auteurs Arteunis Bos Onno Kalverda Gerard Smits Ben Waas
1a HAVO | VWO
1a HAVO | VWO
vertaling Mike Wilkinson
your biology workbook
eindredactie Sally Hill
your biology workbook ISBN 978 90 345 4226 7
9 789034 542267
557696
your biology
Contents Unit 1 What is biology?
Unit 2 Plants
BASICS
6
BASICS
36
1
Alive – dead – non-living
6
1
The lifecycle of a plant
36
2
Making drawings
8
2
Roots
40
3
Magnifying
11
3
Stems
43
4
Making tables and graphs
14
4
Leaves
48
5
Growth
15
5
Edible roots, stems and leaves
53
6
Development
18
6
Designing an experiment
54
7
Main themes in biology
23
EXTRA
56
8
Biology in professional life
25
7
Twigs
56
EXTRA
26
8
Leaf morphology
58
9
The lifecycle of a common frog
26
10 Young that stay and young that go
28
SCORE SHEET DIAGNOSTIC TEST
60
EXTENSION
62
SCORE SHEET DIAGNOSTIC TEST
29
1
Sprouts and shoots
62
EXTENSION
31
2
The importance of photosynthesis
63
1
The human body in numbers
31
3
Insect galls
65
2
Cats and dogs
32
3
Man – woman – child
34
2
Unit 3 Organs and cells
Unit 4 Classification
BASICS
68
BASICS
96
1
Organs and tissues
68
1
Classifying organisms
96
2
The microscope
72
2
The domains bacteria and archaea
101
3
Microscopy
73
3
The fungal kingdom
105
4
Cells
78
4
The plant kingdom
109
5
The nucleus
83
5
The animal kingdom
113
6
Levels of biology
84
6
Other unicellular eukaryotes
118
EXTRA
86
7
Classifying into smaller groups
121
7
Cell division
86
8
The arthropod phylum
124
8
Stomata
88
9
The vertebrate phylum
131
SCORE SHEET DIAGNOSTIC TEST
89
EXTENSION
91
1
Kinship analysis
91
2
Organ systems in a dog
93
3
Organ systems in an insect
94
10 Identifying organisms
135
11 Animal project
138
EXTRA
139
12 Classifying seed-bearing plants
139
13 Practical assessment: The mussel
142
SCORE SHEET DIAGNOSTIC TEST
143
EXTENSION
145
1
Edible animals
145
2
Live fish food
147
WORKSHEETS
3
149
UNIT
3
Organs and cells
1 BASICS
unit 3 Organs and cells
Organs and tissues
exercise 1 Figure 1 shows two drawings of a torso. – Write down the names of the organs the lines point to. Use figure 1 from your textbook. – Colour in the organs in the drawings. Use a different colour for each organ.
▼ Fig. 1
exercise 2 The diaphragm divides the human torso into the chest cavity and the abdominal cavity (see figure 2). The lungs and the heart are in the chest cavity, while the liver for example and the intestines are in the abdominal cavity. Some organs go through the diaphragm. Write down three organs that are shown in figure 1 that go through the diaphragm.
▼ Fig. 2 The diaphragm divides the human torso into the chest cavity and the abdominal cavity.
chest cavity cross section 1 diaphragm cross section 2 cross section 3
68
abdominal cavity
BASICS unit 3 Organs and cells
exercise 3 In figure 2, three places are shown where a cross section can be made. Diagrams of these cross sections are shown in figure 3. Some organs are labelled with their name, but other organs have no labels. – Write down the names of the organs the lines point to. – Colour in the organs in the drawings. Use a different colour for each organ. ▼ Fig. 3
gullet
1 cross section of the chest cavity
main vein
main artery
2 cross section of the abdominal cavity, just below the diaphragm
3 cross section of the abdominal cavity, at the level of the belly button
TB ORGAN SYSTEMS, PAGE 79
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BASICS unit 3 Organs and cells
exercise 4 Write down the correct organ system next to each organ in the table. Main artery Biceps Buttock muscle Bronchus Liver Wrist artery Backbone
exercise 5 Answer the following questions. 1
Figure 4.1 shows a schematic drawing of some blood cells. Figure 4.2 shows a drawing of some cells that form a membrane. They are different shapes. What are the reasons for the differences in shape? Explain your answer.
