Chapter 19 Ecosystem

Question 1

According to the graph of predation, answer the following question

Deduce the relationship between preys and predators.

*___________ (name the relationship)

*________ larger than ________

*___________ delays_______

*______ is the food supply of ____

Answer 1

Predation.
1. Peak number of the prey is larger than that of predator
2. the changes of preadtors delay/ lag behind the preys

–> indicates that prey is the food supply of the predators.

Question 2

Explain the graph of competition.

*Beginning: the number of both species _______

Reason: they consume the ________

Answer 2

Beginning: the number of both species increase as they consu,e the same type of food.

Question 3

Explain the graph of competition.

*Result: the number of an species _____ while another species ________

*A species ______ another species and ________

*Another species ________

Answer 3

The number of an species increase while another species drops drastically

A species outcompetes another species and dominate the resources in the habitat

Another species starves to die due to insufficient food and energy supply and fail to meet their energy demand.

Question 4

Describe and explain the change in the population of predators and preys.

Beginning:
1.

Question 5

Deduce and explain the relationship between deer and bird.

*________________
*Birds can obtain _________ via the _______ movement of deer
*while the __________ are not affected

Answer 5

*Commensalism
*Birds can obtain food and energy from insects via the speedy movement of deer
*while the movement of dears are not affected

Question 6

Deduce the relationship between whales and bernides.

Answer 6

Parasitism

Question 8

State the change in symbiotic relationship between algae and coral reet bleaches after an oil leakage on the sea surface.

*From _______ to __________

Answer 8

Relationship between algae and coral reet bleaches changes from mutualism to competition.

Question 9

Explain why the symbolic relationship between algae and coral reet bleaches change from mutualism to competition after an oil leakage on the sea surface.

Before:

*Algae: absorbing ______ for carrying out _____to provide ______ and _______

• Coral: provide algae with ______

Answer 9

Algae absorb CO2 from coral for carrying out photosynthesis to provide oxygen and glucose for coral reef. While coral reef provides with shelter as protection.

Question 10

Explain why the symbolic relationship between algae and coral reet bleaches change from mutualism to competition after an oil leakage on the sea surface.

Change
* Oil leakage lead to reduced _______
*Algae tends to perform ________ rather than _____

*Coral reef will _______, resulting in its ______colour

Answer 10

Oil leakage leads to reduced light penetration. Algae tends to perform respiration rather than photosynthesis. Ultimately, to ensure the sufficient oxygen supply, coral reef will repel all algae, resulting in its white colour

Question 11

Fill in the missing information according to the process of primary succession.

*Primary succession starts with a ______ surface with the absence of ______ and

Answer 11

*Primary succession starts with a barren rock surface with the absence of soil layer and vegetation

Question 12

Fill in the missing information according to the process of primary succession.

*______ landed on the rock surface via wind

*____ decomposes _______ as soil and a soil layer was formed

Answer 12

Lichen landed on the rock surface via wind. Then fungi decomposes rock layer as soil and a soil layer was formed.

Question 13

Fill in the missing information according to the process of primary succession.

*

Question 14

According to the ecological pyramid, answer the following questions

How energy is lost in the ecosystem ?

• ________ to the surroundings via ______
• via energy trapped in the ____________ which cannot pass to the __________ in the upper tropical levels
• via ____________ in which energy is trapped in __________

*

Answer 14

• heat loss to the surroundings via respiration
• via energy trapped in the uneaten parts of organism which cannot pass to the consumers in the upper tropical levels
• via egestion and excretion in which energy is trapped in undigested waste

Question 15

Arrange the importance of the following factors in contributing to the energy loss in the ecosystem in ascending order.

Uneaten food, respiration, egestion and excretion

Answer 15

Egestion and excretion < uneaten food < respiration

Question 16

Explain why a eagle consume many spiders in order to survive

• eagle located at __________________ than spider
• As a ________, it has _____________ than the prey
• they must consume ________ prey’s to obtain enough energy to fulfil their energy requirements and compensate for ______________________

Answer 16

• eagle located at a higher tropical level than spider
• As a consumer, it has a larger biomass than the prey
• they must consume multiple prey’s to obtain enough energy to fulfil their energy requirements and compensate for the smaller sizes and biomass of the prey

Question 17

Fill in the blanks according to the statement below

Producers are _________ which carry out________ and form its own food (tree/ plants/ a_____/ p_________ b_____)

Answer 17

Producers are autothphytes
which carry out photosynthesis and form its own food (tree/ plants/ algae/ photosynthetic bacteria)

Question 18

When do secondary successions occur ?
After ______________ in order to ________ the biological community

Answer 18

After a major disturbance to the habitat such as wildfires/ any natural disaster in order to restore the biological community.

