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Flashcards in Biodiversity and classification of microorganisms questions Deck (65):
1

1.1

Name the 5 kingdoms into which organisms are divided, according to the five-kingdom system.

 

  • Monera
  • Protista
  • Fungi
  • Plantae
  • Animalia

2

1.2

Give the name of the kingdom into which the following organisms are classified

1.2.1 protozoans

1.2.2 aerobic bacteria

1.2.3 moulds, mushrooms and yeasts

 

1.2.1 Protista

 

1.2.2 Monera

 

1.2.3 Fungi

3

1.3

Living organisms in the 5 kingdoms are divided into two groups according to their cell structure:

Prokaryotes and Eukaryotes

Tabulate THREE  differences between these two groups

Prokaryotes:

1. Organisms without a true nucleus

2. Their DNS is not enclosed by a nuclear membrane and occurs freely in the cytoplasm

3. Membrane-bound organelles are absent

Eukaryotes

1. Organisms with a true nucleus

2. Their DNA is enclosed by nuclear membrane inside the nucleus

3. Membrane-bound organelles occur in the cytoplasm

 

4

1.4

What is an infectious disease?

1.4 Any disease that is caused by a microorganism

5

Question 3 

Indicated whether the following characteristics of viruses are TRUE or FALSE

If false, write correct characteristic down

 

3.1

Smallest of all micro-organisms

 

 

 

3.1

TRUE

6

Question 3 

Indicated whether the following characteristics

of viruses are TRUE or FALSE

If false, write correct characteristic down

 

3.2 

Truly living, because they show the seven characterisitics of life

 

3.2

FALSE

Not actually living because they do not show the seven characteristics of life

7

Question 3 

Indicated whether the following characteristics

of viruses are TRUE or FALSE

If false, write correct characteristic down

 

3.3

​Obligate intercellular parasites

 

3.3

FALSE

Obligate intracellular parasites

8

Question 3 

Indicated whether the following characteristics

of viruses are TRUE or FALSE

If false, write correct characteristic down

 

3.4

Pathogenic and cause many deadly diseases

 

3.4

TRUE

9

Question 3 

Indicated whether the following characteristics

of viruses are TRUE or FALSE

If false, write correct characteristic down

3.6

Not dependant on host cells

 

3.6

FALSE

Dependant on host cells

 

10

Question 3 

Indicated whether the following characteristics

of viruses are TRUE or FALSE

If false, write correct characteristic down

3.7

Usually contains DNA and RNA

 

3.7

FALSE

Usually contain DNA or RNA

11

Question 3 

Indicated whether the following characteristics

of viruses are TRUE or FALSE

If false, write correct characteristic down

3.8

Host and sometimes even tissue-specific

 

3.8

TRUE

12

Question 3 

Indicated whether the following characteristics

of viruses are TRUE or FALSE

If false, write correct characteristic down

3.9

Display only one characteristic of life,

i.e. respiration

 

3.9

FALSE

Show only one characteristic of life,

i.e. reproduction

13

Question 7 page 1.48

Bacteria occur everywhere. From both an economic and ecological point of view, bacteria can be beneficial or harmful (to plants, animals and humans).

Answer the following questions about bacteria.

Refer to next card for questions

14

7.1

The autotrophic bacterium,

Thiobacillus, plays a role in the extraction of copper

7.1.1

What is menat by an autotrophic bacterium?

 

7.1.1

 

The bacterium contains chlorophyll

and can thus photosynthesis

and produce it's own carbohydrates

15

7.1

The autotrophic bacterium,

Thiobacillus, plays a role in the extraction of copper

 

7.1.2

What is the shape of this bacterium?

 

7.1.2

rod-shaped

16

7.1

The autotrophic bacterium,

Thiobacillus, plays a role in the extraction of copper

7.1.3

Explain the role autotrophic bacteria play in food chains and food webs.

 

7.1.3

They form the first link in food chains, i.e. the producers.

Energy that is trapped in the food that is produces by autotrophic bacteria is transferred from one organism to another in the food chain.

17

7.1

The autotrophic bacterium,

Thiobacillus, plays a role in the extraction of copper

7.1.4

Eplain how autotrophic bacteria and protists (algae) play a role in the oxygen-carbon dioxide-balance

 

 

7.1.4

  • Autotrophic bacteria and prostists (algae) use carbon dioxide (CO2) and release oxygen (O2) during photosynthesis.
  • Algae are responsible for more than 50% of the O2 that is produced by photosynthesising organisms.

