Full transcript
0:00Thank you again Cecilia. Thank you
0:01colleagues. Good afternoon to you all.
0:05I'm Ma Bangu from team. I'm going to be
0:08presenting the framework the tips for
0:11the grade 10 test that is going to be
0:13written on the 16th of September 2026
0:17with the two topics the history of life
0:20on earth and the biosphere to the
0:22ecosystem.
0:24So uh now I'm starting with the
0:28presentation here. The first slide there
0:30um uh you have to remind your learners
0:35how to
0:37prepare for answering scientific
0:40investigation questions. So uh the most
0:44important thing that that your learners
0:45must do is to read the aim with
0:48understanding with comprehension. So
0:50from the aim they must be able to
0:53identify the independent and the
0:54dependent variables. So I made a an
0:58example there with one of the
0:59experiments. Grade 10 learners
1:01investigated the effect of the amount of
1:05humorous content on the growth of
1:07plants. So when you look at that aim
1:10colleagues
1:12or okay that uh the aim of the
1:14investigation there is uh to investigate
1:17the effect of the amount of humorous
1:19content on the growth of plants. So
1:22learners if this was um the
1:25investigation that we are going to write
1:27about on the 16th the independent
1:29variable will be the amount of humor
1:31content. So let's go and emphasize to
1:34our grade 10 learners because they most
1:36most of them are getting this wrong they
1:38include the effect. So when they are
1:41asked the independent variable they they
1:43they always say the effect of the amount
1:46of humorous content. So they must leave
1:48the effect out and only write the amount
1:50of humus content and the dependent
1:53variable which variable depends on the
1:55amount of hum content. It is uh the
1:58growth of length. So that is how they
2:02identify the the variables and here I
2:05made a short procedure there so that we
2:08can identify the um the the reliability
2:12and validity. So I said they used 10
2:16plants. Those 10 plants were 15 cm each.
2:20The plants were left to grow for 15 days
2:22and all plants were of the same species.
2:25So uh when we move on okay before I move
2:28on when reading the procedure colleagues
2:31with our learners we we we must make
2:34sure that uh when after reading every
2:37sentence they identify what is in that
2:39sentence. So like um the first sentence
2:42or the first part of the procedure says
2:4410 plans. So learners must know that
2:47when we are talking about the number of
2:48plans there it's reliability they can
2:51write are uh on top of that 10 plans and
2:54then they move on 15 cm each it means
2:57they were of all of the same size. So
2:59they can write V um above that 15 cm
3:04meaning that will be the answer when
3:07they are asked for validity and the the
3:10plants were left to grow for 15 days
3:12that can be taken as a long duration. So
3:16they can also write R there and uh also
3:19V there because the plants were left to
3:21grow for the same number of days which
3:23are 15 days and then all plants were of
3:26the same species. So they can write V
3:30there because that is validity. Same
3:33species everything everything they
3:35reading the procedure from grade 10 to
3:3612 they must write it before they even
3:39go to the question so that it becomes
3:41easy for them to come and uh take those
3:43answers when they they were they asked
3:46about them. And then
3:49uh here uh the first part in the table
3:52there uh that is the reliability. So uh
3:56when they they they are asked about the
3:59reliability. I said uh above 10 plans
4:02they will write reliability. So
4:04reliability colleagues can be asked in
4:06two ways. So the first the first way is
4:10how was reliability ensured. It means
4:13that is the past tense. Reliability was
4:15already ensured and that is the the
4:18answers are already there on the on the
4:20procedure. So it was ensured by using 10
4:24plans. We take 10 plants as a large
4:26sample size and then plants were left to
4:28grow for 15 days that would be taken as
4:31a long duration.
4:33The second way in which a reliability
4:35can be asked uh they can say how could
4:39they ensure reliability.
4:42So that is the future in future how how
4:45could this grade 10 learners ensure
4:46reliability. So they can use more than
4:4910 plants meaning that now we are taking
4:5210 plants as a small sample size because
4:54in future we want to see how reliable
4:57the experiment is by using more a larger
5:00sample size than the one we used before
5:03and they must u plants must be left to
5:07grow for more than 15 days. So if we or
5:10maybe they can say plants can be left to
5:12grow for for 20 days any number of days
5:16longer than the 15 days. So this is how
5:19we are answering reliability colleagues.
