《寄生虫学》课程PPT教学课件：完全和不完全变态 Complete and Incomplete Metamorphosis

Complete and Incomplete metamorphosis

Complete and Incomplete Metamorphosis

What is metamorphosis? Metamorphosis refers to the way that certain organisms develop, grow, and change form Metamorphosis actually means change

• Metamorphosis refers to the way that certain organisms develop, grow, and change form. • Metamorphosis actually means "change". What is metamorphosis?

Felt he was an outsider Jewish in Catholic Prague conely Perceived human beings as being trapped by authority in a hopeless world Became frustrated at having to support his family Had to work in a meaningless bureaucratic job where he was Just another pencil pusher Took time away from his writing franz Kafka

Franz Kafka • Felt he was an outsider – Jewish in Catholic Prague – Sickly – Lonely • Perceived human beings as being trapped by authority in a hopeless world • Became frustrated at having to support his family • Had to work in a meaningless bureaucratic job where he was just another pencil pusher – Took time away from his writing

Two Types oi Metamorphosis COMPLETE METAMORPHOSIS has four stages INCOMPLETE METAMORPHOSIS- has three stages(ps incomplete doesn't mean not finished. It just means that the adult in complete metamorphosis is completely different from the larva. a nymph and its adult form are not completely different. They ' re only a little different

• COMPLETE METAMORPHOSIS - has FOUR stages. • INCOMPLETE METAMORPHOSIS - has THREE stages (p.s. incomplete doesn’t mean not finished. It just means that the adult in complete metamorphosis is completely different from the larva. A nymph and its adult form are not completely different. They’re only a little different.) Two Types of Metamorphosis

4 STAGES OF COMPLETE METAMORPHOSIS °Egg Larva Larva Eggs Adult upa Adult

• Egg • Larva • Pupa • Adult 4 STAGES OF COMPLETE METAMORPHOSIS

Adult O EGG Pupa Larva The female lays eggs

• EGG • The female lays eggs

LARVA pa Larva Larva hatch from the eggs they uo not look like adult insects. They usually have a worm like shape Caterpillars(毛虫), maggots(蛆虫),and grubs(蛴螬) are all just the larval stages of insects. Larvae molt their skin several times and they grow slightly larger

• LARVA • Larva hatch from the eggs. They do not look like adult insects. They usually have a worm￾like shape. • Caterpillars(毛虫）, maggots (蛆虫）, and grubs（蛴螬）are all just the larval stages of insects. Larvae molt their skin several times and they grow slightly larger

ADULT Adult Inside the cocoon, the larvae change into adults. After a period of time, the adult breaks out of the cocoon

• ADULT • Inside the cocoon, the larvae change into adults. After a period of time, the adult breaks out of the cocoon

INCOMPLETE METAMORPHOSIS Let's take a closer look at each stage Simple Metamorphosis L Lead hug nymph Nymphs egg Eggs Adult adult

Let’s take a closer look at each stage! INCOMPLETE METAMORPHOSIS

3 STAGES OF INCOMPLETE METAMORPHOSIS 88 Nymph adult ·Adu|t

• Egg • Nymph • Adult 3 STAGES OF INCOMPLETE METAMORPHOSIS