ch 9 microorganisms tc[1]

7/31/2019 Ch 9 Microorganisms Tc[1]

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CHAPTER 9 MICROORGANISMS AND THEIR EFFECTS ONLIVING THINGS

1. CLASSIFICATION OF MICROORGANISMS

Microorganisms Characteristics Sizea. Viruses smallest size 20nm-400nmb. Bacteria unicellular, four basic shapes(rod like, comma-

shaped, spiral-shaped, spherical), binary fission,nutrition (photosynthetic, saprophytic, parasitic)

0.1- 10m

c. Fungi unicellular or multicellular, asexually and sexual,nutrition (saprophytic,parasitic)

10- 100m

d. Protozoa unicellular, 2-1000me. Algae unicellular or multicellular, contain chlorophyll

and cellulose cell walls, carry outphotosynthesis, sexual and asexual

10- 10000m

2. FACTORS THAT AFFECT THE GROWTH OF MICROORGANISMa. Nutrientsb. Lightc. Water d. Temperaturese. pH

3. USEFUL MICROORGANISMSa. Food digestionb. Decaying processc. Medicined. Agriculturee. Industry

4. HARMFUL MICROORGANISMa. Microorganisms that cause disease are called pathogens.b. Examples of diseases caused by pathogens: Tooth decay SARS and etc.

c. Pathogens reproduce rapidly, can slow down the normal growth and metabolic activitiesof body cells and tissues.

d. Pathogens produce toxins that can kill cells.

Microorganisms and diseases

Pathogens Disease Symptoms Transmission

Viruses Common cold Sore throat,runny nose,watery eyes

Air

Dengue fever Fever,headache,runny nose

Vector(Aedes)

hepatitis Fever,headache,nauseamuscle ache

Contaminatedfood,water

Aids Diarrhoea,loss of appetite,weight loss

Physical contact

Fungal Tinea White spots, change theskin colour

Physical contact

Ringworm Scaly,round,itchy patches Physical contactProtozoa Malaria Fever,headache,nausea Vector(anopheles

Dysentery Diarrhoea Contaminated foodand water

SES 1511 Kelantan 2007 *The bolded and italic letter is the answer 163


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Bacteria Cholera Diarrhoea,thirsty,dry lips Contaminated foodand water

Gonorrhoea Severe cramps,fever,vomiting

Physical contact

Syphilis Sore on the mouth,rash,

fever

Physical contact

Tuberculosis Racking cough,sputumcontains blood,fever,weight loss

Air

Methods of transmission of human diseases Physical contact- Examples:Gonorrhoea, syphilis, ringworm, athletes foot, hepatitis

B, AIDS.

Air- Common cold, tuberculosis

Contaminated water- cholera, hepatitis A

Contaminated food- cholera, hepatitis A

Vector- animals that carry pathogens from person to person.Examples of vectorsare mosquitoes and houseflies. (Cholera, malaria, dengue fever)

5. WAYS TO PREVENT INFECTION CAUSED BY MICROORGANISMS:a. Control of vectors

i. Mosquito- related to its life cycle and habits.- draining swamps, covering the surfaces of ponds with oil, use Abate, rear larvae-

eating fish.ii. Hou s efly- keeping our surroundings clean- disposing garbage in plastic bags- close rubbish bins- hygienic disposal of faeces- keeping food covered

- spraying insecticideb. Various methods of sterilizationi. Autoclave- high temperature(121C) and pressure.ii. Boiling- 100C(cannot kill a spores)iii. Heat- expose to strong heativ. Disinfectant- chemical that kill microorganisms. Used to clean surgical

apparatus, sickroom, drains, kitchen utensils.Examples: bleaching powder,formaline

v. Antiseptic- Chemical used to kill microorganisms on skin or wound.Examples:alcohol, acriflavin, iodine

vi. Chemical- chemical can kill microorganisms.vii. Radiation- exposure to ionizing radiations such as gamma rays and ultraviolet

light

viii. Ultraviolet light- used to kill microorganisms in the air in hospitals and operatingtheatre.ix. Gamma ray- Used to sterilize injection needles, syringes and dressing.

c. Immunity- The immune system is the bodys main defence against pathogens.- It recognizes, attacks, destroys and remembers each type of pathogen that enters

the body.- There are two types of immunity: Active immunity (body produces antibodies) and

Passive immunity(body received antibodies)i. Natural A c tive Immunity- Develops naturally after a person is infected with a pathogen.- Very effective and may last for life.- Examples: recovery from diseases such as chicken pox and mumps.

ii. Artific ial a c tiv e immunity- acquired through immunization.