2 Do the blood cells and the membrane cells come from the same tissue? Explain your answer.
3 It is not just organs that can be transplanted; tissues can too. If someone has suffered severe burns, a skin transplant is often a good option. The skin is an organ, but this is still called a tissue transplant. Give an explanation for this.
4 Is the extracellular material in bone tissue hard or soft? Explain your answer.
▼ Fig. 4
1
2
70
BASICS unit 3 Organs and cells
optional exercise
6
There are five statements about organ donation in the table below. In this exercise you will discuss these statements. You will do this in a group of, say, four pupils. WHAT DO YOU NEED? – Three matches for each pupil in the group – a watch (or clock) WHAT DO YOU HAVE TO DO? – Each pupil takes three matches. – Read the first statement. Then discuss with one another whether you agree or disagree with the statement. Every time you say something, you have to hand in a match. When you have no more matches left, you are not allowed to say anything any more. You have a maximum of five minutes for the discussion. – In the table, next to the first statement, make a note of how many pupils agree with the statement and how many disagree. – Repeat the discussion for the rest of the statements and fill in the rest of the table. You start with three matches every time. Statement
Agree
1
I think it should be compulsory for everyone in the Netherlands to be a donor.
2
I think people who have an unhealthy lifestyle (for example smokers and people with an alcohol addiction) do not have a right to a donor organ.
3
I think people should be able to receive an organ even if they themselves are not donors.
4
I only want to be a donor if I can decide myself who gets my organs.
5
I am going to register as a donor.
TB BASICS 2, PAGE 82
71
Disagree
2 BASICS
unit 3 Organs and cells
The microscope
exercise 7 Figure 5 shows a diagram of a microscope. – Write down the names of the parts the lines point to. – Use arrows to show the path the light takes through the microscope. ▼ Fig. 5
exercise 8 Figure 6 shows three eyepiece lenses with magnifications of 5×, 10× and 15×, and three objective lenses with magnifications of 4×, 10× and 40×. What magnifications are possible with these eyepiece lenses and objective lenses?
TB BASICS 3 PAGE 84
▼ Fig. 6 Eyepiece lenses and objective lenses.
72
3 BASICS
unit 3 Organs and cells
Microscopy
exercise 9 practical activity
FOCUSING AT THE LOWEST MAGNIFICATION WHAT DO YOU NEED? – a microscope – a ready-made specimen – drawing materials WHAT DO YOU HAVE TO DO? – Place the microscope in front of you with the arm facing you. – Check that the tube contains the eyepiece lens with a magnification of 10×. – Check that the diaphragm is opened as wide as it will go. – Check that you are using the smallest objective lens (4×). – Examine the specimen. Use figure 10 from your textbook. If you don’t see anything, take a look at figure 12 in your textbook. – Find a part of the object that looks clear by moving the specimen. RESULT – Make a true-to-life drawing of the object in the space provided. – Add names to the parts you recognise. – Write down what the object is and the magnification used under the drawing.
73
BASICS unit 3 Organs and cells
exercise 10 practical activity
FOCUSING AT A HIGHER MAGNIFICATION WHAT DO YOU NEED? – the microscope, still focused from exercise 9 WHAT DO YOU HAVE TO DO? – Check that the microscope is properly focused at the lowest magnification. – Figure 11 in your textbook shows what you have to do to get it focused for a higher magnification. You have to do this when you change from 40× magnification to 100×. You have to do this again when you change from 100× magnification to 400×. – Look at part of the object using a magnification of 400×. – Tidy away the microscope. First rotate the revolving nosepiece so that the smallest objective lens is underneath (or a part of the revolving nosepiece that does not have an objective lens attached). Then lower the stage (or raise the tube) and remove the specimen. Always hold onto the microscope by the arm and support the microscope with your other hand.
