ABLE EDUCATION CENTRE UNIT 7 LIVING THINGS AND AIR A
1 Multiple-choice questions
Some gas is bubbled into hydrogencarbonate indicator and the indicator turns from red to yellow. The gas can be A oxygen. B nitrogen. C hydrogen. D carbon dioxide. 2 Some gas is bubbled into lime water and the lime water remains clear. What is the conclusion? A The gas is oxygen. B The gas must not be carbon dioxide. C The gas must not be nitrogen. D The gas is hydrogen. 3 4 In the test for water, we use A cobalt chloride paper. B lime water. C hydrogencarbonate indicator. D iodine solution. If some oil in a cooking pan catches fire when cooking, we should (1) pour water to it to put out the fire. (2) cover the flames with a lid. (3) take the pan with the burning oil away from the stove. A (1) only B (2) only C (3) only D (1), (2) and (3) 5 The energy we need for all body activities comes from A the sun. B air. C food. D water. E6 With reference to the following food labels, which food contains the greatest amount of energy per serving? A B C D 7 In the test for starch, what is the reason of putting the leaf in hot alcohol? A To kill the germs on the leaf. B To remove water from the leaf. C To detect the presence of starch in the leaf. D To dissolve chlorophyll from the leaf. E8 What are structure X and Y in the following X-­‐ray film? Y
X
X A B C D Y rib diaphragm lung lung lung intercostal muscle diaphragm rib E9 What is the action of ribs when we breathe out? A They move upwards and outwards. B They move inwards and downwards. C They contract. D They relax. 10 Some plant cells are shown in the following diagram. What is the main function of structure X? X
A Photosynthesis B Storage of food C Gaseous exchange D Water evaporation 11 What are the major sources of air pollutants in Hong Kong? (1) Vehicles (2) Cigarette smoke (3) Construction sites (4) Factories in Pearl River Delta A (1) and (2) only B (2) and (4) only C (1), (3) and (4) only D (2), (3) and (4) only 12 The following setup can collect substances from cigarette smoke. After a short period of time, the cotton wool in the U-­‐shaped tube is stained brown. What substance causes the colour change? to air pump
cigarette
cotton wool
U-shaped tube
A Carbon monoxide B Tar C Nicotine D Smoke particles *E13 The following diagram shows a destarched plant. The plant is put under light for several hours. Which leaf of the plant will turn blue black in an iodine test? R
water
P
soda lime
Q
sodium hydroxide
A
B
C
D
black plastic bag
S
cobalt chloride
Leaf P
Leaf Q
Leaf R
Leaf S
14 Plants are important to all living things on Earth because (1) they balance the amount of carbon dioxide and oxygen in nature. (2) they convert light energy from the sun to chemical energy stored as food. (3) they provide camouflage (掩飾) for animals. A B C D (1) and (2) only (1) and (3) only (2) and (3) only (1), (2) and (3) E15 Which part of the human breathing system does the diffusion of oxygen into blood take place? A Trachea B Bronchi C Diaphragm D Air sacs 16 Which air pollutants can cause respiratory illnesses? (1) Carbon dioxide (2) Carbon monoxide (3) Nitrogen oxide (4) Sulphur dioxide A (1) and (2) only B (3) and (4) only C (1), (2) and (3) only D (1), (3) and (4) only *E17 If all green plants on Earth died, what would be the consequences? (1) All animals would die because there is no food for them. (2) All animals would die because there is not enough oxygen for respiration. (3) All animals could survive because some animals can feed on the others. A (1) and (2) only B (1) and (3) only C (2) and (3) only D (1), (2) and (3) **18 The following graph shows the gas exchange of a leaf throughout a day. When does the plant undergo photosynthesis? D net uptake of
carbon dioxide
of carbon
dioxide
net release
A B C 0
0 – 24 hour 0 – 12 hour 6 – 18 hour 6
12
18
24
Time of the day (hour)
12 − 24 hour *19 The following experiment is aimed to find out when plants take in or give out carbon dioxide. aluminium foil
soda lime
hydrogencarbonate
indicator
1
2
3
4
The setup is put under bright light for 30 minutes. What is the colour change of the hydrogencarbonate indicator in test-­‐tube 3? What is the explanation? Colour Explanation A Red The leaf absorbs carbon dioxide and gives out oxygen. B Red The rate of photosynthesis is the same as the rate of respiration. C Yellow There is no photosynthesis but only respiration. D Yellow There is not enough oxygen for the leaf to breathe. *20 All test-­‐tubes are put under bright light for 30 minutes. Which test-­‐tube (among 1 to 4) gives the same result as that of X? soda lime
aluminium foil
grasshopper
hydrogencarbonate
indicator
A B C D X
1
2
3
4
1 2 3 4 B
True or false questions