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- Involves the use of vaccine that contains weakened pathogen.- Examples: injection of vaccine.iii. Natural p a ss ive immunity .- acquired by the transfer of maternal antibodies to her offspring via the placenta or

breast milk.- Examples: Breast-feeding. An infant receives from the mother because antibodies

are present in the mothers milk.iv. Artific ial pa ss ive immunity- Induced by injection of serum taken from an individual already immuned to a

particular antigen.- Examples: Antiserum is injected to give immediate protection or to give rapid help in

treating a disease.

Importance of Immunity

Helps to prevent the spread of diseases.

Vaccination is used to fight infection and prevent epidemic outbreaks of diseaseor deaths.

6. HOW DISEASES CAUSED BY MICROORGANISMS ARE TREATED

a. Modern cures- Use of synthetic medicines, antiserum, antibiotics and surgery.- Antibiotics:

chemical compound obtained from microorganisms or synthesized.

Use to destroy or inhibit the growth of microorganisms.

Can be taken orally in pill or liquid or injected.

Common antibiotics include penicillin, aureomysin, streptomysin andtetracyclines.

- Viral diseases cannot be cured by using antibiotics.- Malaria can be cured by using drugs such as quinine, paludrine and chloroquinine.

b. Traditional cures- Made from leaves, stems, roots, barks and flowers of plants or body parts of animals.- Examples: Tongkat Ali root.

Danger of using drugs without medical advise and through unauthorized prescription.

Can produce side effects.

Can cause allergies

Can lead to the development of resistant strains of microorganisms.



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Nutrie nt

PAPER 1

1. The diagram shows a type ofbacteria

What is the name of thebacteria?

A Spirillum C CoccusB Bacillus D Vibrio

2. Which of the following statement is true about virus?

A Virus are saprophyte

B Virus can be crystallized

C Virus contains cytoplasm

D Virus can reproduce outside a living cell

3. The Diagram shows a type of microorganism.

Which of the following is a characteristic of this microorganism?

A It is a parasiteB It has cellulose cell wallC It does not have chlorophyllD It reproduces by binary fission

4. The Diagram shows an information about the type of microorganisms .

P : YeastQ : EuglenaR : Salmonella

S : Amoeba

Which of the above microorganisms are classified as protozoa?

A Q and R

B P and SC Q and SD P and R


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DiseasesVirusFungi Bacteria ProtozoaCommon coldSyphilis Hepatitis Tuberculosis

5. Which of the following shows the microorganisms in descending order of size from thelargest to the smallest?

A Bacteria, fungi, virusesB Fungi, bacteria, virusesC Viruses, fungi, bacteriaD Viruses, bacteria, fungi

6. Which of the following microorganisms can build their own food?

A MucorB SpirogyraC ParameciumD Plasmodium

7. Which of the following is a bacillus bacteria?

A B C D

8. Which of the following is a pathogen ?

A YeastB SpirogyraC Plasmodium

D Bacteriophage

9. Which of the following pairs is correct about the microorganisms and disease related?

ABCD

10. The diagram shows a type of microorganisms.

Which of the following is related to the microorganisms?

A All are parasitesB Contain chlorophyll

C Reproduce inside living host cellsD Obtain food from dead organics materials



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11. The diagram shows a type of microorganisms.

Name the microorganisms.

A PlasmodiumB BacteriophageC Vibrio choleraeD Tubercle bacillus

12. Which of the following is the symptom of Hepatitis A and B?

A FeverB Runny noseC Watery eyesD Weight loss

13. Which of the following is sex transmitted disease?

A MalariaB Dysentery

C GonorrheaD Tuberculosis

14. Why do we always wash our hands after handling microorganisms?

A The microorganisms are deadB We want to kill the microorganismsC The microorganisms can turn harmfulD We want to get rid of the microorganisms from our hand

15. What is the use of microorganisms in food digestion?

A As vaccinationB Produce antibioticsC Break down cellulose into simple sugarD Release enzymes to break down dead organisms

16. Which of the following can affect the growth of microorganisms?

A OxygenB Nutrient

C Size of container D Method of sterilisation



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17. The diagram shows a life cycle of a mosquito.