5:22Uh so let's go and emphasize it to our
5:25learners. No more uh um a large sample
5:29size. Increase the sample size increase.
5:31So the numbers if the numbers are there
5:33on the procedure they must be there on
5:35the answer on the answers. So when we
5:38move on to validity all plants were of
5:41the same species. So in this instance
5:44the the name of the species was not
5:46mentioned but if the name of the species
5:48is mentioned they will say all plants
5:50were of the same species and mention
5:52that name. And in the second answer
5:54there will be all plants were 15 cm
5:58they had the same length. So 15 cm must
6:00be there. You can uh learners cannot
6:03only say all plants were of the same
6:06length. That length must be mentioned.
6:09And then lastly, they were left to grow
6:12for the same duration which is 15 days.
6:15So that the 15 days but must be
6:17mentioned there colleagues. I hope you
6:20we are still together.
6:23Uh as we move on
6:26um the other thing is drawing up a
6:28conclusion. So when we draw a a a
6:31conclusion with our learners, let's
6:33ensure that they understand the aim. If
6:36they can understand the aim, it will be
6:38easy for them to draw up a conclusion.
6:40So in this in our case, we want uh they
6:43wanted to uh investigate the effect of
6:47the amount of humus content on uh blend
6:50growth. So with our conclusion, we must
6:53answer the aim. So our conclusion can be
6:57high humus content improves plant
6:59growth. So both our variables are there
7:01the humus content and the plant growth
7:04is there on the uh in in the answer. So
7:07one of them can say
7:15one of them can say
7:17sorry colleagues can
7:20can those learners please be muted. No.
7:23Oh,
7:27>> thank you. So, uh the other answer can
7:31be a low humus content um um resist
7:36plant growth or does not improve plant
7:38growth. So that that's what that's how
7:40they can they can answer but the the
7:43most important thing is that both the
7:44variables must be there in the uh
7:47conclusion answering the aim and then um
7:52the next part there is a drawing of
7:55graphs. I not draw any graph on the
7:57presentation here but we have to go and
8:01emphasize the criteria when we practice
8:03with our learners. learners will always
8:06get uh full six marks if they know where
8:09where do they get those marks. So we are
8:11going to emphasize where mark allocation
8:13is and um I made that abbreviation that
8:16we write on on the graph there T for
8:20type C for caption S for scale L for
8:24labels and P for blowing. So let's go
8:27and practice the graphs colleagues bar
8:30graph line graph and histogram. So those
8:33learners must
8:35uh we must make sure that our learners
8:36understand those criteria and they'll be
8:39able to get those marks. So if learners
8:42don't know that they get two marks for
8:44bloating, they can plot only two uh two
8:47bars if um our graph is a bar and leave
8:50other two bars thinking that they'll get
8:52full marks. So let's please emphasize
8:54with them the criteria for marking the
8:58graphs and when they draw the graphs
9:00surely they will remember where marks
9:02are located.
9:06Okay now we are getting into our first
9:09topic which is the history of life. The
9:12first um concept there is our geological
9:16time scale. So uh a geological time
9:20scale is the timeline that shows the
9:22events that took place through the
9:24history of life. That is the description
9:26of our geological time scale. This
9:29description can be there in our section
9:31A or it can be there in in our section B
9:34where learners are asked to describe a
9:36geological time scale or where they are
9:39given a description and they are asked
9:41to to give a biological term. And uh
9:47what must learners be able to do on the
9:49time scale? they must number one they
9:51must be able to identify the eon which
9:54are larger periods than the eras and um
9:58and then we'll be having the periods. So
10:02always they'll be given a geological
10:04time scale if it's there on the question
10:06paper and they'll they'll be asked maybe
10:08to identify the era or the period.
10:12Number two they can be asked to
10:14calculate the duration of an era or a
10:18period. So I made an an example there a
10:23duration uh if a question says calculate
10:26a the duration of a paleoic era. So let
10:30us will come to
10:33um our
10:36period there or our era here is our era
10:39the paleoic era and uh they they must
10:44okay sorry colleagues okay they'll come
10:46to paleoic era here and then the start
10:49of the paleozoic era was 542 million
10:53years and then it ended um at 251
10:59million years. So they'll say 542
11:02million years minus 251 million years
11:06and it gives them 291 million years. So
11:09it means the Paleozoic era lasted for
11:13200 291.