exercise 11 practical activity
THE IMAGE THROUGH THE MICROSCOPE WHAT DO YOU NEED? – a microscope – a newspaper – scissors – drawing materials WHAT DO YOU HAVE TO DO? – Cut out a piece of text in very small print from the newspaper. The cutting should be about 4cm wide and 2cm long. – Place this piece of paper over the opening in the microscope stage. Place the cutting so that the bottoms of the letters are facing you. You don’t need to fix the cutting into place with the stage clips (see figure 7). – Examine the letters using the lowest magnification. RESULT – Look for a letter ‘e’ in the text – Make a true-to-life drawing in the space provided of the letter ‘e’ as it appears through the microscope. – Stick the newspaper cutting in next to your drawing and underline a letter ‘e’.
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BASICS unit 3 Organs and cells
▼ Fig. 7
exercise 12 practical activity
SHARPNESS OF THE IMAGE THROUGH THE MICROSCOPE WHAT DO YOU NEED? – a microscope – scissors – a slide – sticky tape WHAT DO YOU HAVE TO DO? – Cut a piece off a single hair on your head. Ask the person next to you for a piece of a single hair from their head too. – Lay one hair on top of the other to make an X and press them onto the sticky side of a piece of adhesive tape. Place the sticky tape on a slide (see figure 8). – Examine the hairs under the microscope at a magnification of 100×. Find the point at which the hairs cross. – Examine the hairs at a magnification of 400×. Compare the thickness of the two hairs. RESULT Answer the following questions. 1
Can you see both the hairs in focus at the same time where they cross?
2 You want to compare the thickness of the two hairs. What do you have do to see each of the two hairs in focus in turn?
3 Which of these two people has the thicker hairs?
4 If you examine a cell through the microscope, can you see all parts of that cell in focus at the same time?
▼ Fig. 8
75
BASICS unit 3 Organs and cells
exercise 13 Answer the following questions. 1
Write down two reasons why you should always examine a specimen first using the smallest magnification. – –
2 Why must you never use the coarse focusing knob to lower the tube (or raise the stage) when you are looking through the eyepiece lens?
3 What does the letter ‘d’ look like through a microscope?
4 If you examine an object using a high magnification, it is a good idea to use the fine focusing knob to keep adjusting the focus. Explain this.
exercise 14 Answer the following questions. Use figure 9. 1
Why are thin slices made of the tissue?
2 What is the dye solution for?
3 A pathologist uses a microscope to examine liver tissue. He sees that some cells have a different shape to other cells in this tissue. What property of tissues does this observation not fit with?
TB BASICS 4, PAGE 87
76
BASICS unit 3 Organs and cells
▼ Fig. 9
Preparing specimens After a doctor has taken a sample of tissue or cells, the material is taken to a hospital pathology department or a pathology laboratory. A lab worker there prepares specimens from the material that can be examined through a microscope.
1 The tissue is mounted in wax, which makes it easier to cut very thin slices from it. 2 A microtome is used to cut extremely thin layers off the tissue sample. 3 The tissue with wax is placed on a microscope slide. 4 This machine removes the wax from the glass slides and tissue and then stains the tissue using a dye solution. 5 A cover slip is placed over the tissue, and the specimen can then be examined. 4 2 3
5 1
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4 BASICS
unit 3 Organs and cells
Cells
exercise 15 practical activity
CELLS FROM YOUR CHEEK LINING ▼ Fig. 10
WHAT DO YOU NEED? – a microscope – a plastic stirring rod – materials for preparing a slide – dye solution – drawing materials WHAT DO YOU HAVE TO DO? – Use the stirring rod to scrape along the inside of your cheek (see figure 10). You could also use your fingernail or a wooden spatula. – Transfer the scraping to a clean slide and add a drop of the dye solution. Put a cover slip over the specimen. Use figure 19 from your textbook. – Examine the specimen through the microscope at a magnification of 100×. To do this, follow the steps in figures 10 and 11 in your textbook. You will see loose cells and cells that are attached to each other or overlap. – Examine one cell at a magnification of 400×. RESULT Make a true-to-life drawing of the cell in the space provided. Label the following parts: cytoplasm – cell membrane – nucleus. – Take the slide apart. – Clean the materials you have used and dry them with a tissue.