Q

P

R

S

Which of the following is the most suitable method to control mosquitoesin stage P?

A Use abate

B Sleep in a netC Use insecticideD Covering ponds with oil

18. Which of the following disease spread by mosquitoes?

A CholeraB MalariaC RingwormD Hepatitis A

19. Which of the following microorganisms can be spread through water?

A C

B D

20. Which of the following disease can be transmitted by air?

A AIDSB TineaC CholeraD Tuberculosis



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21. The following information shows the symptom of a disease.

Attack reproductive organ Scar tissue formation Burning sensation while urinating

What is the disease?

A AIDSB Hepatitis BC GonorrheaD Tuberculosis

22. Which of the following is a harmful microorganisms?

A DecomposerB PlasmodiumC Transgenic bacteriaD Nitrogen fixing bacteria

23. Which of the following immunity is acquired by vaccination?

A Natural active immunityB Artificial active immunityC Natural passive immunityD Artificial passive immunity

24. Which of the following is the optimum pH for bacterial growth?

A pH 2B pH 5C pH 7D pH 12

25. The diagram shows four nutrient agar which are kept under different temperaturesand intensity.

P

7CDark

Q

20CSunlight

R

35CDark

S

37CSunlight

Which nutrient agar will have most bacteria colonies after three days?

A PB QC R

D S



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Petri dishTemperature (0C)pHP

26. Which of the following diseases can be cured by using antibiotics?

A CholeraeB Hepatitis AC Dengue fever D Common cold

27. Which of the following pair is correct about disease and the method of transmission?

Disease Method of transmissionA Hepatitis VectorB Tuberculosis Water C Gonorrhea Air D Ringworm Contact

28. What is usually used to sterile human skin before an injection?

A ChemicalsB AntisepticsC DisinfectantD Distilled water

29. Which of the following can be used to sterile operating instruments in hospitals?

A HeatB Chemical

C DisinfectantD Ultraviolet light

30. What is the most suitable method to kill microorganisms and their spores?

A BoilingB Heat in water C Use antisepticD Heat in autoclave

31. A mosquito is a vector.Which of the following is correct about the vector?

A Cause diseasesB Microorganisms serves as hostC Can be infected by microorganismsD Transmits pathogen from one person to another



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Q2512R377S403

32. The table below shows the temperature and pH of some bacteria culture in apetri dish. Which petri dish has the most bacteria colonies after two days?

A

BC

D

33. The diagram shows a way to transfer pathogen.

Vector

FaecesFood

Which of the following pathogen can be transfer this way?

A PlasmodiumB Vibrio choleraeC Tubercle bacillusD Human Immunodeficiency virus

34. The table below shows four test tubes U, V, W and X which are filled with glucosesolution and yeast, and placed under different conditions.

Test tube Temperature (C) pH valueJ 30 4

K 30 7

L 40 4

M 40 7

Which of the following test tubes will produce the most gas bubbles?

A J C LB K D M

35. Which of the following reacts with yeast to produce carbon dioxide in a dough?

A Water C FlouB Sugar D Oil

36. Four paper discs are soaked in different antibiotic solutions and placed on a nutrientagar which contains bacteria culture. After two days, the results are shown in thediagram below. Antibiotic in which paper disc is the least effective in killing?

A

BD

C



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37. Which of the following is a traditional treatment?

A HerbalB SurgicalC AntiserumD Antibiotics

38. Which of the following method is the most suitable to provide immediate protectionagainst a disease?

A VaccinationB Taking drugsC Inject antiserumD Exposed to ultra violet rays

39. The information shows the ways to prevent infection of certain disease.

Wash hand before eating Drink boiled water Always cover food

Which of the following diseases can be prevented through the above ways?