E1 The volume of the space inside the chest increases when the diaphragm moves up. E2 The pressure inside the chest increases when the diaphragm moves up. E3 The first living thing of a food chain is a primary producer. E4 Energy is passed from one organism to another along a food chain. 5 Carbon dioxide can turn both lime water and hydrogencarbonate indicator milky. 6 Photosynthesis is the reverse of respiration because it changes carbon dioxide and water into food and oxygen. E7 Air sacs in lungs are covered with many capillaries for oxygen diffusion. 8 Plants do not need gaseous exchange because they do not have breathing system. E9 The Air Pollution Index is determined by the Health Department. If the index is very high, people are advised not to take vigorous outdoor exercises. 10 Lime water can be used to test for oxygen. C
1 2 3 Fill-in-the-blanks
Burning of food and respiration are similar since both of them give out ___________________________and_______________. The fire triangle shows the three things needed for a fire to occur, they are _______________, _______________ and _________________. Food can provide us with _______________ for all body activities which can be measured by a __________________. 4 E5 E6 E7 E8 E9 Starch can turn iodine solution _________________while carbon dioxide can turn hydrogencarbonate indicator _______________. The volume of the space inside the chest increases when the _______________moves down. The pressure inside the chest increases when the _____________move downwards and inwards. When the amount of carbon dioxide in the blood increases, the __________________________in our brain sends out signals to make us breathe faster. When the ___________________ contract, the ribs move upwards and outwards. In the balloon-­‐bell jar model which shows the action of the diaphragm, the Y-­‐piece represents the _______________. E10 _____________________ refer to the gases which can trap heat and prevent it from leaving the Earth’s atmosphere. D
Short questions
1 How do leaves of terrestrial green plants obtain carbon dioxide for photosynthesis? _________________________________________________________________________________________
_________________________________________________________________________________________ *2 The following is a destarched plant. Leaf A is covered by a black bag. The plant is then put under sunlight for several hours. Predict and explain the results if leaf A and leaf B are tested for starch. B
A
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________ 3 The following word equation shows the relationship between respiration and photosynthesis. Name processes A and B, and substances X and Y? A
X
Y + water
+ food
B
______________________________________________________________________________________________
______________________________________________________________________________________________
______________________________________________________________________________________________ *E4 A food web is shown in the following diagram. killer whale
seal
penguin
fish
blue whale
krill
microscopic algae
Find out all the food chains in this food web. _________________________________________________________________________________________
_________________________________________________________________________________________ E5 List the producers, primary consumers and secondary consumers in the following food web. killer whale
seal
penguin
fish
blue whale
krill
microscopic algae
_________________________________________________________________________________________
_________________________________________________________________________________________
6 E7 *E8 What are the reasons of using the following to put out fire: a carbon dioxide fire extinguisher; b water _________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________ Use the following organisms to construct a food chain: Bird, grass, spider, snake, grasshopper _________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________ The following diagram shows the steps of the test for starch in a leaf. What is/are the mistake(s) in the steps? Give reasons. boiling water
alcohol
step 1
step 2
hot water
hydrogencarbonate indicator
white tile
step 4
step 3
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________ **E9 The following diagram shows the bell-­‐jar model. If the rubber sheet is punctured (刺穿), what would happen to the balloons when the rubber sheet is pulled down? Explain briefly. glass tube
Y-piece
balloons
rubber sheet
_________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________ 10 Do you agree that people should be allowed to smoke cigarettes in restaurants? Give one reason for your answer. _________________________________________________________________________________________
_________________________________________________________________________________________
_________________________________________________________________________________________ E
Long questions
E1
The following graph shows the change in carbon dioxide concentration in the
atmosphere and the change in average temperature of the world from 1970 to
2000.
