogen and cellulose.
Proteins are organic molecules that all contain…
Carbon, oxygen, hydrogen and nitrogen.
Proteins are made from…
About 20 amino acid monomers.
Amino acids are linked together by…
Peptide bonds to form polypeptides which form proteins
Protease is…
The enzyme that breakdown proteins into amino acids.
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State the difference between anabolism and catabolism.
- Anabolism = biosynthsis, the building up of larger molecules from small molecules
- Catabolism = biodegregation, the breaking down of large molecules into smaller molecules
State the three enzymes that breakdown the disaccharides maltose, sucrose and lactose.
- Maltase = maltose = glucose + glucose
- Sucrase = sucrose = glucose + fructose
- Lactase = lactose = galactose + glucose
What does the enzyme amylase catalyse?
The breakdown of the polysaccaride starch into the disaccharide maltose.
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Lipids are energy dense organic molecules that all contain…
carbon, oxygen and hydrogen
Lipids are made from…
One glycerol molecule and three fatty acids molecules.
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The enzyme… breaksdown lipids into fatty acids and gylcerol.
Lipase
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What is cellular respiration and what does it do?
- A continually occurring and universal process
- Provides this energy in all living things.
- Exothermic reaction
Cells need the energy released by cellular respiration to carry out all living processes including:
- Movement – energy is needed for muscle cells to contract.
- Biosynthesis – chemical reactions building up molecules
- Thermoregulation – keeping organisms warm
State the main substrate of cellular respiration in animals?
Glucose
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Where does aerobic respiration occurs in eukaryotic cells, including animal and plant cells?
Aerobic respiration occurs in the mitochondria.
Where does anaerobic respiration occurs in eukaryotic cells, including animal and plant cells?
Anaerobic respiration occurs in the cytoplasm.
What is the chemical equation for aerobic respiration?
C6H1206 + 02 → CO2 + H2O + ATP
What is the word equation for aerobic respiration?
Glucose + oxygen → carbon dioxide + water + energy
Why is respiration an oxidation reaction?
Oxygen is used to react with glucose to release energy in the form of ATP.
What does ATP stand for?
Adenosine Triphoshate
Aerobic respiration is a series of enzyme-controlled reactions that can be divided into three main stages:
- Link reaction – Occurs in the matrix
- The Krebs cycle – Occurs in the matrix
- Electron transport chain – Occurs on the inner mitochondrial membrane.
What is glycolysis and where does it take place?
- The first stage in cellular respiration
- Anaerobic stage
- Net gain of 2 ATP
- Takes place in the cytoplasm
What is anaerobic respiration?
Respiration in the abscence of oxygen.
How does the energy released from anaerobic respiration compare to aerobic respiration?
- Anaerobic respiration = 2 ATP
- Aerobic respiration = 38 ATP
What is the word equation for anaerobic respitation in animals?
glucose → lactic acid + ATP
What is the word equation for anaerobic respitation in plants and microorganisms?
glucose → carbon dioxide + ethanol + ATP
What is an ‘oxygen debt’?
- As lactic acid is poisonous to the body it must be broken down using oxygen after anaerobic respiration.
- Heavy breathing after exercise provides extra oxygen to breakdown the lactic acid and the extra oxygen required is known as the oxygen debt.
When does anaerobic respiration take place in animals?
Normally during strenuous exercise when the demand for oxygen by muscles is greater than the oxygen that can be supplied from aerobic respiration.
Anaerobic respiration in yeast is called…
Fermentation
Name two commercial uses of fermentation.
- Bread making
- Brewing