B1.3 Flashcards
Why is respiration essential for living organisms?
It occurs in every cell to supply energy (ATP) to cells.
What type of reaction is respiration?
An exothermic reaction — it releases energy.
What are the two types of respiration?
Aerobic respiration and anaerobic respiration.
Does aerobic respiration use oxygen?
Yes
Where do most of the reactions of aerobic respiration occur?
In the mitochondria.
What is the word equation for aerobic respiration?
Glucose + Oxygen → Carbon dioxide + Water
Write the balanced symbol equation for aerobic respiration.
C₆H₁₂O₆ + O₂ → CO₂ + H₂O
Does aerobic respiration yield more or less energy than anaerobic respiration?
More — it yields the most energy.
When does anaerobic respiration occur?
When there isn’t enough oxygen, such as during intense exercise (e.g. sprinting).
Is anaerobic respiration efficient in terms of energy yield?
No — it yields less energy than aerobic respiration.
What is the word equation for anaerobic respiration in animals?
Glucose → Lactic acid
What is the word equation for anaerobic respiration in yeast and plants (fermentation)?
Glucose → Ethanol + Carbon dioxide
What is fermentation used for in industry?
To make bread and alcoholic drinks.
Is the oxidation of glucose complete in anaerobic respiration?
No — it is incomplete, which is why less energy is released.
What type of biological molecule is starch?
A carbohydrate polymer made from simple sugars.
What are the monomers of carbohydrates?
Simple sugars.
What enzyme breaks down starch, and what is the product?
Amylase breaks down starch into maltose.
What is maltose?
A simple sugar that can be absorbed into the blood to provide energy.
How is glucose stored in the body?
Glucose is converted to glycogen.
What enzyme builds glucose into glycogen?
Glycogen synthase.
What is the function of glycogen?
It acts as an energy store.
What are proteins made of?
Proteins are polymers made from amino acid monomers.
What enzymes break down proteins?
Protease enzymes.
Where do proteases act in the body?
In the stomach and small intestine.
How are new proteins built in the body?
By protein synthesis using amino acids.
What are lipids broken down into?
Glycerol and three fatty acids.
What enzyme breaks down lipids?
Lipase enzymes.
What is the role of bile in lipid digestion?
Bile emulsifies fat — it breaks large fat molecules into smaller droplets.
Why is emulsification by bile important?
It increases the surface area for lipase enzymes to work more effectively.