A Tuberculosis and dengueB Malaria and gonorrheaC Hepatitis and syphilisD Cholera and dysentery

40. Which of the following graph is correct to show an artificial active immunity?

A CAntibodyconcentration

inbloodAntibody concentration

in blood

Time (days)

B D

Antibody concentrationin blood Antibody concentration

in blood

Time (days)

Time (days) Time (days)



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PAPER 2

SECTION A

1. Diagram 1 shows an experiment to study the effect of the amount of yeast onthe dough.

7 7

Ruler

6 6

5 5

4 4

3 3

2 2

Dough

1 1

20 ml yeast 10 ml yeast

DIAGRAM 1

The results of the experiment are recorded in table 1.

10 ml yeast 20 ml yeast

2.6

5.4..

TABLE 1

a) Based on the above experiment, complete table 1.

b) Write down one inference based on the results of thisexperiment? The dough rises because yeast produces carbon

dioxide

[1 mark]


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???????????????.

[1 mark]

c) State the variables in this experiment

i. manipulated variable:...

ii. responding variable: .iii. constant variable: ..

d) State the conclusion from the experiment.

[3 mark]

.

[1 mark]

2. Diagram 2 shows the result of an experiment to study the effect of humidity onmicroorganisms growth

Moist bread

Dry bread

After 2 days

After 2 days

Growth of mucor

No change

DIAGRAM 2

a) State the hypothesis of the experiment?

...

...

[1 mark]b) What is the observation from the experiment?

...

[1 mark]b) State the inference from the experiment?

.. .

...

[1 mark]c) State the variables in this experiment

i) manipulated variable:

ii) responding variable: .

iii) constant variable: .. ead

[3 mark]


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3. Table 1 shows the result of an experiment to study the effect of temperature on thenumber of microbes in river water. The pH value of the river water was kept constantat 7 and the number of bacteria colonies were measured after 30 minutes at differenttemperatures.

.Tem erature Number of bacteria coloniesBeginning of experiment After 30 minutes

10 10 12

20 10 14

30 10 20

40 10 15

50 10 10

60 10 5

TABLE 1

a) Plot a graph of the number of bacteria colonies against the temperature.

Number ofbacteria colonies

25

20 X

15 X

X

10 X X

5 X

0 10 20 30 40 50 60 Temperature(C)


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b) State the hypothesis of the experiment?

..

..

[1 mark]

b) What is the relationship between the number of bacteria colonies and

temperature?

.

[1

mark]d) State the inference from the experiment?

Bac..teriaarenotactiveatlowtemperatureandwilldieat high

tem..perature.

[1 mark]e) State the variables in this experiment

i) manipulated variable: Temperature va

lue. ii) responding variable: Number o

f bacteria colonies. iii)constant variable:

p

H

v

alu

e..

[3 mark]

4. Diagram 3 shows the experiment to study the factors that affect growth ofmicroorganisms

Sterile cotton

5 cm3 nutrient


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5 cm3

nutrient 3

broth + 0.5 cm3 broth + 0.5 cm

3 5 cm nutrient3

culture bacteria +3 cm

31.0 M

Hydrochloric acidP

culture bacteria +3 cm

31.0M

Sodium hydroxidesolution

broth + 0.5 cmculture bacteria +3 cm

3distilled

Q water R

DIAGRAM 3

Test tubes P,Q and R are kept at room temperatures. After 48 hours, the content ofeach test tube was observed and recorded as shown in the table below.

Test tube ObservationP Clear

Q Clear

R Cloudy



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(a) State one inference based on the observation in test tube R.

Bacteriagrowandreproducerapidly in neutralmedium..

.

[1 mark ](b) State the hypothesis of the experiment.

Bacteriado notgrow in alkaline oracidic condition.

.

.

[1 mark ]

(c) Which test tube has the highest growth rate of microorganisms?

Test tube R.

[1 mark ]

(d) State one way to keep the constant variable.

Keepatroomtemperature.

[1 mark ]

SECTION B

1. Diagram 4 shows five different microorganisms.

J K L M N

DIAGRAM 4

a) Identify the class of microorganisms

J :Algae. M :Pr

ot

oz

oa

.

K:Bacteria . N:

Fungi

L:Virus.

..

[1 mark ]

b) Which of these microorganisms can make their own food?Algae / J

.

