Grade 11: Life Science - Plant biodiversity

1. KGOTSO SEROKA
KLMMETSE@GMAIL.COM
Grade 11 : Life Science

3. What do we expect from a student!
 Cooperate with one another.
 Ask questions.
 Seek for help where necessary.
 Attend all classes - Write notes.
 Short test every session.
 Term tests.

4. Suggestions?

8. Biodiversity and Classification of Microorganisms

9. Biodiversity
 Virus
 Bacteria
 Protista
 Fungi

13. Diseases caused by Microorganisms
Viruses (rabies, HIV/AIDS, influenza)
Bacteria (blight, cholera, tuberculosis, anthrax)
Protists (malaria)
Fungi (rusts, thrush, ringworm, athlete’s foot).

14. Symbiotic relationship
 Nitrogen fixing bacteria in plants.
 E.Coli in the human intestine

17. Homework
Name groups of microorganisms and give examples for each.
Diseases caused by microorganisms animals and plants.
The use of microorganisms.

18. Basic Structure
Virus
• Accellular
• Different shapes.
• Parasitic
• Replicate itself in a host.

21. Bacteria
 Prokaryote – do not contain a nuclear membrane.
 Has three shapes : Bacillus (rod shaped) , Coccus (spherical) and Spirillium (spiral
shaped).
 Three ways of attaining energy – photosynthesis, chemosynthesis, heterotrophic
 Reproduce through binary fission.

22. FUNGI

23.  Cell walls are made up of Chitin
 Consists of slender thread-like structures called hyphae

25. Fungi are eukaryotes
Unicellular (yeast) or multicellular
Replicate both asexually and sexually
Obtain FOOD from whatever substrate they
grow on.
Heterotrophic – mostly are saprobes- feed on
dead matter.

26. Protista

28. Animal-like protist – heterotrophic

29. Plant-like protists – autrophic

30. Fungi-like protists – heterotrophic/ decomposers

33. 1. One difference between B and F (2)
2. The patient is allergic to Antibiotic B.
 Which antibiotic should the patient be given? (1)
 Explain your answer? (2)
3.The bacteria seems to be
resistant to two of these antibiotics.
 Name them? (2)
 Explain? (2)
3. The patient was given a 5 day
course of antibiotics.
 Explain why is important to
finish your course of
antibiotics, even if you feel
better? (3)

34. Micro-organisms and their role in
maintaining a healthy
environment.

35. Role of Macro-organisms
Viruses
 Control many ecological processes, such as nutrient
cycling, bacterial and algal biodiversity and algal bloom
control.
 Diseases control the number of dominant species in the
environment.

36. Bacteria:
 Bacteria keep the surface of the Earth clear of dead bodies
and waste matter through decomposition.
 They break down dead organic matter and return nutrients to
the ecosystem.
They create humus in soil, which improves the quality and
water-holding capacity of the soil.
 Converts free nitrogen into ammonia then into amino acids,
used by plants to synthesise proteins.

37.  Many plans have developed a
mutualistic symbiotic relationship
with nitrogen-fixing bacteria.
These bacteria are found in nodules
on their roots.
The bacteria change this free nitrogen
into ammonia and amino acids,
which plants can absorb and use
for growth and the synthesis of proteins
and nucleic acids.

38. The Escherichia coli bacteria have developed mutualistic
symbiotic relationship with humans.
They live inside the large intestine of humans.
This environment protects the bacteria, provides them with a
good supply of food and allows the bacteria to grow and
reproduce safely in large numbers.
 In return, the bacteria provide the human body with extra
vitamins (biotin and vitamin K), which assist in the absorption of
nutrients.

39.  Bacteria are also found in the stomach of cows and sheep.
 They secrete an enzyme called cellulase, which breaks down
or digests the cellulose in the plants that the animals eat.
 The cellulose is broken down into simpler sugars, which the
cells can use for energy.
 Beneficial bacteria such as intestinal flora are often referred to
as probiotics.