TB PLANT CELLS, PAGE 88
78
BASICS unit 3 Organs and cells
exercise 16 practical activity
THE SKIN OF AN ONION WHAT DO YOU NEED? – a microscope – a piece of an onion – materials for preparing a slide – dye solution – drawing materials WHAT DO YOU HAVE TO DO? 1 Take a clean slide and squeeze a drop of the dye solution onto it. – Take the piece of onion and pull the food storage leaves apart. You will find a thin skin on the inside of the food storage leaf. You can use tweezers to pull it off. – Figure 19 in your textbook shows what you have to do to next to prepare a specimen from the skin of an onion. – Examine the specimen through the microscope at a magnification of 100×. To do this, follow the steps in figures 10 and 11 in your textbook. – If you have a good specimen, you will be able to see the cell walls of the skin of the food storage leaf. Compare your specimen with figure 20 in your textbook. Prepare a new specimen if necessary. – Examine how the cell walls are connected to one another. The dye shows up the nuclei clearly. The cytoplasm can be seen clearly too because of the dye. RESULT – Make a true-to-life drawing of three adjoining cells with their cell walls in the space provided. Label the parts. – Tidy your materials away.
exercise 17 practical activity
A LEAF OF WATERWEED WHAT DO YOU NEED? – a microscope – a stalk of waterweed with some leaves – water – materials for preparing a slide – drawing materials 79
BASICS unit 3 Organs and cells
WHAT DO YOU HAVE TO DO? – Take a slide and put a drop of water onto it. – Use the tweezers to pull off a leaf of waterweed and put it in the drop of water. Complete the preparation of the specimen. – Examine the specimen through the microscope at a magnification of 100×. You will see two layers of cells on top of one another. Focus on one of the two layers. – Set the diaphragm open as far as it will go and examine the specimen at a magnification of 400×. Adjust the focus sharply enough that you can see the chloroplasts in an individual cell (see figure 16 in your textbook). The chloroplasts are in the cytoplasm. The vacuole is in the middle of the cell. The nucleus is colourless and you can’t normally see it. Sometimes you can see the chloroplasts moving around with the cytoplasm. – Make a true-to-life drawing of one cell with its cell wall in the space provided. Label the following parts: chloroplasts – cell wall – cytoplasm – vacuole. – Take the slide apart. Throw away the leaf and the liquid. – Tidy your materials away.
exercise 18 practical activity
AMYLOPLASTS ▼ Fig. 11
WHAT DO YOU NEED? – a microscope – a potato – materials for preparing a slide – iodine solution (diluted) in a bottle with a pipette – drawing materials WHAT DO YOU HAVE TO DO? – Cut the potato in two. Use the blade to scrape along the cut surface (see figure 11). You then get some scrapings on the blade. All you need is a tiny bit of scrapings. – Use the scrapings to prepare a specimen in a drop of iodine solution. The iodine solution stains the leukoplasts bluish purple.
80
BASICS unit 3 Organs and cells
– Examine the specimen under the microscope at a magnification of 100×. You will see round and oval amyloplasts (see figure 18 in your textbook). You may also see pieces of cell wall. You destroyed the cell walls by scraping with the blade. – Make a true-to-life drawing of some amyloplasts in the space provided. – Tidy your materials away.
exercise 19 You have examined plant cells and animal cells. You have seen that some of the parts of plant cells are not found in animal cells. Put crosses in the table to mark the parts that are found in plant cells and the parts that are found in animal cells. Part
Found in plant cells
Cell membrane Cell wall Chloroplast Cytoplasm Nucleus Large vacuole
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Found in animal cells
BASICS unit 3 Organs and cells
optional exercise
20 practical activity
CHROMOPLASTS WHAT DO YOU NEED? – a microscope – a cherry tomato or snack tomato – water – materials for preparing a slide – drawing materials WHAT DO YOU HAVE TO DO? – Use the blade to cut off a thin piece of the tomato’s skin and carefully scrape some of the tissue away just under the skin. – Put the scraping in a drop of water on a slide and carefully place a cover slip on top. Then tap the cover slip with the handle of a mounted needle. That will make the tissue spread out a little. – Using a magnification of 40×, look for some loose cells. – Examine these cells at a magnification of 400×. In the cells you will see small red chromoplasts. RESULT – Make a drawing of a single cell with its cell wall in the space provided. Label the following parts: cell wall – chromoplast. – Tidy your materials away.
