Second Semester PowerPoint Presentation on the flowering plants, the largest organisms of the plant kingdom. This was presented by Group 10.

1. Angiosperms (Flowering Plants)
Presenters:
Group ten (10)
Bota 104, Mother Patern
college of Health Sciences May 13, 2019

2. Lesson Outline
• An overview of Angiosperms
 Selective advantage of flowering plants which has
led to their success
• General Characteristics of Flowering plants
• Reproduction in Angiosperms
• Classification of Angiosperms
• Ecological and Economic Importance

3. Lesson Objectives
By the end of this presentation, learners will be able to:
1. Define, and discuss the term angiosperm
2. Discuss the form of reproduction in these organisms
3. Classify angiosperms
4. Discuss the impacts of these organisms
• Economically and ecologically

4. Overview of Angiosperms
• Angiosperms are plants that produce flowers, fruits and seed; and have
their ovules enclosed in an ovary
• It comes from two Greek words ‘angion’ (container) and ‘Sperma’ (seed)
• The largest and most diverse group in the kingdom Plantae, with 68
orders, 416 families, approximately 13,164 known genera and about
400,000 species, and make up about 90% of all plant species on earth
• Considered a group, at the level called Anthophyta. Examples include:
Montsechia Vidalii, sunflower, Wolffia etc.

5. Overview Cont’d
Sunflower Wolffia

6. Overview Cont’d
Selective advantages of flowering plants which
have led to their success
• Angiosperms’ use of flowers to reproduce
made them more reproductively successful
• The pollination of flowers by animals or bees
in exchange for nectar made angiosperms
more reproductively successful.
• Angiosperms also began to encase their
seeds in fruits, which provide both extra
nourishment and protection for their
offspring

7. Overview cont’d
• Produce flowers and fruits to aid
in seed dispersal
• Can produce spores which are
more stable than seeds from
gymnosperms
• Most importantly, they have
vessels that can escalate their
growth

8. Overview Cont’d
• Some differences between angiosperms and gymnosperms
Characteristics Angiosperms Gymnosperms
Definition Seed-producing flowering
plants whose seeds are
enclosed with an ovary
Seed-producing nonflowering
plants whose seeds are naked
Seeds Enclosed inside an ovary,
usually in a fruit
Bare, not enclosed; found on
scales, leaves, or as cones
Life cycle Seasonal(die during autumn or
fall)
Ever green
Leaves flat Scale-like; needle-like
Reproduction Mostly rely on animals Mostly rely on wind
Uses Medication, food, clothing,
etc.
Paper, timber, etc.

9. Overview Cont’d
• Some similarities between angiosperms and gymnosperms
 Both are capable of producing pollen for fertilization, which is
siphonogamous, i.e., through a pollen tube
 The sporophyte of both of these varieties is differentiated into
root, stem and leaf
 The ovules of both angiosperms and gymnosperms develop
into seeds
 The most distinct similarity is the reduced gametophyte phase
of both plants

10. Evolution of Angiosperms
• Angiosperms appeared on earth during
the Cretaceous period.
• Their common ancestor is the
gymnosperms
• The origin and spread of angiosperms
was described as “abominable
mystery” by Charles Darwin
• Gnetophytes and Bennettitales are the
groups of gymnosperms most similar to
angiosperms

11. General Characteristics - Habitat
• Angiosperms are mostly terrestrial
• A few species are aquatic
Thalassia
Zostera

12. General Characteristic Cont’d
Other forms of habitat include:
• Freshwater e.g. Wolffia, Lemna, etc.
• Mesophytes e.g. Sunflower;
mulberry
• Xerophytes e.g. Alhagi, Capparis, etc.
• Succulents e.g. Euphorbia, Opuntia,
etc..

13. General Characteristics Cont’d
• Lithophytes
• Halophytes e.g. Suaeda
• Psammophytes e.g.
Yellow brown Rape
• Some may be found in
marshy habitats e.g.
Rhizophora

14. General Characteristics - Habits
• The habits of a flowering plant can be determined by its height, duration
and nature of stems
• They are of three main types: Wheat
1. Herbs e.g. wheat
2. Shrubs e.g. Jasmine
3. Trees e.g. Dalbergia
Dalbergia
Jasmine

15. General Characteristics Cont’d
• Habits
• Other forms include:
 Trailers e.g. Tribulus
 Creepers e.g. Grass
 Twiners e.g. Ipomoea
 Climbers e.g. grape vine
 Lianas e.g. hiptage
 Epiphytes e.g. Vanda

