"Amphibians and Reptiles" Main Groups of Animals PPT Courseware 3

Description

"Amphibians and Reptiles" Main Groups of Animals PPT Courseware 3

What does "amphibious" mean in amphibians?

Larvae live in water and breathe through gills

Adults live on land and breathe with lungs

1. Observation and exploration

Take a look:

1. Observe the body shape and color of the frog. Are the dorsal and ventral sides of the frog the same color?

2. Observe the characteristics of the frog’s forelimbs and hindlimbs, and what structures are there between the toes?

Touch it:

Touch the frog's skin with your hands, and then gently hold its body. What does it feel like?

1. Skin: The skin is smooth, exposed, and can secrete mucus.

2. Body temperature: body temperature is not constant

2. Reading Q&A

——Amphibians are a group that transitions from aquatic to terrestrial. It not only has new characteristics adapted to terrestrial life, but also retains the aquatic life of its ancestors.

Please read P26 to find out the characteristics of frogs adapting to the two environments.

Structure conforms to function, and organisms adapt to the environment

Adaptation to land:

1. Sensory organs 2. Respiratory organs 3. Motor organs

Adaptation to water:

1. Naked, secretes mucus, reduces resistance when swimming.

2. There are webs between the toes, which is convenient for paddling.

These characteristics of the frog make it adaptable to both water and land living environments.

Reasons why amphibians cannot completely escape from water:

1. Breathing problems

Lung breathing is not enough to bear the gas required for life on land.

Metabolism requires assistance from the skin or gills.

2. Water retention problem

It simply fails to solve the problem of preventing evaporation of water in the body while living on land.

Skin resistance is opposed to skin respiration.

3. Reproduction problem

The reproduction and development process must also be completed in water.

Why do frogs have the habit of hibernating?

1. The lungs have a simple structure and poor ability to absorb oxygen from the air. They must rely on the skin to assist breathing and have weak heat production capabilities.

2. The heart has two atriums and one ventricle. There is a part of mixed blood in the ventricle, which has a low ability to transport oxygen.

3. There are no specialized insulation structures such as feathers or hair on the body surface.

Frogs and fish are cold-blooded animals

test you

1. The reason why frogs are called “amphibians” is ( )

A. Larvae live in water, adults can only live on land

B. Reproduce in water and develop on land.

C. The larvae live in water and breathe with their gills; the adults can live on moist land or in water and mainly breathe with their lungs.

D. Frogs can live in water as well as on land.

2. The meaning of bare and moist skin ( )

A. Protect body water from loss

B. Conducive to the exchange of gases between the body surface and the outside world

C. Reduce swimming resistance

D. Adapt to life in the water and be flexible in movement

Keywords: teaching courseware of the main groups of animals, teaching courseware of amphibians and reptiles, download of the biology PPT courseware of the first volume of the eighth grade of the People's Education Edition, download of the biology slide courseware of the eighth grade, download of the PPT courseware of the main groups of animals, amphibians and reptiles PPT courseware download, .PPT format;

For more information about the "Main Groups of Animals Amphibians and Reptiles" PPT courseware, please click the "Main Groups of Animals ppt Amphibians and Reptiles ppt" tag.

"Amphibians and Reptiles" Main Groups of Animals PPT Courseware 5:

"Amphibians and Reptiles" Main Groups of Animals PPT Courseware 5 Think about it and discuss it Frogs and turtles can live in both water and land. However, frogs are amphibians and turtles are reptiles. Why is this? What is the representative animal of amphibians? ..

"Amphibians and Reptiles" Main Groups of Animals PPT Courseware 4:

"Amphibians and Reptiles" Main Groups of Animals PPT Courseware 4 1. Amphibians 1. Representative animal frog: Fill in the names of each part of the frog: (1) Development of the frog. ①Tadpoles: have tails, breathe with ___, and can only live in _____. ②Frog:_______..

"Amphibians and Reptiles" Main Groups of Animals PPT Courseware 2:

"Amphibians and Reptiles" Main Groups of Animals PPT Courseware 2 Learning Objectives 1. Main characteristics of amphibians and reptiles 2. Their relationship with human life 1. Think about amphibians and discuss frogs and turtles. You can also swim in the water...

File Info

Update Time: 2024-11-22

This template belongs to biology courseware People's Education Edition Biology for Grade 8, Volume 1 industry PPT template

Preview