QUESTION 1
1.1. Define Kinetic energy.
Kinetic energy is the energy an object possesses due to its motion. The amount of kinetic energy
depends on both the mass of the object and its velocity. The faster an object moves, or the heavier it
is, the more kinetic energy it has.
1.2. Explain how energy is transferred in an ecosystem.
In an ecosystem, energy is transferred primarily through food chains and food webs. Plants capture
solar energy through photosynthesis and convert it into chemical energy. This energy is then passed
along to herbivores when they eat the plants, and to carnivores when they consume herbivores.
Decomposers also play a role in breaking down dead organisms, releasing energy back into the
ecosystem.
1.3. What is the main purpose of photosynthesis in plants?
The main purpose of photosynthesis in plants is to convert light energy, typically from the sun, into
chemical energy stored in glucose. This process allows plants to produce their own food, which
provides energy for growth and development.
1.4. What is cellular respiration?
Cellular respiration is the process by which cells break down glucose (or other organic molecules) to
produce energy in the form of ATP. This occurs in the mitochondria of eukaryotic cells and is
essential for maintaining cell functions and overall energy balance in organisms.
1.5. Compare aerobic and anaerobic respiration.
Aerobic respiration occurs in the presence of oxygen and produces a large amount of energy,
typically yielding up to 38 ATP molecules per glucose molecule. In contrast, anaerobic respiration
occurs in the absence of oxygen and is less efficient, producing only 2 ATP molecules per glucose
molecule. Additionally, anaerobic respiration results in the production of by-products such as lactic
acid in animals or ethanol and carbon dioxide in yeast, while aerobic respiration produces carbon
dioxide and water.
1.6. What is the role of ATP in cellular processes?
ATP (adenosine triphosphate) serves as the primary energy carrier in cells. It provides energy for
various cellular processes, including muscle contraction, protein synthesis, and active transport
across membranes. When ATP is broken down into ADP and inorganic phosphate, it releases energy
that is used by cells to perform work.