Review Question

1. Student’s Name: Sem Meng Eang
ID: #03058 (BA-22M)
Review Question Chap 5
4/ List five predators and their prey organisms.
 Predators and their prey organisms relationships include:
 A snake is a predator, and a chicken is its prey.
 Penguin and fish
 Lion and zebra
 Frogs and insects
 An eagle and a mouse
Predators help prey populations by eliminating the weak one.
5/ How is an ecosystem different from a community?
 A community is a group of populations living and interacting with each other in an area, an
environment is a community and its abiotic (non-living) environment.
 An ecosystemis defines space in which interaction take place between a community, with all its
complex interrelationships, and the physical environment. A community is an assemblage of all
the interacting populations of different species of organisms in an area.
6/ Humans raising cattle for food is what kind of relationship?
Humans raising cattle for food is a technically form of predation. Humans are secondary
consumers feeding on the cattle which are primary consumers feeding on the plants which are primary
producers. It could be argued however, that is a type of mutualistic relationship in which both population
benefit, because the cattle has been so changed that it cannot survive without human interaction.
7/ Give examples of organisms that are herbivores, carnivores, and omnivores.
Examples of herbivores are deer, rabbits, koalas, cows, human vegetarian.
Examples of carnivores are lions, tigers, wolves, sharks, crocodiles.
Examples of omnivores are humans, bears, and pigs.
8/ What are some different trophic levels in an ecosystem?
 (tropic level 1) Producers: Plants.
 (tropic level 2) Herbivores or primary consumer: Animals that eat plants.
 (tropic level 3) Carnivores or secondary consumer: Animals that eat animals.
 (tropic level 4) Carnivores: Carnivores that eat carnivores.
 Decomposers: can be at any level except level 1 (eat plants=tropic level 2, eat animal= tropic level
3). Example: Bacteria, Parasites, Scavengers.
Key Term
Biomass: Any accumulation of organic material produced by living things.
Carnivores: Animals that eat other animals.
Community: Interacting group of different species.
Competition: An interacting between two organisms in which both require the same limited resource,
which result in harm to both.
Decomposers: Small organisms, such as bacteria and fungi, that cause the decay of dead organic matter
and recycle nutrients.
Ecology: A branch of science that deals with the interrelationship between organisms and their
environment.
Ecosystem: A group of interacting species along with their physical environment.

2. Evolution: A change in the structure, behavior, or physiology of a population of organisms as a result of
some organisms with favorable characteristics having greater reproductive success than those organisms
with less favorable characteristics.
Herbivores: Primary consumers, animals that eat plants.
Niche: The total role an organism plays in its ecosystem.
Omnivores: Animals that eat both plants and other animals.
Parasite: an organism adapted to survival by using another living organism (host) for nourishment.
Predator: An animal that kills and eats another organism.
Symbiosis: A close, long-lasting physical relationship between members of two different species