40. PROTISTA
 Protista- Algae are important in aquatic environments
because they produce food for the rest of the
ecosystem.
 They produce oxygen during photosynthesis, which is
supplied to aquatic organisms.

41. Many algae are also used as a source of food for
people –particularly in eastern cultures.
 Saprophytic fungi decompose dead organic matter and
make nutrients available for new plant life.
 Larger algae such as kelp provide shelter and habitat
for fish and aquatic invertebrates.

42. They use organic compounds to obtain energy and
create various by-products.
 For example, yeast cells turn sugar into
carbon dioxide and alcohol during
fermentation.
Fungi

43.  Mushrooms are a food source for many animals.
 Other fungi are used in environmental
biotechnology in the clean-up of chemical
pollutants such as oil or detergents.

44.  Some fungi form symbiotic relationships with
other plants.
 Mycorrhiza fungi live on the roots of some plants
and act as root hairs for the plants,
 Allowing them to get nutrients from
the soil.

49. rhizoidsMycorrhiza fungi live
sporangium
Hyphae
rhizoids
Asexual and sexual
1. Decomposers
2. Food source
3. Mycorrhiza fungi – nutrient in plants

50. 1.List the similarities between viruses and bacteria
2.List the differences between viruses and bacteria
3.Why do most scientists say that viruses are not living organisms?
4.Explain why the relationship between the bacteria in the root nodules of
legumes and the plant is a mutualistic relationship.
5.Why do plants need nitrogen?
6.Nitrogen gas is unusable to most plants. Name the form of nitrogen that is
usable by plants.
7.Explain why the relationship between E. coli and humans is considered a
mutualistic relationship.
8.What is a saprophyte?
9.What is the importance of saprophytic bacteria and fungi?
10.What is the importance of nitrogen-fixing bacteria in the environment?
Class test

53. Memorandum: Class test 1

54. Memorandum:
B
D

55. A
A

56. B

57. A

58. ANTBIOTICS
MYCELIUM
Mutual Relationship
Antigen
Coccus/cocci

59. Pathogens
Prokaryotes
Antibodies
Bacillus / bacilliform
Immune Response
Saprophyte

60. Eukaryotes
Flagella

61. Unicellular and acellular

62. Protista and Fungi

63. Specific and non specific immunity

64. Heterotrophs and Autotrophs

65. Antigens and Antibodies

66. The effect and management of
diseases caused by
microorganisms.

67. Virus:
 Rabies
 It is caused by a rabies virus.
 Virus is passed from one host to another in saliva.
 Symptoms are fever and pain at the wound site

68. Management of rabies:
There is no specific treatment for the disease.
 Effective treatment (by immunoglobulin and vaccination) after
exposure to rabies can prevent the disease from starting.
 Dogs and cats can be vaccinated to prevent rabies.

69. BACTERIA:
 Cholera:
 Cholera is an infection of the small intestine that is caused by the bacterium Vibrio
cholerae.
 The bacterium Is transmitted when drinking water or food contaminated with the
faeces from the diarrhoea of an infected person.
 Cholera is found in the area where people do not have access to clean drinking
water.

70. Symptoms of cholera:
 Watery diarrhoea and vomiting

71. Management of cholera:
 People suffering from cholera are treated with fluids and
electrolyte replacement
 Prevention is the best approach to managing cholera
 Spread of cholera can be stopped/prevented by drinking clean
water.

73. Protista:
Malaria:
 There are four species of protists that cause malaria in human:
1. Plasmodium vivax,
2. Plasmodium falciparum,
3. Plasmodium ovale
4. Plasmodium malariae
 The female anopheles mosquito is the vector responsible for
transmission of malaria to humans.

