NST1502 Assignment 4
PORTFOLIO
(COMPLETE ANSWERS)
2025 - DUE 2 October
2025
[Document subtitle]
[School]
[Course title]
, NST1502 Assignment 4 PORTFOLIO (COMPLETE ANSWERS) 2025 - DUE 2 October 2025
Course
Natural Science and Technology for classroom II (NST1502)
Institution
University Of South Africa (Unisa)
Book
New Natural Science and Technology
NST1502 Assignment 4 PORTFOLIO (COMPLETE ANSWERS) 2025 - DUE 2 October 2025 ; 100%
TRUSTED Complete, trusted solutions and explanations.
QUESTION 1 1.1 Define Kinetic energy. (2) 1.2 Explain how energy is transferred in an
ecosystem. (2) 1.3 What is the main purpose of photosynthesis in plants? (2) 1.4 What is cellular
respiration? (2) 1.5 Compare aerobic and anaerobic respiration. (4) 1.6 What is the role of ATP
in cellular processes? (2) 1.7 Explain how ATP is synthesized in the mitochondria. (3) 1.8 What
does ADP stand for? (1) 1.9 Explain the process of converting ADP to ATP. (2) 1.10 Insert a
screenshot to show your contributions to one of the engagements in the first unit. (Take this
from the discussion forum based on unit 1) (2) [22]
1.1 Define Kinetic energy. (2)
Kinetic energy is the energy possessed by an object due to its motion. It is directly proportional
to the mass of the object and the square of its velocity.
Formula: KE=12mv2KE = \frac{1}{2} m v^2KE=21mv2
Example: A moving car or a rolling ball has kinetic energy because it is in motion.
1.2 Explain how energy is transferred in an ecosystem. (2)
Energy flows in an ecosystem through food chains and food webs. Sunlight is captured by
producers (plants) through photosynthesis. Herbivores eat the plants, obtaining chemical
energy. Carnivores then eat herbivores, and energy is transferred along trophic levels.
Decomposers break down dead organisms, returning nutrients to the soil but not recovering all
energy, as some is lost as heat.
Key point: Energy transfer is unidirectional, and at each level, some energy is lost as heat
(Second Law of Thermodynamics).
PORTFOLIO
(COMPLETE ANSWERS)
2025 - DUE 2 October
2025
[Document subtitle]
[School]
[Course title]
, NST1502 Assignment 4 PORTFOLIO (COMPLETE ANSWERS) 2025 - DUE 2 October 2025
Course
Natural Science and Technology for classroom II (NST1502)
Institution
University Of South Africa (Unisa)
Book
New Natural Science and Technology
NST1502 Assignment 4 PORTFOLIO (COMPLETE ANSWERS) 2025 - DUE 2 October 2025 ; 100%
TRUSTED Complete, trusted solutions and explanations.
QUESTION 1 1.1 Define Kinetic energy. (2) 1.2 Explain how energy is transferred in an
ecosystem. (2) 1.3 What is the main purpose of photosynthesis in plants? (2) 1.4 What is cellular
respiration? (2) 1.5 Compare aerobic and anaerobic respiration. (4) 1.6 What is the role of ATP
in cellular processes? (2) 1.7 Explain how ATP is synthesized in the mitochondria. (3) 1.8 What
does ADP stand for? (1) 1.9 Explain the process of converting ADP to ATP. (2) 1.10 Insert a
screenshot to show your contributions to one of the engagements in the first unit. (Take this
from the discussion forum based on unit 1) (2) [22]
1.1 Define Kinetic energy. (2)
Kinetic energy is the energy possessed by an object due to its motion. It is directly proportional
to the mass of the object and the square of its velocity.
Formula: KE=12mv2KE = \frac{1}{2} m v^2KE=21mv2
Example: A moving car or a rolling ball has kinetic energy because it is in motion.
1.2 Explain how energy is transferred in an ecosystem. (2)
Energy flows in an ecosystem through food chains and food webs. Sunlight is captured by
producers (plants) through photosynthesis. Herbivores eat the plants, obtaining chemical
energy. Carnivores then eat herbivores, and energy is transferred along trophic levels.
Decomposers break down dead organisms, returning nutrients to the soil but not recovering all
energy, as some is lost as heat.
Key point: Energy transfer is unidirectional, and at each level, some energy is lost as heat
(Second Law of Thermodynamics).