11:22>> Okay, thank you. It means the Paleozoic
11:25era lasted for 291 million years. We
11:29cannot say the paleoic era lasted for
11:32291 million years ago.
11:35We are saying it lasted for 291 million
11:38years. So that is why I said here the
11:41units can be in million years or million
11:43years ago. But if a question says when
11:46did the paleoic era start? So we will
11:50say it started 5 542
11:53million years ago. Then you can say
11:56millionaires ago in that instance and
11:59then um
12:02oh the second question was um when did
12:04the misoic era end? So when we we look
12:09here is our misoic era and then it
12:12started 251 million years ago and then
12:16it ended 65 million years ago. So
12:19they'll go with this line or where the
12:22misoic era ends and then this is where
12:24the misoic era started. So when the
12:28duration is asked they'll say 251us
12:3265 and then they'll get their answer.
12:36This is how uh we do some of the
12:38interpretation. And then number
12:42uh four because number three I already
12:45talked about is that of the millionaires
12:47the units and then if we must emphasize
12:50colleagues to our learners that they
12:52must ensure that always they write
12:55units. So if they can say 252us 251 is
12:59equals to 291. They'll only get a mark
13:02for calculation and no mark for the
13:05answer if the answer does not include
13:07units.
13:08Number four. Number four, learners can
13:11also be asked to identify the major
13:14events in each period. So when we come
13:16to our geological time scale, let's say
13:21uh a question asks
13:23name two major events that took place in
13:26misoic era. So they'll come to this part
13:29and say uh there was first flowering
13:31plants and dinosaurs were dominant. So
13:34that is uh uh those are the two events
13:38that took place during the misoid era.
13:40So when they they when they are asked
13:42about the cenosoidic era they'll say
13:45early homo sapiens evolved and then
13:48earliest homminates evolved the
13:50dominance of mammals. So they'll just
13:53come to their time scale and um take
13:57those major events as they are. If they
13:59asked two they'll write two. If they
14:01asked one they'll just write one.
14:04I hope we are still together colleagues.
14:08And then we are also still continuing
14:10with our geological times K. So um here
14:15the first point says each will show the
14:17timeline in million years ago like we we
14:21we saw there they also show the fossils
14:24found and events that took place. We saw
14:27that the divisions of the geological
14:29time scales are organized uh
14:32strategraphically
14:33according to the naturally occurring
14:36layers of rocks with the oldest and at
14:40the bottom and the youngest at the top.
14:42So that is our relative dating one of
14:44our methods of dating. So the fossil
14:46that is found on the lower levels it
14:48means it is older than the one on the
14:52upper layers of the rock. And then uh
14:55point number four, when reading the time
14:57scale, learners must always start at the
15:00bottom. We start at the bottom because
15:03that's where the older years are. And
15:05then we come to the present at the top
15:07there. And then we must note colleagues
15:10with our learners there that learners
15:13are not expected to memorize the names
15:15of the eons, the era of the periods. A
15:19geological time scale will always be
15:21given to our learners. So learners must
15:23make sure that they they know how to
15:26interpret the time scale, not memorize
15:28the paleo, the miso and all those
15:31because they can sometimes get the
15:33scaling wrong. So let's teach them how
15:36to interpret the time scale and um take
15:40out those use the use any example of the
15:43time scale calculate the durations
15:45calculate when the periods started and
15:47when they ended and name the periods and
15:50all those but they just interpret.
15:54Thank you.
15:55And then as we move on here we come to
15:58fossils. Uh the slide says definition of
16:00fossils, paleontology and
16:02paleontologist.
16:04So learners must be able to define what
16:07is a fossil. Fossils are remains of
16:12animals and plants that lived in the
16:15past. They are preserved in rocks. So
16:18that is the definition of a fossil. They
16:20must make sure that on the 16th they
16:22know this definition. And then
16:24paleontology
16:26the study of fossils and uh
16:29paleontologist that person who studies
16:32fossils. So these are the definitions
16:35learners can be asked to define and or
16:39they can be in section A in multiple
16:41choice biological terms or our matching
16:44columns.
