U04 Reproduction

ESSENTIAL NATURAL SCIENCE 2Unit 4

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CONTENTS

RESOURCES

Reproduction



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CONTENTS

Reproduction

Types

Advantages and disadvantages

Asexual reproduction

Vegetative Spore formationArtificial

Fertilisation

ExternalInternal

Sexual reproduction

Sexual reproductionMixed reproduction

Reproduction in animals

Reproduction in plants

Embryonic development

ViviparousOviparousOvoviparous

Post-embryonic development

DirectIndirect

Sexual reproduction

Sexual reproduction

Stages

PollinationFertilisationSeed germination

Hands on

Make a detailed drawing

Life cycle

Life cycle of a plant

Life cycle

Life cycle of a bird


GemmationFragmentation

REPRODUCTION



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RESOURCES

Types of reproduction


FragmentationGemmation Sexual reproductionin animals

Mixed reproduction

External fertilisation

Internal fertilisation

Oviparous development

Viviparous development

Post-embryonic development: direct

The life cycle of a bird

Ovoviparous development

Post-embryonic development: indirect

Spore formation

The life cycle of plants

Artificial asexual reproduction

Vegetative reproduction

Sexual reproductionin plants

Pollination

Seed germinationFertilisation Make a detailed drawing

Links

Animal reproduction



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Unicellular oganismsASEXUAL REPRODUCTION

• Only one parent

• New genetically identical living beings are produced.

Some animals

Some plants


ProtozoaFungi

AlgaeNEXT



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SEXUAL REPRODUCTION

• Two parents: a male and a female

• Descendants have genetic material from both parents.

Multicellular oganisms



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Advantages• requires only one parent

• faster and easier

• rapid population growth

• no travel is necessary

Disadvantages

• no genetic diversity

• difficulty in adapting to environmental changes

clone

Asexual reproductionNEXT



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Advantages

• genetic diversity in species

• ability to adapt to environmental changes

Disadvantages• requires two parents

• requires time and energy to find a mate and reproduce

• requires travel

Sexual reproduction



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Gemmation (budding)


Fresh water hydra

bud

The bud separates from the parent and develops into a new individual.

NEXT



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Gemmation (budding)

Colony gemmation

Coral

Buds remain attached and form a colony.



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Fragmentation

Regeneration

regenerated arms

StarfishNEXT



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Fragmentation

new organisms

fragments regenerate

parent

Planaria worm




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Snails

Sexual reproduction in animals

Hhermaphrodites have both male and female gonads.

NEXT



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ovum

spermatozoa

Sexual reproduction in animals

Unisexual animals have only one type of gonad.male (♂)

female(♀)

gonads(testicles)

gonads(ovaries)



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Mixed reproduction

Cnidaria

sexual reproduction

asexual reproduction

larva

polyps

adult jellyfish or medusa



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male(♂)

female(♀)

Fusion of the gametes occurs outside the female body.

developing embryos

ova

spermatozoa

External fertilisation

Life cycle with external fertilisation



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Internal fertilisation

Life cycle with internal fertilisation

male (♂)

female (♀)

ovum

spermatozoa

zygote

Fusion of the gametes occurs inside the female body.



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Viviparous development

Mammals


The embryo develops inside the female body.

placenta

umbilical cord

uterus

embryo



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embryo

Fish

Birds


Reptiles

Reptile or bird egg

shellchalaza

albumin

yolk

germinal discshell

membrane

Oviparous development

The embryo develops inside an egg, mostly outside the female body.

hatching



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shark


ray

snakelizard

The embryo develops inside an egg in the female body.

embryo

Ovoviparousdevelopment



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Life cycle of a bird

embryonic development

After fertilisation, the embryo begins to develop

inside the egg.

The egg is laid in a nest.

The embryo continues to develop during incubation.

Hatching

The male and female bird mate.

The new being leaves the egg.



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Some arthropods

Oviparous birds

Viviparous mammals

Post-embryonic development: direct

Oviparous reptiles



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Simple metamorphosis

larvaeggs

adult

continuous transformation

(moulting)

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Complex metamorphosis

pupa(dormant stage)

larva

eggs

adult



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FLOWERING PLANTS

NON-FLOWERING

PLANTS

Angiosperms

Gymnosperms

Mosses

Ferns

VISIBLE PART

gametophyte

VISIBLE PART

sporophyte

NEXT

VISIBLE PART

sporophyte

gametophyte



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sporophyte

gametophyte

germination

sporangium

spores

frond

fertilisation♀♂

male gametophyte

♂

female gametophyte

♀

prothallus


The life cycle of mosses The life cycle of ferns

capsule

sporophyte

spores

germination

gametophyte

male gametophyte

female gametophyte

fertilisation

♂♀

♀ ♂



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fern

Spore formation

spores

moss

spores

spores

mushroom

FUNGI ARE NOT PLANTS.



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Vegetative reproduction

white clover

stolon

bud

Stolons Bulbs

Stem tubers

potato

oniongarlic



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Cuttings

Artificial asexual reproduction in plants

Grafting

Layering

Artificial methods



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Sexual reproduction in plants

FLOWER

gametophyte

reproductive organs

gametes

anther

pollen grains

anther

filamentstamen

sepals (calyx)

stigma

style

ovary

ovules

pistil

petals(corolla)



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Pollination

Self-pollination

Cross- pollination

pollen

pollen

Wind pollination

Insect pollination



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Fertilisation in plants

Pollen grains land and a pollen tube develops.1

pollen grains

The ovule (female gamete) is fertilised and a zygote is formed.

2 ovule

pollen tube

male gamete embryo

albumin

seed

cotyledons

The ovary becomes the

fruit and the ovule becomes a seed.

3

The seed germinates and an embryo develops.4



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cotyledons

radicle

plumule

bud

Seed germination

OXYGENTEMPERATURE

MOISTURE

seed

water



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Make a detailed drawing: The flower

sepal

ovary

style

petalstigma

anther Prepare the slide Remove some petals.

Place the flower on a glass.

Tape the flower to the transparency. Cut the transparency into a square.

Place it on a slide frame.

Project the image.Insert the slide into the projector.

Project the image onto the paper.

Move the projector in close so the

entire image fits on the paper.

Draw over the projected image.

Complete the drawing Add the names of each part of the flower.



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Links

Animal reproduction

http://www.saburchill.com/chapters/chap0031.html

Plant Reproduction Tutorialhttp://www.skoool.ie/content/skoool_learning/junior/lessons/science/plant_reproduction/flash/h-frame-ie.htm

Growing plants http://www.bbc.co.uk/scotland/education/bitesize/standard/biology/world_of_plants/growing_plants_rev1.shtml

How plants reproducehttp://www.emc.maricopa.edu/faculty/farabee/BIOBK/BioBookflowers.html

Flowers and reproduction

http://www.saburchill.com/chapters/chap0041.html

Technology

U04 Reproduction