Unique Australia unit - Ecosystems

Question 1

What is an biotic factor?

Answer 1

An biotic factor includes all living things and their interactions with other organisms. Eg. A hungry dingo is an example of a biotic factor as it interacts with small mammals by eating them

Question 2

What are abiotic factors?

Answer 2

An abiotic factor is a non-living part of an environment that effects the way an organism lives. Eg, water, temperature, Ph levels, humidity

Question 3

Examples of Abiotic factors?

Answer 3

water, temperature, soil, sunlight, wind/air, minerals, humidity, pH

Question 4

Examples of biotic factors?

Answer 4

plants, trees, insects, animals, bacteria, fungi, protists

Question 5

Living things are grouped according to the way in which they get energy:

Answer 5

Producers (or autotrophs)
Consumers (or heterotrophs)

Question 6

What is a producer?

Answer 6

Producers are able to make their own food. Producers include green plants, they get their energy from the sun. A lot of the suns energy is lost by reflected light.

Question 7

What are consumers?

Answer 7

Consumers are organisms that eat plants or on other animals to obtain their energy.
Includes: animals and some bacteria.

Question 8

What are some consumer’s food?

Answer 8

Consumers obtain their energy from a variety of sources:
plant tissues (herbivores)
animal tissues (carnivores)
plant and animal tissues (omnivores)
dead plant or animal matter (detritivores and decomposers)

Question 9

What is a herbivore?

Answer 9

Animals that only eat plants. Eg koalas, kangaroos, wombats.

Question 10

what is a carnivore?

Answer 10

Animals that only eat other animals. Eg sharks, platypuses

Question 11

What is an omnivore?

Answer 11

Animals that eat plants and other animals. Eg. Emu, possum

Question 12

What is a decomposer?

Answer 12

organisms that break down dead things eg worms, slugs, bacteria

Question 13

what is a food chain?

Answer 13

Is a visual way of showing who eats what. The direction of the flow of energy in a food chain is shown in the direction of the arrow. Food chains usually consist of around 4/5/6 different organism.

Question 14

What are the trophics on a food chain?

Answer 14

Producer (Primary Producer) – convert energy from sun

First order (primary consumer) – herbivores that eat the plants

Second-order (secondary) consumer – carnivores that eat the herbivores

Tetitary consumer-eats the secondary consumer

Quaternary consumer- eats the tetitary consumer

Question 15

What is the Law of Conservation of Energy?

Answer 15

The Law of Conservation of Energy states that energy cannot be created or destroyed only changed from one form to another.

Question 16

How can a tree absorbing the sun’s energy be turned into another form?

Answer 16

Carbon dioxide and water combine together in the presence of light energy (sun) to produce glucose and oxygen for the producer. Glucose is food/energy for the organism and the oxygen that is produced allows us humans and other animals to breathe.

Question 17

why does each organism lose energy in the food chain?

Answer 17

Energy is lost as heat from each trophic level due to breathing and movement.

Question 18

What is the 10 percent rule in a food chain?

Answer 18

In Biology the general rule is that we assume that only 10% of the energy at each trophic level is transferred along the food chain.
This means that food chains can only be a few organisms long (generally 4 -6) as the top consumers would not receive enough energy if they were longer.

Question 19

population def?

Answer 19

A group of the same species in the same area.

Question 20

detrivore def?

Answer 20

Feed on dead or decaying remains and wastes. Eg worms, dung beetles

Question 21

autotroph def?

Answer 21

Another word for producers. They make their own food through for example photosynthesis. Eg. Plants, algae

Question 22

heterotroph def?

Answer 22

Is an organism that eats other plants or animals for energy and nutrients. Eg birds,

Question 23

(biological) succession def?

Answer 23

Succession is the change in either species composition, structure, or architecture of vegetation through time.

Question 24

what is an ecosystem?

Answer 24

An ecosystem is a system of organisms interacting with one another and the environment. An example of an ecosystem is the great barrier reef.

Question 25

habitat

Answer 25

where an organism lives

Question 26

first order consumer

Answer 26

Herbivores feed on the producers which are plants.

Question 27

second order consumer

Answer 27

Carnivores that feed on the first order consumer which is herbivores.

Question 28

predator

Answer 28

are the animals that eat other animals

Question 29

prey

Answer 29

are the animals eaten by predators.

Question 30

Earthworms are shown in the soil under the tree.

Answer 30

The earthworms are detritivores and are important as they help to break down decaying organism matter and turn it into nutrients that the plants can use. Their casts (or poop) unlocks nutrients like nitrogen and phosphorus. They also improve soil quality through aeration and are a source of food for predators.

Question 31

Explain why the food chain is represented as a pyramid.

Answer 31

Ecological pyramids are constructed by stacking boxes that represent trophic levels within a particular ecosystem. The size of the box indicates the number or amount of the feature being considered.

Question 32

Explain whether or not energy is lost along a food chain.

Answer 32

About 10% of energy is transferred along food chains from one trophic level to the next. The amount of available energy decreases from one trophic level to the next because:
○ it is used as heat energy
○ it is used for life processes (eg movement)
○ faeces and remains are passed to decomposers
Less energy is transferred at each level of the food chain so the biomass gets smaller.

As a result, there are usually fewer than five trophic levels in food chains.

Question 33

5. Explain why the number of top-order predators will always be small in any stable ecosystem.

Answer 33

Predators are fewer in number than prey because they are higher up the food chain. In a food chain, an organism passes on only part of the energy it receives from food. With less energy, each level in a food chain supports fewer individuals than the one below it.

Question 34

What is an energy pyramid?

Answer 34

It shows the amount of energy lost in each trophic level on the pyramid.

Question 35

What is a biomass pyramid?

Answer 35

The total amount of living tissue within a trophic level i called biomass.

Question 36

Pyramids of numbers?

Answer 36

The number of individual organisms at each trophic level.

Question 37

what is the word equation for photosynthesis?

Answer 37

carbon dioxide + water ->(In precense with sunlight and chlorophyll)glucose + oxygen

Question 38

write the balanced equation for photosynthesis

Answer 38

6CO2 + H2O ->C6H12O6 ->602

Question 39

explain the relevance of the terms respiration and combustion to the carbon cycle?

Answer 39

both cellular respiration and combustion involve the reaction of fuel and oxygen to produce heat/ water vapor and carbon dioxide into the atmosphere.

Question 40

how have human activities impacted Australian ecosystems?

Answer 40

loss of habitat for urban growth, and agriculture.
Introduced species in an ecosystem as the species can be predators of native wildlife. They can also impact vegetation.
construction of damns

Question 41

what is the effect of bushfires on an Australian ecosystem?

Answer 41

destroy adult trees allowing new trees to germinate
shelters destroyed so the animal population could decrease
young plants to receive sunglight

Question 42

what is the effect of flooding on an Australian ecosystem?

Answer 42

food shortages for animals
fast flooding causes a higher death toll for animals
they can help spread the organic matter, nutrients, and soils that enrich food plains.

Question 43

what is the effect of a drought on an ecosystem?

Answer 43

less food source for animals so populations decrease
soil and water quality diminishes