16:46And then uh this this slide here focuses
16:50on fossilization the the process of
16:53fossil formation. So when we look in in
16:57uh into this figure here this figure
17:00says the dinosaur dies in a river. The
17:04body is covered with sediments and meat
17:07decomposes. The dinosaur becomes a a
17:10fossil. the sediments become uh become
17:14rocks
17:15and the skeleton is pressed
17:18and uh the earth's movement rise the
17:22layers of the rocks through the surface
17:24then the rock erodess exposing the
17:27fossils. So this is the summary in a
17:31picture format and then this is a
17:33summary of how uh fossils are formed in
17:37a paragraph format. So it says the plant
17:40dies or or animal dies and it is covered
17:44with sediments. The the soft tissue
17:47decomposed and um the hard parts such as
17:51bones and shells are preserved by the
17:53organic material being replaced by
17:56hardened uh hard and or hardened by
17:59minerals and then more sediment layers
18:03cover uh they cover it over hundreds of
18:07years. The sediments are hardened and
18:10forms sedimentary rocks. The fossils are
18:13trapped for millions of years. Then the
18:16sediment uh sedimentary rocks are pushed
18:19to the surface. Then the fossils will be
18:21exposed and found by paleontologist
18:25which are those people who study
18:26fossils. So let's make sure this uh
18:30paragraph is studied. Colleagues, this
18:32is uh NB here. Let's uh make sure that
18:36our learners are able to describe that
18:39paragraph of fossil formation. Then uh
18:42down there we are having two methods of
18:45dating fossils. So there's two methods
18:47of dating fossils. Let's make sure that
18:50our our learners know them. Relative
18:52dating and radiometric dating. So let's
18:56make sure those uh learners they know
18:59the description and the methods of
19:02dating. Let's remember this test is only
19:0550 marks. So this paragraph um will
19:09weigh a lot from that question paper.
19:12And then
19:14uh here I'm having important concepts to
19:17remember. Learners must remember these
19:20concepts. Um they must they must be able
19:24to differentiate between species and
19:26population. So let's go and teach our
19:29learners. Uh we I know we taught them.
19:31Let's go and remind them what are
19:34species and what is a population. So
19:38species
19:40organisms a group organisms which are
19:43characteristics they able to interbreed
19:46and they produce fertile offspring. So
19:47those three things must be there if a
19:49description is asked but they must know
19:52the description if a biological term
19:54species is asked. and the population a
19:58group of organisms the same species in
20:02same habitat at the certain time or yeah
20:05during a certain period. So those three
20:08things must be there either a population
20:10will be asked as a description or a
20:13population will be there in section a
20:14biological term and learners will be
20:16asked to say that is a population and a
20:20food web and a food chain.
20:23a food web learners they will be maybe
20:27will they will be given a food chain or
20:29they'll be given a food web or they'll
20:30be asked to draw a food web and um here
20:35we are here here we are still on the
20:37concept so they'll say food web inter
20:41food chains and in a food chain a
20:44diagram that shows the
20:47um energy traveling from one organism to
20:51to the other energy flow or energy flow
20:54from one organism to the other and then
20:56it will be the energy flow will be
20:58represented by arrows there. So if
21:00there's a food chain learners must be
21:02able to identify that this is a food
21:04chain and this organism is maybe a
21:08producer primary consumer and all those.
21:11So if there is a food web learners must
21:13be able to take out food a food chain
21:17out of a a complex food web and
21:22uh spheres we are having our four
21:25spheres there learners must know the
21:27atmosphere the sphere where they are
21:30gases lithosphere the sphere where we
21:33find our soil and rocks hydrosphere the
21:36sphere made up of water water bodies all
21:39water bodies on And then the biosphere,
21:42the sphere where we find life. Those
21:44descriptions must be known by our
21:46learners when we write on the 16th. And
21:48then the other concept is biogeography
21:52which is linked to grade 12. So here in
21:55biogeography they'll be saying the study
21:58of the distribution of um organ extinct
22:02and living organisms across the earth.
22:05So the study of the distribution bio is
22:09the study of living organisms geography.
22:12How are they distributed on earth? So
22:14let's go and emphasize this terminology.
22:17I know some of us colleagues in grade
22:1910, we are not teaching it to the
22:21latter. Let's go teach it because it is
22:24linked also to our grade 12 syllabus.
22:27And then mass extinction um when a large
22:31number of organisms die out within a
22:34short period of time. Let's go and teach
22:36our learners. If learners are listening
22:38now, please learners go and uh know the
22:41all of these concepts will be able to
22:43pass this test. Thank you.