16. General Characteristics - Morphology
• The branch of biology that deals with the study of the form,
size, and structure of an organism
• Morphologically, angiosperms’ bodies are divided into two
main systems:
1. Root System
2. Shoot System

17. General Characteristics Cont’d

18. General characteristics cont’d
Types of roots
• In flowering plants, there are three main types of roots, which include:
1. Tap roots
2. Fibrous roots
3. Adventitious roots
Adventitious roots

19. General Characteristics Cont’d
Venation in flowering plants
• The pattern of veins on a leaf
• There are two main types:
1. Parallel venation
2. Reticulate venation Parallel venation
Reticulate venation

20. General Characteristics - Nutrition
• Angiosperms are mostly autotrophic plants, though a few are
heterotrophic
• The heterotrophic angiosperms are of three types:
1. Saprophytes
2. Parasites
3. Insectivores
Arceuthobium americanum

21. General Characteristics Cont’d
• Insectivorous Angiosperms
Ventricosa Nepenthes Venus Flytrap – Da

22. General Characteristics Cont’d
Bacterial leaf symbiosis
• a unique and intimate interaction between bacteria and
flowering plants, in which endosymbionts are organized in
specialized leaf structure
• The Burkholderia endosymbionts can be found in 54 plant
species including: Ardisia, Pavetta, Psychotria; Sericanthe
• This interaction can be termed as obligate

23. General Characteristics Cont’d
• Bacterial Leaf Symbiosis

24. General Characteristics - Germination
• Three types of germination are
seen in angiosperms
1. Hypogeal Germination
2. Epigeal Germination
3. Viviparous Germination
(Vivipary)

25. General Characteristics - Movement
• Angiosperms exhibit what is called movement of curvature
• Movement restricted only to bending or movement of some
body parts
• It is of two types:
1. Autonomic (spontaneous) movement of curvature
a) Autonomic movement of variation
b) Autonomic movement of growth
2. Paratonic (induced) movement of curvature
a) paratonic movement of growth
b) paratonic movement of variation

26. General Characteristics Cont’d
• Movements in angiosperms

27. Reproduction in angiosperms – Sexual
Reproduction
• This involves the production of male and female gametes
• It is the transfer of the male gamete to the female ovule through the
process of pollination
• Unlike bryophytes and seedless vascular plants, angiosperms and
gymnosperms have a larger, photosynthetic and dominant sporophyte
• However, the ovules of flowering plants develop into fruits inside the
ovaries

28. Reproduction Cont’d
Sporophyte and gametophyte stage
compared to gymnosperms
• In angiosperms, the alternation of
generation found in gymnosperms is more
modified and gametophytes are reduced
size and cellular number
• The immature and mature
microgametophytes in angiosperms and
gymnosperms
• The megagametophyte is reduced to much
greater extent
• The presence of Archegonia

29. Reproduction Cont’d
Description of a typical flower
• A typical flower has four main parts or
whorl which include:
1. Calyx
2. Corolla
3. Androecium
4. Gynoecium

30. Reproduction Cont’d
• The calyx is composed of green leafy structures known as sepals. It
protects the inner part of the flower, and is the outer most whorl
• The corolla is comprised of petals which are usually brightly
colored. Its function is to attract insects to the flower
• Together, the calyx and corolla are known as the perianth.
• The number of sepals and petals varies depending on the plant;
whether it is a monocot or a dicot.

31. Reproduction cont’d
• The androecium which is the third part of the flower contains the male
reproductive structure.
• It has stamens with anthers that contain the microsporangia.
• The gynoecium is the inner most part of the flower.
• It contains the female reproductive components.
• The carpel is the individual unit of the gynoecium that has a stigma,
style and ovary

32. Reproduction cont’d

33. Reproduction cont’d
• A flower may be a complete flower or an incomplete flower
• There are two types of flowers in plants
I. The bisexual flower, which contains both the androecium and the
gynoecium. They are complete flowers and can also be referred to
as androgynous or hermaphrodite
II. The unisexual flowers contain the androecium and the
gynoecium on separate flowers. A unisexual flower is an
incomplete flower and can be termed as staminate or carpellate
flower.