[1 mark ]

c) Name a disease which is caused by microorganism K.


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D

en

gu

e

/ /H

e

pa

tit

is

A

o

rB

//

Co

m

m

on

c

o

ld.

[1 mark ]



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d) Which microorganism is inactive outside its living host cells?

V

iru

s

/

L.

(e) i) State one industrial use of microorganism N.For making bread / production of alcoholic drink

.

ii) How do the organisms N reproduce?

Bybudding.

[1 mark ]

[1 mark ]

[1 mark ]

2. The graph shows the level of immunity of a man.

Antibody concentrationin blood

Level of immunity

0

Firstinjection

15 30

Second injection

45 60 Time (days)

a) What type of immunity does the graph show?

Artificialpassiveimmunity

.

b) Why is this immunity required?

Togiveimmediateprotectionagainstcertain disease .

c) What is the substance use in the injection?

Antiserum.

d) Why is the second injection needed?

[1 mark ]

[1 mark ]

[1 mark ]

Togiveenough antibodiesforprotection

.

[1 mark ]


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e) Match the immunity and action correctly.

1. Natural Active Immunity 2. Natural Passive Immunity3. Artificial l Active Immunity 4. Artificial Passive Immunity

No. Action Immunity1 Give vaccination 32 From mother to the baby through placenta 23 Acquired after recovering from infection 14 Injection of prepared antibodies 45 Injection of weakened and mild pathogen 3

6 Gained by newborn infant 2

[7 mark ]

SECTION C

1. Study the following statement .

Nutrient can affect the growth of bacteria

You are given nutrient broth, plain broth and cultured bacteria.

a. Suggest a hypothesis to investigate the above statement.

(1 mark)

b. Describe an experiment to test your hypothesis in (a) based on the following

criteria:

ANSWE R

Aim of the experiment (1 mark)

Identification of variables (1 mark)

List of apparatus and materials (2 marks)

Procedure (4 marks)

Tabulation of data (1 mark)

Hypothesis : Bacteria need nutrients for growth.

Aim : To study the affect of nutrient on the growth of bacteria

Variables

Manipulated variable : The presence of nutrient

Responded variable : The growth of bacteria

Constant variable : Type of bacteria // number of bacteriacolonies

List of apparatus and materials:

Sterile syringe, cellophane tape, glass spreader, 2 steriled petri dishescontaining nutrient agar, Bacillus subtilis culture



23/241.Food digestion

Procedure :

Label the base of each of the 2 steriled petri dishes containing nutrient agar andplain agar.

By using steriled syringe, transfer 1 cm3

of Bacillus subtilis culture into each

petri dish. Put the lids back immediately on the petri dishes.

Tape the lids with cellophane tape.

Incubate the two petri dishes upside down in a dark cupboard.

Examine the petri dishes for bacterial growth after two days.

Record the result in table.

Tabulation of data:

The Presence of nutrientNumber of bacteria

coloniesNutrient agar

Plain agar

2. a) Give four usage of microorganisms and one example for each usage. (4 marks)

b) Diagram shows four microorganisms that caused disease.

Virus forHepatitis B

Bacteria forCholerae

Microorganisms

Protozoa forMalaria

Fungi forRingworm

Study the microorganisms above and develop a concept of a pathogen.Your answer should be based on the following aspects:

Identify two common characteristics of a radio wave. Develop an initial concept of pathogen Give one example of a pathogen and give a reason for your choice Give one example of non-pathogen and give a reason for your choice Develop the actual concept. (6marks)



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.Decaying processBacteria and fungi break down the waste materials3.MedicineFungi such as penicillin produces antibiotics4.AgricultureNitrogen fixing bacteria are able to fix nitrogen to nitrates5.Industry

Bacteria are used in the production of yogurt.

ANSW E R

a)

b) i) Common characteristics

Attack the human body / destroy the human tissues

Cause diseases

ii) Initial concept Microorganisms that attack the human body and cause diseases are

pathogen

iii) Other example :

Bacteria cause Gonorrhea - destroy human tissueNon-example

Algae - Do not cause disease to human

v) Actual concept

Pathogens are microorganisms that attack the human body andcause diseases

ch 9 microorganisms tc[1]

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