Welcome to your Grade 8 General science chapter 5
After carefully reading the following 30 questions, choose the correct answer.
1.
Which organisms can produce their own food by releasing energy from simple chemical reactions?
2.
What is the graphical representation of the energy found within trophic levels called?
3.
Why can energy in an ecosystem NOT be recycled?
4.
Which organisms are always found at the end of each food chain?
5.
What is the term for a complex feeding interrelation consisting of many food chains?
6.
What is any naturally occurring substance on earth that humans use called?
7.
What is the cyclic movement of elements like carbon and nitrogen from the environment to organisms and back called?
8.
Which of the following is a non-living or physical component of an ecosystem?
9.
What is the main source of energy for most ecosystems?
10.
Biological interaction between members of the same species is called?
11.
What is the wise use of natural resources to ensure their availability for the future?
12.
Which soil property refers to the size distribution of mineral particles?
13.
What is the process of growing trees to restore or create forest areas?
14.
In a food chain, what role do green plants play?
15.
What is the transfer of nutrients and energy in a direct and simple system called?
16.
Which element is essential for metabolic and biological processes in living organisms?
17.
What describes a diagram used to express the amount of organisms in each trophic level?
18.
Which term refers to non-renewable natural resources?
19.
What is the primary cause of energy loss between trophic levels?
20.
Which process returns nitrogen gas to the atmosphere?
21.
What happens to the number of organisms in each group as you move from bottom to top of a trophic pyramid?
22.
What is the contamination of soil with harmful substances called?
23.
Which organisms are primary consumers in a food chain?
24.
What is the role of photosynthesis in an ecosystem?
25.
Which natural resource is considered renewable?
26.
What is the effect of deforestation on soil?
27.
Which trophic level has the most available energy?
28.
What is the process by which bacteria convert atmospheric nitrogen into ammonia?
29.
Which factor determines the suitability of soil for plant growth?
30.
Why are decomposers essential for nutrient cycling?
