, QUESTION 1
1.1 Define Kinetic energy. (2)
Kinetic energy is the energy that an object possesses due to its motion. It depends on the
object’s mass and velocity.
1.2 Explain how energy is transferred in an ecosystem. (2)
Energy is transferred in an ecosystem through the food chain or food web. Producers
(plants) capture solar energy, which is then passed to herbivores, carnivores, and
decomposers as organisms feed on one another.
1.3 What is the main purpose of photosynthesis in plants? (2)
The main purpose of photosynthesis is to convert light energy from the sun into chemical
energy stored in glucose, which provides food and energy for the plant and other organisms
in the ecosystem.
1.4 What is cellular respiration? (2)
Cellular respiration is the biochemical process by which cells break down glucose in the
presence (or absence) of oxygen to release energy in the form of ATP, which powers cellular
activities.
1.5 Compare aerobic and anaerobic respiration. (4)
• Aerobic respiration requires oxygen and produces a large amount of ATP (around
36–38 molecules per glucose), with carbon dioxide and water as by-products.
• Anaerobic respiration occurs without oxygen, produces much less ATP (only about
2 molecules per glucose), and results in by-products such as lactic acid (in animals)
or ethanol and carbon dioxide (in yeast and plants).
•
1.6 What is the role of ATP in cellular processes? (2)
ATP acts as the main energy currency of the cell. It provides energy for essential cellular
processes such as active transport, muscle contraction, biosynthesis of macromolecules,
and cell division.
1.1 Define Kinetic energy. (2)
Kinetic energy is the energy that an object possesses due to its motion. It depends on the
object’s mass and velocity.
1.2 Explain how energy is transferred in an ecosystem. (2)
Energy is transferred in an ecosystem through the food chain or food web. Producers
(plants) capture solar energy, which is then passed to herbivores, carnivores, and
decomposers as organisms feed on one another.
1.3 What is the main purpose of photosynthesis in plants? (2)
The main purpose of photosynthesis is to convert light energy from the sun into chemical
energy stored in glucose, which provides food and energy for the plant and other organisms
in the ecosystem.
1.4 What is cellular respiration? (2)
Cellular respiration is the biochemical process by which cells break down glucose in the
presence (or absence) of oxygen to release energy in the form of ATP, which powers cellular
activities.
1.5 Compare aerobic and anaerobic respiration. (4)
• Aerobic respiration requires oxygen and produces a large amount of ATP (around
36–38 molecules per glucose), with carbon dioxide and water as by-products.
• Anaerobic respiration occurs without oxygen, produces much less ATP (only about
2 molecules per glucose), and results in by-products such as lactic acid (in animals)
or ethanol and carbon dioxide (in yeast and plants).
•
1.6 What is the role of ATP in cellular processes? (2)
ATP acts as the main energy currency of the cell. It provides energy for essential cellular
processes such as active transport, muscle contraction, biosynthesis of macromolecules,
and cell division.