34. Reproduction cont’d
• Unisexual flowers are of two types, namely;
a. Monoecious – both staminate and carpellate flowers
borne on the same plant
b. Dioecious – the staminate and carpellate flowers are borne
on separate plants

35. Reproduction cont’d
Inferior and superior flower
• A flower can also occur as inferior or superior

36. Reproduction cont’d
Development of the ovum in the ovary
• In angiosperms, the ovule is the structure that gives rise to and
contains the female reproductive cells
• It has three major parts:
1. The integument
2. The nucellus
3. The female gametophyte

37. Reproduction cont’d
• The integument is a protective cell layer surrounding the ovule. It is
divided into an outer and inner integument. They develop into seed
coat when the ovule matures at fertilization
• The nucellus forms part of the inner structure of the ovule, forming
a layer of diploid (sporophytic) cells inside the integument.
• The female gametophyte is known as the megagametophyte and
can also be termed as the embryo sac in angiosperms.

38. Reproduction cont’d

39. Reproduction cont’d
Development of pollen grain in the
anther
• The male gametophyte develops and
reaches maturity in an immature anther
• In a plant’s male reproductive organ,
development of pollen takes place in a
structure called the microsporangium
• The sporangia, which are usually bi-lobed,
are pollen sacs in which the microspores
develop into pollen grain.
• These are all found in the anther, which is
at the end of the stamen (the long
filaments that support the anther)

40. Reproduction cont’d

41. Reproduction cont’d

42. Reproduction in Angiosperms - Pollination
• The process by which pollen grains are transferred from the
anther to the stigma of flowers
• Pollination can be achieved in either of the two processes:
 Autogamy (self-pollination)
 Allogamy (cross pollination)

43. Reproduction cont’d
Inbreeding Devices
• These are conditions that favor self-
pollination. They include the following:
 Bisexuality e.g. Lilly, Rose, Tulip
 Homosexuality
 Cleistogamy e.g. peas, peanuts,
etc.

44. Reproduction cont’d
Outbreeding Devices
• This refers to the conditions that favor cross pollination, and
include the following:
 Unisexuality e.g. Casta, Papaya, etc.
 Dichogamy e.g. Ivy, Plantain, etc.
 Self sterility (incompatibility) e.g. tobacco, potato
 Herkogamy e.g. pansy
 Heterostyly e.g. primula, Jasmine

45. Reproduction cont’d

46. Reproduction cont’d

47. Reproduction cont’d
Agents of pollination
• Abiotic agents
 Anemophily e.g. grasses, palms, coconut, etc.
 Hydrophily e.g. Zostera, Hydrilla, Vallieneria

48. Reproduction cont’d
• Biotic agents (zoophily)
 Entomophily e.g. Sunflower, roses,
 Myrmecophily e.g. Amorphophallus,
insects, yucca &pronuba moth
 Ornithophily e.g. Bombax, erythrina
 Chiropterophily e.g. kigellia,
anthocephalous, etc.
 Malacophily e.g. Lemna, ariseema,

49. Reproduction cont’d
• Pollination can also occur by the following:
• Lemur, Gecko lizard; Rodents

50. Life Cycle of a Typical Flowering Plant
• Like gymnosperms, the lifecycle of a typical angiosperm is
heterosporous
• They carry out a unique process known as double
fertilization
• Before this process can occur, the ovule has to undergo
some changes

51. Life Cycle Cont’d

52. Life Span of a Flowering Plant
• Life span is the time taken by an organism
to complete its lifecycle
• On the basis of their lifespan, plants are of
four types, which include:
 Ephemerals e.g. Anagalis arvensis
 Annuals e.g. maize, wheat, etc.
 Biennials e.g. henbane, Radish, carrot,
etc.
 Perennials e.g. Bamboos, agave,
cotton, etc.

53. Classification of angiosperms
• The phylum Anthophyta has been historically and
typically divided into two main classes:
1. Monocot
2. Dicots
However, recent molecular studies have revealed that the
phylum consists of four main groups:
1. Basal angiosperms
2. Magnoliids
3. Monocots
4. Eudicots

54. Classification cont’d
Basal Angiosperms
• Consist of several families of woody shrubs and
herbs
• They are a broad group of the most primitive
angiosperms, and they constitute about 0.5% of
all living angiosperm species.
• The extinct ancestors of basal angiosperms are
thought to include the first angiosperms which
gave rise to all others.
• Are mostly woody plants
• Flowers are insect pollinated, bisexual and
radially symmetrical

55. Classification cont’d
Magnoliids
• Magnoliids are a monophyletic group
of about 20 families
• Along with basal angiosperms, they
are some times loosely referred to as
Paleoherbs (ancient herbs)
• The magnoliids constitute about 2.5%
of living angiosperms species
• Living groups of magnoliids include
both woody and herbaceous plants

