Crabs, earthworms, mitescqfbvth-4o w9-4e u,m and snails feed on the remains of dead plants and animals. What tybemwv4 9-4 tqo-,ucfhpe of organisms are these?

  Which of the following is not a sau7 u)repqp( 2sprotroph?

  Some fungi obtain nutrients t2zftue0zy c 8xeck)4+ kb0(yby releasing digestive enzymes into their surroundings. The enzymes break down things such as dead and decaying leaves and the fungi then absorb the products. Which of these terms best describes thesxc0+cbyfu24z)e0k8ye ( t tkze fungi?

  The illustration shows a rbdze/0 dumm:fh , d/0mice cultivation system that eliminates the need for fertilizers, herbicides and pesticides by using ducks in the organic cultivation of rice. In addition, Azolla, an aquatic floating fern, is grown on these fields because it harbours blue-green algae which can fix atmospheric nitrogen. Using this system, rice, ducks, and fish can all be produced mf:/h/dd,uz 0 ebm0d mfor human consumption in one location.

  Identify the row in the 35k0ng spw(q +9p3nx mcnkasftgg re0e3-/5mtable which gives the correct information about the different types of organisms. s0 tkngc -350gnk3n(exgr9aq5 s pe+/f3wmm p

  A student set up an aquatic mesocosoy6 o9wi5ow0ynw bioin1k w* 9x 2pkkq*v((u 5m using a commercially available seawater-filled glass orb, which included algae, shrimp, some corals and gravel. The student placed it near a win5 xw2boqy vki 6ow **ww9i i1o 5uyk(non09pk(dow to provide a light source. Which of the following statements are true?
I. The algae are autotrophs, produce carbon compounds and provide oxygen for organisms in the mesocosm
II. Saprotrophs present in the water and gravel help to recycle nutrients found in dead organisms
III. Herbivores usually present in a natural ecosystem can be excluded in the mesocosm

  Which of the following is/are true fji juk41)dnlybyzmjp 651)w 5xl: fz*9uk yo-or holozoic nutrition?
I. Demonstrated by saprotrophs
II. Involves complete or partial ingestion
III. Food is digested internally

  Which term refers to organisms that are both autotroi hojax2n,mgd2mx3/ t,+ /vt ophic and heterotrophic?

  What are incisors used kr uao4av3 4(u3rvph0 for?

The image below represents the skull of a gorilla, chid-i.z:/ +fo7lmsukw ip:c3emmpanzee, and human.

1.1.Outline the roles of different types of teeth.

1.2.Gorillas are primarily herbivorous but have large canines. Suggest a reason why.

1.3.Compare and contrast the teeth of a carnivore with a herbivore.

2.In terms of diet, distinguish between a folivore and a frugivore.

  Chytrids are unicellular organisms 7-n c ke2qe xr3-d;njjpeew. -that feed on pollen through extracellular secretion of digestive enzymes and absorption of the breakdown products. Which statement describes the nutritional mode of ;j en--en- . jq pkee32wd7rxcthis organism?

  Zooxanthellae are algae that live inside coral. Corals feed on the carbon compoxk1 s6cbh -ozdzk02,aunds produced by zooxanthellae from c-hk6,z b0x 1ackdo 2szarbon dioxide, water, and sunlight. Which describes the nutrition of these organisms?

  A student wants to set up an aquatic mesocosm using seawater to simuyivp5- et 6(nglate conditions in the food web (shown in the image below) and test its stability. He used seawater and sand from the area to set 6ypg5e( itnv -up the system and added some small organisms to the mesocosm.


1.In the food web shown, identify an autotroph ,which is   .

2.State a reason why phytoplankton shown in the food web would be a good addition to the mesocosm.

3.Discuss how saprotrophs perform a necessary function for the mesocosm.

4.Describe the disadvantages of using mesocosms in scientific investigations.

1. A student had a smal+ wvo 7)0dubdil pond in the backyard and wanted to add some fish. The fish would be predatvu 7i+b wod0d)ors of the pond and feed on the zooplankton (prey) growing in the pond. Zooplankton are small floating or weakly swimming organisms that are dependent on the phytoplankton or algae for their supply of nutrition.

She wanted to first determine whether Fish A or Fish B would be more suitable, or if both fish could be added to the pond. As a trial, she set up four mesocosms using water from the pond. She monitored the mesocosms and then added the fish to three of the mesocosms as shown. She took samples of water from the different mesocosms and tested it for chlorophyll content at a research lab nearby.


1.Outline why the mesocosms used would be considered a ‘closed system’.

2.Describe why adding mud or soil to the mesocosms would be advantageous.

3.Outline the reason for including ‘Mesocosm A’ with the experiment.

4.Explain the reason for monitoring chlorophyll content to analyze the effects of the fish as a predator.

5.State another variable that could be monitored to see the effect of adding fish to the mesocosms.

The following table shows the results obtained for chlorophyll (μg dm$^{-3}$) with the different additions of fish.

6.From the results obtained, suggest why the student decided to add both fish A and fish B to the pond.

1.Describe the process by which detritivores and uo2x-jtn o;g1saprotrophs obtain nutrition.

2.Describe how a quadrat can be used to estimate the population of poppies in a field.

3.Energy and nutrients move through ecosystems differently. Describe how energy and nutrients move through terrestrial ecosystems.

1.Outline the differences between mixotrophic an)ebwe5tdi)u pq . qce2mtv gza6ep)1 (p71nd3d holozoic nutrition.

2.Describe how herbivores are adapted to eating plants.

3.Explain the differences between obligate anaerobes, facultative anaerobes and obligate aerobes.