22:48And then um as we move on, we are now on
22:53soil types. Yes. and uh their edafic
22:56factors. So here we are having sand
23:00soil, loom soil and clay soil. So the
23:03adafic factor can be the size of the
23:06particle, the water holding capacity or
23:09some of us are saying water retention
23:11and then the humus content and the
23:13amount of air the air spaces between
23:16those particles. So sand has the largest
23:19particles
23:21and loom is a mixture of sand and clay
23:24and clay has the smallest particles. And
23:27then um when coming to water holding
23:30capacity, sand has the low water holding
23:32capacity. It means it drains quickly.
23:35When you pour water on sand soil, uh
23:38there'll be a um a larger volume of
23:42filtrate than all the two types of soil.
23:45And then loom has a good water holding
23:48capacity. It means it has a ideal
23:50balance of holding water. Some of the
23:53water will pass through but some will be
23:55kept. That is why we said loom soil when
23:58teaching our learners that loom soil is
24:01one of the best soil for agricultural
24:04purposes where we can plant our plants.
24:07And then clay soil has high water
24:11retention. It retains water and can be
24:14water locked. Let's remind our learners
24:16that lol can be water locked because it
24:19retains high um amount of water and the
24:24humus content in sand. Low low humus
24:28content. It means um it it adds on those
24:31characteristics that we cannot plant on
24:33we cannot plant our plants on sand soil.
24:37And loom soil is has high humus content.
24:41means that the soil is fertile and rich
24:44for planting and then clay moderate to
24:47high. Some of the clay soils have high
24:50humus content. Therefore, but you cannot
24:52plant on clay because of this um high
24:57water retention which can make it water
24:59locked and the amount of air high amount
25:02of air large air spaces. That's why we
25:05said when you pour water on sand soil,
25:08it will drain h quickly. And then um
25:12loom soil has moderate to high uh air
25:17content but um all the characteristics
25:20makes it h very suitable for blending.
25:25And then clay soil has no amount of air.
25:30That also adds to why it can be water
25:33locked. low um amount of air and retains
25:37more water. So we cannot plant on clay
25:40soil because of that but we can plant on
25:44loom soil. Those are edafic factors.
25:46When they ask about edafic factors they
25:49are the characteristics of different
25:51types of soil. These characteristics
25:53here all of them are edafic factors. So
25:56here are the characteristics. learners
25:58must know those characteristics
26:01especially the water holding capacity
26:04here. So uh the water holding capacity
26:07is of the most important of this um
26:11factors
26:13and then we move on to our water cycle.
26:18The water cycle focuses on um the
26:22different
26:24uh processes that takes place. H here we
26:27are having evaporation whereby water in
26:30the form of vapor escapes to um the sky
26:34there and then we are having
26:35condensation. Condensation which is the
26:38formation of clouds the formation of
26:41clouds. So let's make sure that our
26:43learners know this uh process uh
26:47condensation there and the forms of
26:49precipitation. learners can know. Let's
26:52make sure that they know those forms of
26:54precipitation, the rain and um few
26:57others, rain, hail, snow and all those.
27:00So, uh there's no much on the water
27:03cycle, but let's go and emphasize the
27:07processes for future purposes, but for
27:10this test, let's make sure that they can
27:13only describe the the processes.
27:17Uh as we move on we also have the
27:19nitrogen cycle. the nitrogen cycle. Um
27:23we are having processes where the
27:26process whereby nitrogen is fixed here
27:29we are having nitrogen gas in the
27:31atmosphere and because of lightning
27:35nitrogen can be fixed and be nitrates in
27:39the in the soil also because of nitrogen
27:43fixing bacteria or nitrifying bacteria
27:46and then nitrogen can be nitrates in the
27:49soil. So let's make sure that uh that
27:52type of bacteria is known by our
27:54learners. Nitrifying bacteria. The
27:56process is um nitrification.