56. Classification cont’d
Magnoliids
• They have spiral arrangement of flower parts
• Their carpels are sealed by cells
• Stigma sometimes extends down the carpel
• Pollen grain with a single opening
• Netted leaves venation
• Tap root system
• Two cotyledons

57. Classification cont’d
Monocots
• Plants with two cotyledons (seed leaves)
• the monocots have pollen grain with one
opening
• Their leaves have parallel venation
• They have scattered vascular bundles
• Fibrous root system
• Carpels sealed by cells
• Whorled arrangement of floral parts

58. Classification cont’d
• Dicots
• The dicotyledons are one of the
two groups into which all the
flowering plants or angiosperms
were formerly divided
• They are also known as dicotyls
• The name refers to one of the
typical characteristics of the group,
i.e. the seed has two embryonic
leaves
• There were about 200,000 known
species within this group
Structure of a dicot seed

59. Classification cont’d
Dicots
• Dicots roots generally have a distinct tap
root with a few major lateral branches
• The roots are seldom fibrous as they are
in monocots
• the vascular bundles (xylem and phloem)
are arranged in a ring closed to the
outside of the stems

60. Classification cont’d
Eudicots
• Eudicots are a hugely diverse and abundant
group of flowering plants
• Commonly known as “true dicots”.
• They constitute about 69% of angiosperm
species
• This group contains 150,000 species and
approximately 319 families

61. Classification cont’d
Eudicots
• they have net-veined leaves (venation)
• Flower parts usually in multiples of four or
five
• Contain embryo with two cotyledons
• Vascular bundles arranged in a ring in
stem
• Consist of tricolpate pollen

62. Classification cont’d
Eudicots:
• The class is divided into two groups namely;
 Basal eudicots
 Ranunculales
 Protales
 Core eudicots
 Rosids
 Asterids
 Carophyllids

63. Economic and Ecological Importance
• Human source of food,
nutrients, income, etc.
• Used as food and habitat for
wildlife
• Used for decoration

64. Economic and Ecological Importance
• Angiosperms are also used in the
production of medicine
• Some plants that can be used for
medical purposes are:
 Sunflower – (controls high blood
pressure and ensures healthy skin)
 Milk thistle - (used to treat liver
problems and treatment of
cancer)
 Marigold - (used in treating
immune response and stomach
pains)

65. Summary
• Angiosperms are the most dominant form of plant in most terrestrial
ecosystem, comprising about 80% of all plant species.
• Most crops and ornamental plants are angiosperms.
• Their success comes from two innovative structures that protect
reproduction from variability in the environment: the flower and the fruit.
• The plant body can be differentiated into roots, stems and leaves, divided
into the root and shoot system
• Roots, stems, and leaves are vegetative organs, whereas flowers, fruits and
seeds are reproductive organs.
• Flowering plants mode of nutrition may be autotrophic, heterotrophic-
parasitic, saprophytic, or insectivorous.
• Germination in angiosperms may be epigeal, hypogeal, or viviparous.
• Their movement involves moving a body part primarily or permanently in
response to externally or internal stimulus.
• Angiosperms are economically important in decoration, papers production,
medication, etc.

66. Reference
• Nabor, Murray W., INTRODUCTION TO BOTANY, Copyright 2004
Pearson Education, Inc., publishing as Benjamin Cummings, 1301
Sansome St., San Francisco, CA 94111
• https://www.en.m.wikipedia.org/wiki/floweringplantsquizlet.com
• https://www.evoluntionaryedges.weebly.com/floweringplants
• https://science.jrank.org/pages/2761
• http://www.biologydiscussion.com/seed/germination/seed-
germination-types-with-diagram/15789
• http://leavingbio.net/structure-flowering-plants/
• https://www.cropsreview.com/plant-root-system.html
• https://biodifferences.com/difference-between-parallel-and-
reticulate-venation.html
• http://www.biologydiscussion.com/angiosperms/angiosperms-size-
habit-and-life-span-plants/70030
• https://en.m.wikipedia.orginal.org

67. “How you respond to the challenge in
the second half will determine what
you become after the game, whether
you are a winner or a loser”
Lou Holtz
“The power to become a winner or to
remain a loser lies within you, so
choose what you want to be”
Martin M. N. Forkaph

68. Group Ten (10) Members
Abigail D. Telyon Deborah W. Nurse
Mary A. Tajudee Richlyne G. Kermue
Gonee O. Mulbah Martin M. N. Forkpah