"Animal Eggs" New Life PPT Courseware

Description

"Animal Eggs" New Life PPT Courseware

Review previous lessons

1. The _____ of male animals and the _____ of female animals combine to form _______, and a new life begins.

2. There are two types of animal reproduction activities.

Oviparous: lay eggs or eggs, such as fish, insects, birds

Viviparous: giving birth to small animals directly and feeding them with milk, such as cats, dogs, and humans.

butterfly eggs

Egg-laying time: spring and summer

Egg-laying method: Spread eggs one by one on plants

Egg size: very small, like a grain of rice

frog eggs

Egg-laying time: early spring

Spawning method: gather eggs in water

Egg size: Large, visible to the naked eye

fish eggs

Egg-laying time: mostly in spring and summer

Spawning method: gather eggs in water

Egg size: Small, about the size of a grain of rice

Observe the most common egg - egg

1.Put the egg in the palm of your hand and squeeze it

It is not easy to crush because the egg is oval and has a high endurance.

2. Use a magnifying glass to observe the surface of the eggshell

There are many small pores on the outside. The chicks need to breathe when they hatch.

3. Observe a raw egg

4. Observe a cooked egg

Egg shell and shell membrane: play a protective role

If the eggshell is soaked in vinegar or some acidic solution for a period of time, the eggshell will disappear and become a shellless egg, leaving only a thin film.

The yolk is the main nutritional part of the egg cell and is surrounded by the vitelline membrane. There is a disc-shaped white spot in the center of the yolk surface, called the blastoderm, which contains the nucleus.

I see:

(Fertilized) raw eggs are composed of shell, egg blue, egg yolk, and embryo. Unfertilized eggs have no embryo, so they cannot hatch chicks.

The protein of cooked eggs is what we often call (egg blue), and the small white dots on it are (embryos), which are formed by the division of fertilized eggs and are the parts that carry out embryonic development.

For the egg composition of other animals, we call it egg shell, egg white, yolk and embryo.

Like frogs and chickens, the method of reproducing offspring by ( ) is called ( ). Animals that reproduce in this way are called ( )

A fertilized frog egg can hatch ( ) in about ( ) days, and it takes about ( ) weeks for a fertilized egg to hatch into a chick.

Which of the following animals lay eggs? ( )

① Butterfly ② Elephant ③ Chicken ④ Snake ⑤ Frog ⑥ Crucian carp ⑦ Turtle ⑧ Snail ⑨ Pigeon ⑩ Tiger

Keywords: New life teaching courseware, Animal eggs teaching courseware, Educational Science Edition fourth grade science PPT courseware download, Volume 2, Fourth grade science slide courseware download, New life PPT courseware download, Animal eggs PPT courseware download, .PPT Format;

For more information about the "New Life Animal Eggs" PPT courseware, please click the New Life ppt Animal Eggs ppt tag.

"Animal Egg" New Life PPT Download:

"Animal Eggs" New Life PPT Download Part One: New Knowledge Explanation 1. Animal Eggs I discovered that the sizes of eggs of different animals...

"Animal Egg" New Life PPT:

"Animal Eggs" New Life PPT Part One: Animal Eggs Collect eggs of various animals and observe their similarities and differences. Butterfly eggs Frog eggs Toad eggs Fish eggs Eggs of various birds Use a magnifying glass to observe the outside of the egg, we will find...

"Animal Eggs" New Life PPT Courseware 3:

"Animal Eggs" New Life PPT Courseware 3 The functions of various parts inside the egg A. Proteins provide nutrients and moisture. B. Egg yolk provides nutrients. C. The embryo develops into a chick. D． The air chamber provides oxygen. E. The eggshell protects the embryo inside the egg. ....

File Info

Update Time: 2024-09-28

This template belongs to science courseware Fourth Grade Science Volume 2, Textbook Edition industry PPT template

Preview