370
360
-­‐ 14.50 CO2 concentration Temperature -­‐ 14.45 -­‐ 14.40 355
-­‐ 14.35 350
-­‐ 14.30 345
-­‐ 14.25 340
-­‐ 14.20 335
-­‐ 14.15 330
-­‐ 14.10 325
320
1970
-­‐ 14.05 1975
1980
1985
1990
1995
2000
2005
Year
a b c State the relationship between the carbon dioxide concentration and the average temperature of the world. __________________________________________________________________________________
________________________________________ Calculate the percentage increase of carbon dioxide concentration from 1970 to 2000. __________________________________________________________________________________
________________________________________ Calculate the percentage increase of the average temperature of the world from 1970 to 2000. __________________________________________________________________________________
________________________________________ Temperature (°C) Carbon dioxide concentration (ppm)
365
d e What phenomenon is being shown by the above graph? _____________________________________________________________ Suggest one method to decrease carbon dioxide concentration in the atmosphere. __________________________________________________________________________________
__________________________________________________________________________________
__________________________________________________________________________________ E2 The following diagram shows the human breathing system. A
C
B
E
D
F
a b c d e Label structures B, C, D, E and F. __________________________________________________________________________________
__________________________________________________________________________________
___________________ Which structure(s) in the diagram move(s) upwards when a person breathes in? _____________________________________________________________ Which structure(s) in the diagram move(s) upwards when a person breathes out? _____________________________________________________________ Describe briefly how air is filtered when it passes through structure A. __________________________________________________________________________________
__________________________________________________________________________________
___________________ There are millions of structure D in the lungs. Explain why the number of structure D is so large? __________________________________________________________________________________
__________________________________________________________________________________
__________________________________________________________________________________
Science Edited By Able Exercise @ 2015 *3 The following diagram shows an experiment to study the effect of carbon dioxide concentration on the rate of photosynthesis in plants. The change of carbon dioxide concentration is done by changing the concentration of sodium hydrogencarbonate (NaHCO3) solution. The rate of photosynthesis is measured by the number of gas bubbles given out from the plant per minute. sodium
hydrogencarbonate
a plant
solution
The result of the experiment is listed in the following table. Concentration
of NaHCO3
0
1
2
3
6
13
28
52
solution (%)
Number of
gas bubbles
given out per
minute
a List two factors that may affect the rate of photosynthesis and should be kept constant during the experiment. _____________________________________________________________ b Suggest what gas is given out from the plant during the experiment. _____________________________________________________________ c How to identify the gas given out? __________________________________________________________________________________ d Why the rate of photosynthesis can be measured in terms of the Science Edited By Able Exercise @ 2015 number of gas bubbles given out per minute? __________________________________________________________________________________ __________________________________________________________________________________ e Use the data in the table to plot a graph showing the relationship between carbon dioxide concentration and the rate of photosynthesis. f What conclusion can you draw from this experiment? _____________________________________________________________ _____________________________________________________________ www.ableeducation.com.hk https://sites.google.com/site/ableexercise/ Science Edited By Able Exercise @ 2015 **E4 The following is a food web. eagle
lizard
snake
rodent
grasshopper
grasses
bushes
a What is a food chain? __________________________________________________________________________________
__________________________________________________________________________________ b List one of the longest food chain in the above food web. __________________________________________________________________________________ c List the producers, primary consumers and secondary consumers in the above food web. __________________________________________________________________________________
__________________________________________________________________________________ __________________________________________________________________________________
__________________________________________________________________________________ d What will happen to the number of snake and grasshopper if all the rodents suddenly died from a certain disease? __________________________________________________________________________________
__________________________________________________________________________________ Science Edited By Able Exercise @ 2015 __________________________________________________________________________________
__________________________________________________________________________________ *E5 The following diagram shows an experiment to study the different conditions for photosynthesis. All leaves are collected from a destarched plant. A
B
C
D
muslin
cloth
soda lime
water
hydrogencarbonate
black box
indicator
a The colour of the hydrogencarbonate indicator was red at the beginning of the experiment. What would be the colour change of the hydrogencarbonate indicator in test-­‐tubes A, B and D at the end of the experiment? __________________________________________________________________________________
__________________________________________________________________________________ b Explain why the colour of the hydrogencarbonate indicator in test-­‐tube C remained red at the end of the experiment. __________________________________________________________________________________
__________________________________________________________________________________ www.ableeducation.com.hk https://sites.google.com/site/ableexercise/ Science Edited By Able Exercise @ 2015 _____________________________________________________________
c After the experiment, the leaves were tested for the presence of starch. Which leaf / leaves would have a positive result? __________________________________________________________________________________ d Referring to test-­‐tube A, explain i the colour change of the hydrogencarbonate indicator, and ii the result of the test for starch. __________________________________________________________________________________ __________________________________________________________________________________
__________________________________________________________________________________ __________________________________________________________________________________