TB BASICS 5, PAGE 91
82
5 BASICS
unit 3 Organs and cells
The nucleus
exercise 21 Answer the following questions. 1
All the chromosomes in a cell have a combined length of more than 2 metres. How can they still fit inside a nucleus with a diameter of only a few hundredths of a millimetre?
2 In 2012, a company was discovered to have been selling horsemeat as beef (beef is the meat that comes from cows). Beef is more expensive than horsemeat, so the company was able to make more money. It is possible to tell whether meat comes from a horse or a cow by looking at the chromosomes in the cells. Explain this. Use table 1 in your textbook.
3 Are all the characteristics determined by the information in your DNA inherited characteristics? Explain your answer.
4 What is the name for a piece of DNA that contains the code for a single characteristic?
5 A muscle cell contains proteins, which is why the muscle cell is able to contract. A cell in the outermost layer of your skin does not make these proteins. Is that because skin cells do not have the genes for these proteins? Explain your answer.
exercise 22 Scientists all around the world have joined forces to determine the order in which the bases appear in human DNA. This project is called the Human Genome Project. The researchers used a machine that is capable of reading the order of the bases in DNA. The machine produces a graph showing the order in which the bases appear on one side of the DNA chain (see figure 12). Part of that sequence is shown below. Write down the order underneath in which the bases appear on the other side of the DNA chain. A
C
G
A
C
T
C
A
TB BASICS 6, PAGE 93
83
▼ Fig. 12
6 BASICS
unit 3 Organs and cells
Levels of biology
exercise 23
Fill in the table below. The first column contains descriptions of research carried out by biologists. In the second column, write down the level of biology at which this research takes place. Research
Level of biology
All kinds of species that used only to be found in the south of the Netherlands are now found throughout the Netherlands. Researchers think this is because the weather has become warmer in recent years. Chloroplasts from spinach leaves are used in a study of photosynthesis. In a study of how the stomach works, a camera is inserted into the stomach via the gullet using a thin tube. A molecular biologist determines which bacterium caused a wound infection by looking at its DNA. A pathologist examines a tissue sample from a woman’s breast to see if it contains cancer cells. Students are investigating the relationship between birds and shellfish in the Waddenzee. A study shows that the habitat of the Cross River gorillas (a group of gorillas that live in the area where Cameroon borders Nigeria) has more than halved in size. Zebra fish are used to study the development from egg to adult fish.
exercise 24 Answer the following questions. 1
Lydia (see figure 2 in your textbook) turned out to have an abnormality in her DNA that meant that the bile ducts had not formed properly. At what level of biology was the cause of the fact that the bile ducts were closed?
2 At what level of biology were the consequences of the abnormality in Lydia’s DNA?
3 What main theme in biology is the problem with the formation of the bile ducts connected to?
4 Snowy owls live in the artic regions, where there is often snow (see figure 13). Researchers say they evolved from owls with brown feathers. A change in the DNA means that the skin cells make much less pigment. That is why the feathers are white. Being white has an advantage in arctic regions. Many other animals that live there are white. Write down three levels at which evolution, another main theme of biology, plays a role here.
5 You could also call tissues a level of biology. Between which two levels does the level of tissues come?
84
BASICS unit 3 Organs and cells
▼ Fig. 13
You have now completed all the basics for this unit. – Use the answer book to check whether you have answered the exercises in the basics correctly. Your teacher will tell you whether or not you should do the extra basics. – If you have to do the extra basics, turn to page 96 of your textbook. – If you do not have to do the extra basics, study the summary on page 99 of your textbook. This list of objectives describes what you should know and be able to do. You can use it to prepare for the diagnostic test.
85
7 EXTRA
unit 3 Organs and cells
Cell division
exercise 25 Answer the following questions. 1
In the body of a boy aged 12, millions of cells are constantly being created. What are all these cells for?