27:59Here is uh the process nitrifying
28:02bacteria to convert nitrogen gas into
28:05nitrates in the soil. So the process is
28:08nitrification. It is done by the
28:11nitrifying bacteria and the um when
28:15nitrogen
28:17uh al also by nitrogen can also be
28:20converted nitrogen gas can be converted
28:23by lightening into those nitrates in the
28:27in the soil. So let's go and emphasize
28:30uh the process nitrification,
28:32denitrification
28:34and um nitrifying bacteria and
28:37denitrifying bacteria. No uh there will
28:41be no process um as shown here but those
28:46um
28:47uh processes there will be no larger a
28:50larger cycle like this one but the
28:52processes are there on the paper. they
28:54are definitely there
28:56and
28:58here
29:00uh are different roles of different
29:02components in a food chain. So
29:05we are having producers organisms that
29:09make their own uh food through
29:11photosynthesis. These are our plants. So
29:13learners must know uh that producers are
29:18plants. If there's a plant on on the
29:20food chain and they are asked to
29:22identify a producer, they'll choose that
29:24blend, they cannot if a plant is given a
29:27name like maze, they must write maze
29:30like it says. And then the primary
29:32consumer those he feed they feed
29:36directly on our producers. They feed on
29:40plants or algae and secondary consumers.
29:44Secondary consumers will feed on primary
29:46consumers. They can be carnivores.
29:50Carnivores it means they eat meat only.
29:53They eat those plants that eat meat
29:56only. So let's make sure that our
29:58learners uh know those
30:02concepts. They can also even identify
30:04the secondary consumers on our food
30:07chain if it is given or our food web.
30:10And then the tertiary consumers it means
30:13they are the fourth on the trophic level
30:15and they'll feed on secondary consumers.
30:18They can they can also be carnivoros or
30:21omnivores. So sorry I forgot the
30:23omnivores here. So omnivores feed both
30:26on meat and plants. So also the the
30:30tertiary consumers can be carnivores or
30:32omnivores. So they feed directly on
30:35secondary consumers. And then we'll be
30:38having our decomposers.
30:40Decomposers are those organisms that
30:44break down dead organic matter and waste
30:48products
30:49from all other trophic levels. They they
30:52are not just coming after tertiary
30:54consumers. They break even dead plants,
30:57dead primary consumers, dead secondary
31:00consumers and dead tertiary consumers.
31:03They are our decomposers. So an example
31:05of a decomposer can be uh bacteria and
31:09fungi. And we have saproides.
31:13Saprophitic organisms are those that
31:16feed on dead organic matter. They feed
31:19on dead organic matter only. They wait
31:22for an organism to die and then they
31:24come and feed on that organism. So let's
31:27let's go
31:29uh and emphasize this concepts to our
31:33learners or this components of a food
31:35chain to our learners. If they are given
31:37a food chain, they'll be they must be
31:39able to identify this components. And
31:42then if they given also a food web, let
31:45them be able even if this concepts are
31:48there on uh section A, they must be able
31:52to answer. If a question says organisms
31:56that make their own food through
31:57photosynthesis, they can say producers.
32:00So let's go and emphasize it. And then
32:04uh the food chains are continuing there.
32:08So the food chains are diagrams that
32:10show the flow of energy from one
32:12organism to the other like I said
32:14earlier. So here's an example of a food
32:16chain. Uh the the arrows there shows the
32:19transfer of energy. So we are having a
32:22plant here. This is our producer, a
32:24grasshopper primary consumer, a frog the
32:27secondary consumer and a snake which is
32:30our tertiary consumer.
32:33So um learners can be asked identify the
32:36primary consumer they'll say a blend no
32:40a producer that is our blend a primary
32:42consumer a grasshopper a secondary
32:44consumer a frog and a tertiary consumer
32:47a snake and then one of the important
32:50questions that learners must be able to
32:52answer on the 16th uh will be what will
32:56happen to the number of plants and frogs
33:00if the grasshopper die out it. This is
33:03an example. This is not a the question
33:06as it is on the question paper. But this
33:08is how uh the question will be slightly
33:12phrased. So in our uh food chain here uh
33:18they are saying what will happen to the
33:20number of plants here are our plants and
33:23frogs. Here are our frogs. If all the
33:26grasshoppers die out. Or if all these
33:28grasshoppers die out, what will happen
33:30to the number the number of this? So
33:34when looking at this food chain, the
33:36grasshopper feeds on the plants. So if
33:40there are no more grasshoppers in this
33:42ecosystem, it means the number of plants
33:45will increase. These plants will
33:47increase. And then if uh because the the
33:51frog which is the the secondary consumer
33:53feeds on the grasshopper it means when
33:56all the grasshoppers die it means uh the
33:59the frog will not have anything to feed
34:02on. It means the number and as a result
34:05the the frogs will die. Therefore the
34:08number of frogs will decrease. So this
34:11is an example of how uh learners would
34:15be expected to interpret a a food chain.