18

7.2

In contrast to the autotrophic bacterium,

Thiobacillus bacteria can also have a

saprophytic mode of nutrition.

 

7.2.1

What is meant by "saprophytic mode of nutrition"?

 

7.2.1

Mode of nutrition where organisms

live on dead organic matter

19

7.2

In contrast to the autotrophic bacterium,

Thiobacillus bacteria can also have a

saprophytic mode of nutrition.

7.2.2

On which trophic level of the food chain will saprophytic bacteria occur?

 

7.2.2

Decomposers

20

7.2.3

Describe the role of saprophytic bacteria in the trophic level mentioned in Question 7.2.2

 

7.2.3

  • Decomposers break down dead organic matter to its building blocks
  • Water (H2O), carbon dioxide (CO2), amonia (NH3) and heat energy are released in the soil, water and air, during decomposition.
  • In this way elements, escpecially carbon (C), nitrogen (N), phosphorus (P) and sulphar (S) are recycled in the environment and are made available for uptake in plants.

21

7.3

Why must chemical detergents not

be used in septic tanks with sewerage?

 

7.3

The chemicals kill the bacteria, and then they cannot decompose the sewage.

22

7.4

Describe how each of the following bacteria play a role in the nitrogen cycle

7.4.1

free-living bacteria

 

7.4.1

The bacteria absorb free nitrogen from the atmosphere

- it is processed in their bodies to form proteins -

when they die, the proteins are converted to nitrates that can be absorbed by the plants.

23

7.4

Describe how each of the following bacteria play a role in the nitrogen cycle

7.4.2

root nodule bacteria

7.4.2

The bacteria bind free nitrogen from the atmosphere and make it available in an accessible form for the leguminous plants on which they grow.

When the leguminous plants are ploughed back into the soil, it increases the fertility of the soil

 

24

7.4

Describe how each of the following bacteria play a role in the nitrogen cycle

7.4.3

nitrifying bacteria

7.4.3

During the decomposition of plant and animal material, ammonia is released.

Nitrite bacteria convert the ammonia to nitrites.

The nitrites are then converted by nitrate bacteria into nitrates

25

7.4

Describe how each of the following bacteria play a role in the nitrogen cycle

7.4.4

denitrifying bacteria

7.4.4

Bacteria that can break down

nitrates,

nitrites and

ammonia

with the release of nitrogen gas into the atmosphere.

26

7.5

 

The bacterium E. coli lives mutualistically in the intestine of humans.

Discuss this statement

7.5

 

Both parties benefit in a mutualistic relationship.

E. coli in human intestines produce vit. K which is necessary for blood clotting and certain B-vitamins.

In exchange for this E. coli is provided with a protected habitat.

27

Question 8

Name FIVE general characteristics of protists

8.

  • have true cell nuclei; therefore eukaruotic
  • some are unicellular; other are multicellular (algae)
  • autotrophic or heterotrophic
  • reproduction mostly asexual; some algae sexual
  • live in almost any environment where water occurs

28

Question 9

Mushrooms, fungi and yeasts are part of a

large group of plant-like organisms containing 

+/- 80 0000 known species.

However, they differ from true plants and thus

belong to their own kingdom.

9.1

To which kindgom do these organisms belong?

 

9.1 

Fungi

29

9.2

 

State the general characteristics of the

Fungi kingdom

9.2

  • Yeasts are unicellular; mushrooms and moulds are multicellular
  • have true nuclei and are eukaryotic
  • have cells walls of chitin
  • consists of a mass of branched filaments or hyphae
  • have no chlorophyll and are therefore heterotrophic (saprophytic/parasatic/mutualistic)
  • reproduction can be asexual or sexual

30

9.3

Name the 3 different hyphae that occur in

Rhizopus (bread mould)

9.3

  • stolons (runners)
  • rhizoids
  • sporangiophores

31

9.4

Rhizopus is a thallus with hyphae that are known as aseptate coenocytes.

What is meant by:

9.4.1 

a thallus

9.4.2

an aspetate coenocyte

9.4.1

No true roots, stems and leaves are distinghuised

 

9.4.2

A cell/part of an organism that has many nuclei in a common cytoplasm, without any cross-walls

32

Question 10

10.1

AIDS is a sexually transmitted disease

caused by a virus.

10.1.1

What does abbreviation AIDS stand for?

10.1.2

What is the name of the viurs that causes AIDS?

 

10.1.1

acquired immune deficiency sundrome

 

 

10.1.2

human immonodeficiency virus

33

10.2

What causes the weakening of the human immune system during an HIV infection?