Question 19

What is the ecological niche of primary consumers ?

Answer 19

Herbivores (organisms that only eat plants)

Question 20

What is the ecological niche of secondary consumers ?

Answer 20

Carnivores (animals that only eat meat)

Question 21

What is the ecological niche of top consumers ?

Answer 21

Omnivores (animals obtain both plants and meat)

Question 22

Name two types of decomposers within the ecosystem

Answer 22

Fungi, putrefying bacteria

Question 23

Explain the shape of the inverted shape of pyramid of numbers

• The producer, tree, is _________________
• An individual organism, as an _______ in the _______tropical level is capable of __________ of ________ consumers in the higher tropical level.

Answer 23

• The producer, tree, is large in biomass
• An individual organism, as an producer in the lower tropical level is capable of supporting and satsifying the energy requirements of multiple consumers in the upper tropical level.

Question 24

Explain why the number of organisms keep decreasing when going up the pyramid.

• _______ is lost from each tropical level via _________
• A consumer need to _________ in the lower tropical level to satisfy and _______________

Answer 24

• energy is lost from each tropical level via heat loss to surronding by respiration.
• A consumer need to consume multiple species in the lower tropical level to satisfy and compensate for its energy requirements.

Question 25

How to obtain the drymass of an organism. * put the organism into ___ and heat it to ____ * repeat the above steps until a ______ is measured

Answer 25

* put the organism into an oven and heat it to 100 C * repeat the above steps until a constant mass is measured

Question 26

How do plants obtain carbon atoms from the atmosphere * plants perform photosynthesis by absorbing carbon dioxide in the atmosphere *There is a net uptake of carbon atoms from carbon dioxide for the formation of organic matter, which are carbon atoms in glucose molecules

Answer 26

* plants perform photosynthesis by absorbing carbon dioxide in the atmosphere *There is a net uptake of carbon atoms from carbon dioxide for the formation of organic matter, which are carbon atoms in glucose molecules

Question 28

How are carbon atoms released back to the atmosphere ?

Answer 28

*plants oxidizes glucose molecules via carrying out respiration *Otganic carbon atoms are released to the atmosphere as inorganic catbon atoms (Co2)

Question 30

Below is a description of the nitrogen cycle, fill in the blanks with suitable answers. In nitrogen fixation,_______ is converted as __________ by nitrogen fixing bacteria living in the root ________ of __________. The term "fixation" refers to the conversion from__________ in plants.

Answer 30

In nitrogen fixation, ntrogen gas in the air is converted as ammonium compound by nitrogen fixing bacteria living in the root nodules of leguminous plants. The term "fixation" refers to the conversion from gases to stored substances in plants.

Question 31

Below is a description of the nitrogen cycle, fill in the blanks with suitable answers. Nitrification takes place in __________ with ________ supply of oxygen Denitrification takes place in ____________ with _________ supply of oxygen. For instance, after a heavy rainfall in which ________

Answer 31

Nitrification takes place in aerobic environment with sufficient supply of oxygen Denitrification takes place in anaerobic environment with insufficient supply of oxygen. For instance, after a heavy rainfall in which the soil layer is waterlogged.

Question 32

Describe the process of nitrate assimilation by plants. Nitrates are taken up by plants via ___________ Plant cells combines ________and nitrates to form _________ ___________are joined together to form a _________ polypeptide _________ then __________ while some polypeptide chain _______ together to form a _____molecule with______________.

Answer 32

Nitrates are taken up by plants via active transport and diffusion Plant cells combines glucose and nitrates to form amino acid. amino acids are joined together to form a polypeptide polypeptide chain then coil/ fold up while some polypeptide chain bind together to form a 3D molecule with special confromation.

Question 33

Below is a description of the nitrogen cycle, fill in the blanks with suitable answers. State the advantage of using inorganic fertilizer over organic fertilizers. *It can be easily dissolved in the soil layer and absorbed by the plants *harvest can be boosted in a relatively short period of time.

Question 34

Below is a description of the nitrogen cycle, fill in the blanks with suitable answers. State the advanatge of using organic fertilizer over inorganic fertilizer. *It takes a long time for organic fertilizer to be completely dissolved as decomposers need time for decomposing solid waste into ammonium compound. *we can use excess amount of organic fertilizer without causing anaerobic reaction in plants.

Question 35

Below is a description of the nitrogen cycle, fill in the blanks with suitable answers.