74. Signs and symptoms of malaria
Affected person has a fever and muscles aches,
and feels tired.
Flu-like symptoms.

75. Management of malaria:
 Prevention is the best way to manage malaria (avoid being bitten)
 Take anti-malarial prophylaxis.
 Uncomplicated malaria is treated with oral quinine and antibiotics.
 Severe malaria is treated with intravenous(INJECTION) quinine.

78. Biodiversity of Plants

79. In this lesson we:
 Main characters/differences/similarities of plants.
 Reproduction of plants.
 Significance of seeds.

80. Biodiversity of Plants
Kingdom Plantae is classified into:
 Bryophyta: mosses and liverworts
 Pteridophyta: ferns
 Gymnosperms: cone plants (yellowwoods)
 Angiosperms: flowering plants.

82. Haploid [n]: is the term used when a cell has half the usual number of
chromosomes.
Diploid [2n]: containing two complete sets of chromosomes, one from each
parent.
Gametophyte: the gamete-producing phase.
Sporophyte: spore-producing phase.
Rhizoids: root hair on the underside of the thallus in some lower plants
(bryophytes).
Important terms:

83. Bryophytes
(Small flowerless plants that typically grow in dense green
clumps or mats, often in damp or shady locations)
Example. Moss plants

84. Pteridophyte
A flowerless vascular green plant of the division
Pteridophyte, which comprises the ferns and their
relatives.

85. Gymnosperms
Have exposed or naked seeds that are not found
in an ovary.

86. Angiosperms
Plants that have seeds enclosed in an ovary.

87. Bryophytes
Not have specialized true leaves, stems and roots.
They do not have vascular tissue (xylem and
phloem).
 Produce spores, not seeds.
 The plant body is known as a thallus and the
roots-like structures are called rhizoids.

88. Mature
Gametophyte
Fertilization
Sperm [n]
Egg [n]
Transported by water
Zygote [2n]
Sporophyte
[2n]
Spores [2n]
produced.
Spores [n]
Meiosis occures

89. Pteridophyte
 Have true leaves, stems and roots.
 Have vascular tissue (Xylem and phloem).
 Leaves are compound.
 Stems form rhizomes.
 Produce spores, not seeds.

90. Mature
sporophyte (2n)
Meiosis
Spore mother cells [2n]
Spores [n]
Mature
Gametophyte
[n]
Fertilization
Egg [n]
Sperm [n]
Zygote [2n]

91. Gymnosperms
 Have exposed seeds that are not found in an ovary.
 Well developed vascular system (Xylem and Phloem) and
organ systems.
 Produce naked seeds in cones.
 Have tough leaves that are adapted for dry conditions.

92. Female Cone
Male Cone

94. Angiosperms
Have flowers, roots, stems and leaves.
Have a well developed vascular system
(Xylem and Phloem).
Most are autotrophs, few are parasitic
and saprophytes.

95.  The dominant generation in angiosperms is the diploid
[2n] sporophytes generation.
 Angiosperms and insects have evolved close pollination
partnership relationship over years.
 Many animals depend on flowering plants for food and in
return, these animals disperse their fruit and seeds.
 Protect their seeds inside chambers at the center of a
flower; the walls of the chamber later develop into a fruit.

96. DEPENDENCY ON WATER FOR REPRODUCTION
 Decreasing dependency on water for
reproduction from bryophytes to angiosperms.

 Bryophytes – not evolved for a terrestrial
environment because:
 No cuticle, support and strengthening
tissue.
 Sperm totally depended on water; to
swim to egg.

97. Pteridophytes – more evolved than
bryophytes but still not totally terrestrial
because:
 Tissue have cuticle to protect from desiccation.
 Vascular system to conduct water and minerals.
 But still dependent on water for gamete transfer.

98. Spermatophytes (angiosperms and
gymnosperms) evolved for a true terrestrial
environment because:
 Tissue have cuticle to protect from desiccation.
 Vascular system to conduct water and minerals.
 Embryo now protected from desiccation by being
enclosed in a seed.
 Pollen grains to protect potential sperm from drying out.