10.2

The HI-virus infects the immune cells

that initiate the immune response in the

human body (the CD4-cells).

 

The virus multiplies and destroys the CD4-cells

which weakens the immune system.

34

10.3

The effects of an HIV infetion initially include flu-like symptoms. As the immune system weakens, more symptoms appear, including opportunistic infections.

 

10.3.1

What is an opportunistic infection?

 

10.3.1

 

Desease that attacks the body

when the immune system is weak

35

10.3.2

Name any 5 examples of opportunistic infections that occur due to HIV/AIDS

10.3.2

  • respiratory infections
  • lung infection
  • peripheral neuropathy
  • neurological conditions, e.g. epilepsy
  • rare skin cancer
  • lymph cancer
  • tubercolosis (TB)

36

10.4

The mining industry is infamous for the

high rate of HIV infection.

Describe how this affects the

South African economy 

10.4

  • A drastic decrease in the labour force of the mining industry is predicted for the future, which is a huge threat to its productivity.
  • Direct costs associated with HIV/AIDS include the cost of medical care and medication.
  • Indirect costs include
    • time lost due to illness,
    • recruitment and training
    • costs to replace workers, and
    • costs for care of HIV orphans

37

10.5

In the management of HIV/AIDS,

testing is very important.

Discuss this statement.

10.5

  • It is important that a person knows his/her HIV status.
  • If HIV negative (HIV-) then safety measures can be taken to prevent HIV infection.
  • If HIV positive (HIV+), the disease can be controlled by
    • taking correct medication,
    • making lifestyle changes,
    • preventing infection of others
  • Pre- and post-counselling is of great importance when testing is done.

38

10.6

The management of HIV/AIDS depends on

keeping the viral load as low as possible

and the CD4-count as high as possible.

Name 3 ways of treating HIV/AIDS.

10.6

 

  • antiretroviral drugs (ARVs) are used
  • the immune system is strenghtened
  • opportunistic infections are treated

39

10.7

 

Name 4 preventative measures that can prevent/reduce the chance of HIV infection.

10.7

 

  • abstain from sexual intercourse
  • one, faithful, long-term HIV negative sexual partner
  • practice protected, safe sex (use of condom)
  • treatment of other STDs
  • avoid direct contact with blood
    • wear rubber gloves
    • do not share injection needles
  • avoid alcohol and drug use, which can lead ti reckless sexual activities

40

Question 11

 

11.1

What causes TB?

11.1

The bacterium

Mycobacterium tuberculosis

41

11.2

Why is TB considered a poverty-related disease?

11.2

  • In poor communities people generally live together in over-populated areas.
  • Rooms are usually dark and unventilated, which increases chance of infection.
  • People's resistance to the disease is further reduced because of malnutrition and disease like HIV/AIDS

 

42

11.3

How is TB spread?

11.3

 

The bacteria get into the air by an infected person coughing, sneezing, screaming or spitting.

The small particles in the infected drops are then inhaled.

43

11.4

Describe the effect of TB on the human body

11.4

  • When the inhaled TB bacteria enter the lungs, they reproduce and cause infection of the lungs. 
  • If the body's immune system is strong it can fight the infection and prevent the bacteria spreading.
  • However, if the immune system is weak it can lead to active TB, where pneumonia occurs repeatedly and the bacteria spread to other parts of the body.

44

11.5

Name 4 syptoms of TB

11.5

  • a constant cough
  • tiredness and fatigue
  • weight loss
  • night sweats
  • chest pain
  • blood in saliva when coughing

45

11.6

What is included in the

management of TB treatment

11.6

 

Treatment includes an aggressive course of antibiotics that lasts for 6 months

46

11.7

Name 4 ways in which TB can be prevented/reduced

11.7

  • education regarding the spread of TB and the importance of hygenic conditions, sunlight, fresh air and a balanced diet
  • treatment directly after diagnosis - prevents spreading
  • healthcare workers must be informed about the risk of infection
  • immunisation with BCG vaccine

 

47

11.8

The development of drug-resistant TB is largely a result of poorly managed TB care and the incorrect use of anti-TB drugs.

11.8.1

What is multi-drug resistant TB (MDR-TB)

 

11.8.1

It is TB bacteria that do not react to

any medication and

are therefore resistant

to the medication

48

11.8.2

Why is drug-resistant TB

such a serious problem?

