Name: ____________________________
Grade: _____________
Alien species, Wetlands and Scientific method
March 2021
Time: 50 minutes
Question 1:
Total: 45 marks
Match the scientific term in column A with the definition in column B
[6]
Zone 1
Zone 3
Answer
Column A
[
]
[
]
]
[
]
Column B
Zone 2 Wetland (pictured A. From a different country
above)
Indigenous
[
Zone 2
Hypothesis
B.
A list of the steps followed to perform an
experiment
C. A prediction about the end results
Zone 3 Wetland (pictured D. A list of utensils and chemicals used in an
above)
experiment
[
]
[
]
Variable
E. Temporarily wet
Apparatus
F.
Seasonally wet
G. The question that starts the investigation
H. Factors that can change in an investigation
I.
Naturally occurring in that country
1
Question 2:
You were picked as the class reperesentitive for the Enviro club. Your task was to investigate
a new wetland in the area, similar to the vlei on the St. Anne’s College property. Answer the
questions that follow:
2.1
If a flood happened to hit the new wetland, what effect would the wetland have on the
flood, and especially the damage caused by the flood?
(2)
_________________________________________________________________________
_________________________________________________________________________
_________________________________________________________________________
2.2
The Enviro club would like to bottle the water in the new wetland for drinking. They ask
you to determine if they should bottle the water entering the wetland, or the water
leaving the wetland. Based on your knowledge on wetlands, which option would you
suggest? Give a reason for your answer.
(3)
_________________________________________________________________________
_________________________________________________________________________
_________________________________________________________________________
_________________________________________________________________________
2.3
Carly wants to introduce new plants to the wetland, but she knows that not all plants
are able grow in the anaerobic soil conditions found in wetlands. After doing some
research she finds three different types of plants that are able to grow in wetland soil.
She plants all three of these different plants in the wetland soil and leaves them for a
week to see which one grew the fastest. The results will allow her to decide which plant
would be best suited to this new wetland. Answer the following questions.
2.3.1 Identify the independent variable in this experiment.
(1)
___________________________________________________________________
2.3.2 Identify the dependent variable in this experiment.
(1)
___________________________________________________________________
2.3.3 Name two fixed variables in this experiment.
(2)
___________________________________________________________________
___________________________________________________________________
[9]
2
Question 3:
Rutendo is baking a chocolate cake for Mother’s Day. She asked her friend for a recipe, but
the recipe was hard to read, and she was unsure if she should add 10ml, 15ml or 20ml of
baking powder to her batter mix. Rutendo decides that she will bake a few chocolate cakes,
each with a different volume of baking powder, to see which volume of baking powder makes
her chocolate cake rise the highest. Answer the questions below:
3.1
Formulate a research question for her experiment.
(2)
___________________________________________________________________
___________________________________________________________________
3.2
Provide a suitable hypothesis for this experiment.
(2)
___________________________________________________________________
___________________________________________________________________
3.3
Identify the independent variable in this experiment.
(2)
___________________________________________________________________
3.4
Identify the dependent variable in this experiment.
(2)
___________________________________________________________________
3.5
Name two fixed variables that Rutendo would have to keep the same to ensure that
the experiment is fair and valid.
(2)
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
[10]
3
Question 4:
Mlibo is opening a bakery, and is trying out different toppings for her
delicious, vanilla cupcakes. She is concerned that the bakery will be
very busy and that she won’t have enough time to decorate all her
cupcakes during business hours. She conducts an experiment to see
which ingredient will melt the fastest, to ensure that she can easily melt
and drizzle it over her cupcakes to decorate them. She decides to melt
marshmallows, white chocolate, dark chocolate and toffees. The
marshmallows melted in 3 seconds, the white chocolate melted in 20 seconds, the dark
chocolate melted in 30 seconds and the toffees melted in 15 seconds. Answer the questions
that follow.
4.1 Provide a suitable aim for Mlibo’s experiment
(2)
_________________________________________________________________________
_________________________________________________________________________
4.2 Draw a table in the space provided below, to show the summarise Mlibo’s results (5)
4.3 Based on these results, which topping would be the most time efficient for Mlibo to use
when her bakery is very busy?_______________________________________
(1)
[8]
4
Question 5:
Hannah is planting a vegetable garden. She decides to start her garden by planting tomato
plants. She isn’t sure how much water she should give them for them to grow the tallest, so
she decides to conduct an experiment to find the best volume of water that she should be
giving them. She plants 3 tomato plants, and gives each of them a different volume of water
over 20 days. She measured them at the start and at the end of the 20 day period, and
calculated their total growth after 20 days. Her results are summarised in the table below:
Volume of water (litres)
Total growth after 20 days (cm)
2
20
3
35
5
50
5.1 Draw a graph based on the results of Hannah’s experiment (ON THE GRAPH PAPER
PROVIDED)
(7)
5.2 Based on the graph, describe the relationship between the volume of water given to the
plants and the total growth of the plants over 20 days.
(2)
_________________________________________________________________________
_________________________________________________________________________
5.3 Hannah notices that some alien plants are invading her garden. What are alien plants?
_________________________________________________________________________
____________________________________________________________________
(1)
5.4 In which two ways can Hannah act to get rid of these alien plants?
(2)
_____________________________________________________________________
_____________________________________________________________________
_____________________________________________________________________
_____________________________________________________________________
_____________________________________________________________________
_____________________________________________________________________
[12]
Total 45 marks
5
6