2 Before a cell divides, two nuclei are created. What happened to the DNA before these two DNA could be created?
Use table 1 in your textbook to help you answer questions 3 and 4. 3 Figure 14 shows you a photo of an onion cell during cell division. How many chromosomes were there in the onion cell at the point when the photo was taken? Explain your answer.
4 How many chromosomes does each daughter cell contain after the onion cell has divided?
5 What process makes the daughter cells become just as big as the parent cell after cell division?
6 Specialised cells often lose their ability to divide. How is it that there are still cells present that are capable of dividing?
7 What are stem cells?
▼ Fig. 14 An onion cell during cell division.
86
EXTRA unit 3 Organs and cells
exercise 26 practical activity
CELL DIVISION IN THE ROOT TIP OF A YOUNG ONION ROOT WHAT DO YOU NEED? – a microscope – a ready-made specimen of a longitudinal section of a young onion root – drawing materials
▼ Fig. 15 Cells in the root tip of an onion.
WHAT DO YOU HAVE TO DO? – Examine the specimen using a magnification of 100×. The root tip contains cells that are dividing. The chromosomes are visible in these cells. These cells show the different phases of normal cell division. – Find a cell where the chromosomes are visible. Examine this cell using a magnification of 400×. RESULT – Make a drawing of this cell in the space provided. Label the chromosomes.
TB EXTRA 8, PAGE 98
87
8 EXTRA
unit 3 Organs and cells
Stomata
exercise 27 practical activity
▼ Fig. 16
STOMATA INTRODUCTION In this practical activity, you will examine the stomata of a leaf. Suitable plants are tulips, lilies and Tradescantia (spiderwort). WHAT DO YOU NEED? – a microscope – a leaf from a plant – materials for preparing a slide – drawing materials
WHAT DO YOU HAVE TO DO? – Fold the leaf in half and carefully pull the two halves apart along the fold. You will then see a transparent skin (see figure 16). Cut off a small piece of this skin. (Some leaves don’t tear when you fold them. In that case, you can cut into the leaf a little bit with the blade and then tear it.) – Prepare a specimen from this piece of epidermis. – Examine the specimen through the microscope at a magnification of 40×. Find a section where the cells are clearly visible. Examine the specimen using a magnification of 100× and look for a section with a stoma. – Make a drawing of a stoma with some epidermal cells in the space provided. Label the following parts: stoma – epidermal cell.
You have now completed all the extra basics for this unit. – Use the answer key to check whether you have answered the exercises for the extra basics correctly. – Study the summary on page 99 of your textbook. This list of objectives describes what you should know and be able to do. You can use it to prepare for the diagnostic test. 88
DIAGNOSTIC TEST DIAGNOSTIC TEST
unit 3 Organs and cells
9
2 DIAGNOSTIC TEST SCORE SHEET
objective
1 A
B
C
1
objective
2
5
1
3 4
objective
2
2
1=
3
2=
4
3= 4= 5= 6=
5
7=
6
8= 9=
objective
10 =
Parts of cells
11 =
objective
6 Only found in the bee orchid
3
Nucleus
1=
Cell membrane
2=
Cell wall
3=
Cytoplasm
4= 5=
Large central vacuole
6=
Nuclear membrane
objective
Chromoplasts
4
Plastids
1 2
objective
3 4
7 A
5
1
6
2 3 4
7
5
8
6 7 89
B
DIAGNOSTIC TEST unit 3 Organs and cells
objective
extra objective 10
8
Level of
1
Example
biology
2
Molecule
3 –
–
Cell
4 Organ
Use the answer key to check whether you have answered the diagnostic test questions correctly. – If you did not make any mistakes, start the extension. – If you made mistakes in one or more of the objectives, study those objectives in the summary. Work out exactly what you did wrong. Then you can start on the extension.
Organism
Population
Ecosystem
extra objective 9 A
B
C
D
1 2 3 4
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1
EXTENSION
unit 3 Organs and cells
Kinship analysis
exercise 1 Answer the following questions.
