NST1502 Assignment 4 2025 (Answer Guide) - Due 2 October 2025

NST1502 Assignment 4 2025 (Answer Guide) - Due 2 October 2025 QUESTION 1 1.1 Define Kinetic energy. (2) Kinetic energy is the energy an object possesses due to its motion. It is directly proportional to the mass of the object and the square of its velocity, expressed mathematically as KE=12mv2KE = frac{1}{2}mv^2KE=21mv2 (Young & Freedman, 2019). 1.2 Explain how energy is transferred in an ecosystem. (2) Energy in an ecosystem flows through food chains and food webs, beginning with producers that capture solar energy through photosynthesis. This energy is then transferred to herbivores and subsequently to carnivores and decomposers, with some energy lost as heat at each trophic level (Odum & Barrett, 2020). 1.3 What is the main purpose of photosynthesis in plants? (2) The primary purpose of photosynthesis is to convert light energy into chemical energy stored in glucose molecules, which serve as food for the plant and provide energy to sustain life processes. It also releases oxygen as a byproduct, essential for most living organisms (Taiz et al., 2018). 1.4 What is cellular respiration? (2) Cellular respiration is the biochemical process by which cells break down glucose and other organic molecules to produce ATP, the usable energy currency of the cell, in the presence or absence of oxygen (Nelson & Cox, 2017). 1.5 Compare aerobic and anaerobic respiration.