Transcript Lesson 2B - Metamorphosis

INTRODUCTION
Science 3001
Science II: Earth & Life Sciences I
Mr. Kishore Lal
Living Things
Lesson 2B - Complete and Incomplete
Metamorphosis
Complete and Incomplete Metamorphosis
What is metamorphosis?
• Metamorphosis means "change".
• Metamorphosis refers to the way form changes as certain
organisms are born, develop, grow, and change.
What’s the difference?
Two Types of Metamorphosis
• Incomplete Metamorphosis - has THREE stages
• Complete Metamorphosis - has FOUR stages.
Complete and Incomplete Metamorphosis
Incomplete Metamorphosis
- 3 Stages
• Egg
• Nymph
• Adult
Eggs
• A female insect lays
eggs.
• These eggs are often
covered by an egg case
which protects the eggs
and holds them together.
Complete and Incomplete Metamorphosis
Nymph
• The eggs hatch into
nymphs.
• Nymphs looks like small
adults, but usually don't
have wings.
• Insect nymphs eat the
same food as the adult.
• Nymphs shed or molt
their exoskeletons
(outer casings made up
of a hard substance
(called chitin) and replace them with larger ones several
times as they grow.
• Most nymphs molt 4-8 times.
Complete and Incomplete Metamorphosis
Adult
• The insects stop molting
when they reach their
adult size.
• By this time, they have
also grown wings.
Insects with Incomplete
Metamorphosis…
• Praying Mantis
• Dragon fly
• Water bug
• Cockroach
• Grasshoppers
• Aphids
Complete and Incomplete Metamorphosis
Complete Metamorphosis 4 Stages
•
•
•
•
Eggs
Egg
Larva
Pupa
Adult
• A female insect lays
eggs.
• These eggs are often
covered by an egg case
which protects the eggs
and holds them together.
Complete and Incomplete Metamorphosis
Larva
• Larva hatch from the
eggs.
• They do not look like
adult insects.
• They usually have a
worm-like shape.
• Caterpillars, maggots,
and grubs are all just
the larval stages of
insects.
• Larvae molt their skin
several times and they
grow slightly larger.
Complete and Incomplete Metamorphosis
Pupa
• Larva make cocoons
around themselves.
• Pupa don't eat while
they're inside their
cocoons.
• Their bodies develop
into an adult shape with
wings, legs, internal
organs, etc.
• This change takes
anywhere from 4 days
to many months.
Complete and Incomplete Metamorphosis
Adult
• Inside the cocoon, the
pupa change into adults.
• After a period of time,
the adult breaks out of
the cocoon.
Insects with Complete
Metamorphosis…
• Lady bug
• Butterfly
• Mosquito
• Fleas
• Wasps
• Flies
Complete and Incomplete Metamorphosis
Frogs
• Frogs undergo a
different type of
complete
metamorphosis.
• From the egg emerges a
tadpole, which lives in
the water, breathes
with gills, and has a tail.
• As the tadpole grows,
lungs and legs form, and
the gills and tail are
absorbed into the body.
Complete and Incomplete Metamorphosis
Quiz
What are the two types of metamorphosis?
• Complete
• Incomplete
How many stages are there in incomplete metamorphosis?
• Answer: 3
How many stages are there in complete metamorphosis?
• Answer: 4
Name the stages in complete metamorphosis.
• Egg
• Larva
• Pupa
• Adult
Complete and Incomplete Metamorphosis
Quiz
Label all the stages.
Complete and Incomplete Metamorphosis
Complete and Incomplete Metamorphosis
Quiz
Complete or Incomplete Metamorphosis?
Answer
Complete Metamorphosis?
Complete and Incomplete Metamorphosis
Quiz
Complete or Incomplete Metamorphosis?
Answer
Incomplete Metamorphosis?
Complete and Incomplete Metamorphosis
END