1
Chao’s parents have died in a tragic car accident. Chao’s parents were very rich. At the funeral, someone comes up to him and introduces himself as Chao’s brother Jianguo. Chao has never heard of him and thinks he is just out to get the inheritance. Chao suggests carrying out a DNA kinship analysis (‘familial testing’). Figure 17 is a schematic drawing of part of the results of the analysis. Could Jianguo really be Chao’s brother, based on this part of the DNA kinship analysis? Explain your answer.
▼ Fig. 17
mother
father
Chao
Jianguo
2 Usually, ten or more pieces of repeating DNA are examined in a kinship analysis. A repeating piece of DNA is often called a marker. Sometimes it is possible to draw a conclusion from a smaller number of markers. Table 1 shows the results of a kinship analysis in which five markers were examined. The numbers give the number of repeats of each marker. Can it be concluded that the woman is not the child’s biological mother, based on these results? What about the man? Explain your answer.
3 A forensic investigation is an investigation into the causes of crimes by examining traces left by offenders. DNA tests play an important role. But the information from DNA tests is often not enough to identify the offender. In a burglary, the home owner was killed with a knife. Blood from a second person was found on the floor next to the blood of the victim. A DNA profile was made from the blood of this second person. It turned out that this DNA profile matched the DNA profile of a friend of the victim’s wife.
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EXTENSION unit 3 Organs and cells
However, just because the DNA profile of the blood that was found matches the DNA profile of the wife’s friend, this does not mean the friend was the culprit. Explain this.
▼ Table 1 exercise 2
Woman
Man
Child
Marker 1
7, 8
8, 12
8, 12
Marker 2
12, 19
12, 14
12, 13
Marker 3
23, 27
26, 27
23, 27
Marker 4
11, 18
14, 15
9, 18
Marker 5
6, 12
9, 14
6, 14
exercise 2 practical activity
ISOLATING DNA INTRODUCTION Before a DNA profile can be created, the DNA has to be isolated from the cells. In this practical activity, you will be isolating some of your own DNA. WHAT DO YOU NEED? – a test tube – a glass beaker (100 mL) – a 10 mL syringe (or measuring cylinder) – a 1 mL syringe – a water bath at 60°C – ORS solution (ORS is a substance with a lot of salt. It is used when someone becomes dehydrated, for example because of diarrhoea) – washing-up liquid – cold alcohol – gloves WHAT DO YOU HAVE TO DO? – Put 10 mL of the ORS solution in the glass beaker. – Chew on your cheeks gently for about half a minute. Then put about 10 mL of ORS solution in your mouth and flush it around. Spit the ORS solution (with cheek lining cells) back into the glass beaker. – Add 1 mL of washing-up liquid to the glass beaker and carefully swill the liquid in the glass beaker around. (It must not start to foam. The washing-up liquid breaks open the cells, releasing the DNA into the solution.) – Take 6 mL from the solution and put it in a test tube. Place the test tube in a water bath at 60°C. – After 20 minutes, take the test tube out of the water bath and carefully add 6 mL of cold alcohol. Use gloves. If you get the cold alcohol on your skin, you will get a burn. – After approximately 5 minutes, you will see a white ‘band’. This is your DNA.
▼ Fig. 18
DNA
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2 EXTENSION
unit 3 Organs and cells
Organ systems in a dog
exercise 1
Figure 19 shows you a diagram of the organs in the body of a dog. Colour in the drawing: – Colour all organs that are part of the skeletal system yellow; – Colour all organs that are part of the muscular system orange; – Colour all organs that are part of the digestive system green; – Colour all organs that are part of the respiratory system blue; – Colour all organs that are part of the circulatory system red; Colour all organs that are part of the nervous system purple; Colour all organs that are part of the excretory system brown. ▼ Fig. 19
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3
EXTENSION
unit 3 Organs and cells
Organ systems in an insect
exercise 1 Figure 20 gives four outlines of a grasshopper. – Draw in the correct organs in each grasshopper, using figure 50.2 from your textbook. – Colour in the drawings. ▼ Fig. 20
digestive system
circulatory system
nervous system
reproductive system
Use the answer key to check whether you have done the exercises for the extension material correctly.
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