11.8.2

 

  • requires long-lasting chemotherapy that is 100 times more expensive than normal treatment
  • very difficult to treat (only 50% successful)

49

11.8.3

What does "incorrect use of anti-TB drugs" mean?

11.8.3

  • patients on treatment start to feel better and do not complete their full 6 month antibiotic course
  • after a while the patient becomes sick and infectious again
  • the same medication is often not effective due to resistance

50

11.9

 

What is the relationship between

TB and HIV/AIDS?

11.9

  • TB & HIV/AIDS are a deadly combination, where the 1 disease accelerates the progression of the other.
  • TB is most common opportunistic infection and is also the cause of death of many HIV/AIDS patients.
  • As the HI-virus multiplies and the immune system becomes weaker, the chances of and HIV+ person developing TB increases
  • TB in an HI+ person accelerates the progression of the virus to the final AIDS stage.

51

Question 12

12.1

What is the genus name of the parasitic protist that causes malaria?

12.1

Plasmodium

52

12.2

Explain how the malaria parasite

is transferred from one organism

to another organism

12.2

  • transmitted by the female Anopheles mosquito
  • mosquito bites an already infected person
  • blood containing parasites is ingested
  • parasites develop further in the body of the mosquito
  • mosquito bites next person
  • parasites in the mosquito's saliva, are injected into the person that is bitten

53

12.3

List the symptoms of malaria that indicate the negative impact it has on the human body

12.3

  • fever
  • headache
  • shivering
  • joint pain
  • vomiting
  • convulsions

54

12.4

Name 5 aspects of the management of malaria

12.4

  • treatment of the disease
  • destruction of vector mosquitoes
  • use of mosquito nets treated with insecticides
  • use of prophylactic medication
  • immunisation/vaccination

55

12.5

Discuss the effect of malaria on the economy of the country, as well as on the family of a sufferer.

12.5

  • Malaria is often associated with poverty, but is also a cause of poverty.
  • The treatment of malaria is expensive and poor people in developing countries cannot afford it.
  • When the breadwinner becomes sick or dies, the consequent loss of income leads to further impoverishment.
  • Similar to HIV/AIDS and TB, malaria is disease that places huge economic burden on the health sector of a country.
  • The costs associated with anti-malaria medication, the maintenance of and the prevention of malaria are very high and most developing countries cannot afford these costs.

56

12.6

Name 2 natural compounds that are traditionally used against malaria

12.6

  • quinine
  • artemisinin

57

Question 13

13.1

Which fungus causes candidiasis?

13.1

Candida albicans

58

13.2

When a person takes antibiotics against a bacterial infection, special precaution needs to be taken against candidiases/vaginal thrush. Why?

13.2

Antibiotics destroy the normal symbiotic bacteria in the large intestine, but no the yeast.

Without any competition from the bacteria, they multiply abnormally fast and spread to the vagina, causing the symptoms of Candidiasis.

59

13.3

Women who are exposed to high levels of stress, eat an unbalanced diet and sleep too little, are more prone to candidiasis.

Explain why this is so.

13.3

  • high stress levels - cortisol (a hormone) is released, which supresses the immune system and increases sugar levels
  • bad diet - too many refined carbohydrates and sugar act as a food source for Candida
  • lack of sleep - this weakens the immune system

60

13.4

People with HIV often get oral thrush.

Why?

13.4

Their immune system is weakend by the HI-virus, so it is unable to inhibit the growth of the Candida fungus 

OR

They probably take antibiotics against other infections which developed as a result of a weakended immune system

61

13.5

Why would the doctor/pharmacist advise a person that is being treated with antibiotics to eat yoghurt with AB cultures?

13.5

The AB cultures are the bacteria in yoghurt that can inhibit the growth of the Candida fungus

 

62

Question 14

Explain what is meant by:

14.1

an immune response

14.1

It is the way an organism protects itself against

  • pathogenic viruses,
  • bacteria
  • protozoa
  • fungi

63

Question 14

Explain what is meant by:

14.2

active acquired immunity (natural)

14.2

This type of immunity is obtained without immunisation.

Direct contact with pathogens stimulates the immune system to produce antibodies.

64

Question 14

Explain what is meant by:

14.3

passive acquired immunity (natural)

14.3

This type of immunity is obtained without immunisation.

Antibodies are transferred from mother to foetus through the placenta, as well as from mother's milk to baby

65

Question 14

Explain what is meant by:

14.4

inoculation/immunisation

14.4

The administration of a vaccine

(dead or weakend form of pathogen that causes the disease)

by means of an injection or orally

to develop immunity against a disease