34:19So the number of uh frogs will decrease
34:22and the number of plants will increase.
34:24But if they say describe if a question
34:27says describe what will happen describe
34:30what will happen to the number or
34:32explain yeah explain what will happen to
34:34the number they they'll have to say the
34:36number of plants will increase because
34:40the grasshoass which feeds on um or
34:44there will be no more grassopass feeding
34:46on plants and the number of frogs will
34:49decrease because they will have nothing
34:51to eat or they'll have no food to eat.
34:55So that is describing why are they
34:57dying? Why is the number decreasing? So
35:00we are not talking we are not saying
35:01anything about the the snake because the
35:04question was straightforward talking
35:06about frogs and plants.
35:09I hope we are together there colleagues
35:11and learners who are watching. And then
35:15when we move on with our presentation we
35:18come to the plant adaptation to water.
35:21This is uh some of uh the topics there
35:24in our biosphere to ecosystem. So here
35:29we are having the plant types. We are
35:31having zeropites and then we are having
35:34mopides and hydrophes. So the zeropites
35:38are those that live or survive in dry
35:41regions and they are characteristics.
35:44They have a thick cuticle. I know
35:46learners like the cuticle. So let's go
35:48back again and emphasize that the
35:50cuticle will be thick to prevent water
35:53loss in the zero five and then the xylem
35:56will be present to transport water.
35:59They'll have thick fleshy leaves to
36:02store water and then they'll have few
36:05stomatal pores few stomatal pores so
36:07that they can lose as little water as
36:09they can and those stomatal ples will be
36:12on the lower surface of the leaves
36:15because if the stomatal pores are on the
36:17upper surface of the leaf more water
36:19will be lost and then here we are having
36:22our messy. The meopyes grow in moderate
36:25water conditions. So their
36:27characteristics are a mixture of
36:29zeropides and hydrophes. The
36:31hydrophilites hydro from the word water.
36:35So this ones live in water. Uh this one
36:39live in water. So let's make sure that
36:43we go and emphasize those uh
36:45characteristics of hydrophilites
36:49and mostly characteristics of uh
36:53zeropes. learners can be asked to
36:56mention the characteristics of zeropites
36:58or maybe to differentiate between
37:00zeropides and hydrophilites.
37:04So in hydrophilites there's no cuticle
37:07because this plant now is already in
37:08water. Um uh it does not worry about
37:12losing a large amount of water and
37:14there's no xyllem for water trans
37:17transportation because it lives directly
37:19in water. The leaves are large are large
37:21and flat. But the leaves of hydrophes or
37:25sorry of zeropites are thick and fleshy.
37:28So they are thick and fleshy to store
37:30water. These ones are large and flat.
37:32They don't need to to store water.
37:35Stomatal pores are on the upper surface
37:38of the leaves and uh there are also many
37:42stomatal pores on the upper surface of
37:43the leaf because the lower surface will
37:46be attached directly on the surface of
37:49water. So this plant um has tomato paw
37:53on the upper surface so that it can lose
37:56as much water as it can. So let's go
37:59colleagues and emphasize this different
38:02types of plants and how they adapted to
38:05water in their living conditions.
38:08Thank you. And
38:11um this was the last slide. Uh thank you
38:14very much.
38:18But sorry a bit colleagues. Can I please
38:21go back to this? I I think I
38:26to this
38:28So sorry um this slide of the types of
38:33soil. Let's go and emphasize uh again
38:36this water holding capacity or retention
38:39of water. Uh that sand soil drains water
38:44quickly and if it drains water quickly
38:47there will be large amount of
38:50um of uh filtrate. So if the maybe
38:54there's an experiment about this water
38:56holding capacity and there's a soil with
38:59a large volume of filtrate that will be
39:02sent and the volume with moderate amount
39:04of filtrate that will be loom soil and
39:07the uh the the soil with a lowest volume
39:11of filtrate that will be um our clay
39:14soil. So with the amount of filtrate in
39:18an experiment um we can be able to
39:21identify the types of soil and then we
39:23can be able to give those
39:25characteristic. Why um does uh soil A
39:29has this amount of filtrate if it's sand
39:33soil you will say it it has the large
39:35particles it drains very quickly because
39:38of large air spaces between the
39:40particles. So let's please go and
39:42emphasize that characteristic to our
39:47learners. Thank you very much. Thank you
39:49colleagues. Thank you Cecilia.