"Observe the living world around you with a microscope (3)" Tiny World PPT

Description

"Observe the living world around you with a microscope (3)" Tiny World PPT

Part One: Observing Microorganisms in Water

Since Leeuwenhoek discovered microorganisms with a homemade microscope, scientists have discovered through observation that there are many microorganisms living in nature.

Let's look at microorganisms in water under a microscope.

Microorganisms are a general term for all tiny organisms that are invisible or unclear to the naked eye.

Microorganisms are a large group of organisms including bacteria, viruses, fungi and some small protozoa.

Use a dropper to pick up a drop of pond or fish tank water, place it on a glass slide, cover it with a cover slip, and observe it under a microscope.

If the microorganisms move quickly and are difficult to observe, we can first put a small amount of absorbent cotton fiber on the slide, then drop a drop of pond water on it, and cover it with a cover slip. You can also use absorbent paper on the edge of the coverslip to absorb excess water to control the movement of microorganisms.

Have you observed microorganisms in the water? What is it like? Draw detailed drawings of the microorganisms you observed.

Do you think they have biological characteristics?

① Living things need nutrition;

② Living things can breathe;

③Biological energy removes waste from the body;

④ Biological organisms can respond to external stimuli;

⑤ Living things can grow and reproduce;

⑥All living things are composed of cells (except viruses);

⑦All living things have heredity and variation.

Use a microscope to observe the living world around you PPT, Part 2: Understanding common water microorganisms

Paramecium

Paramecium lives in stagnant fresh water and looks like a straw sandal. There are many cilia on the surface of the body that can swing. Paramecium has only one cell, but this one cell can complete all life activities such as digestion, respiration, excretion, and reproduction. Paramecium uses cilia to sense the surrounding environment and moves freely by rowing the cilia like an oar. Paramecium's food is bacteria and single-celled algae. It absorbs food into the body through the cell opening, and indigestible food residues are excreted through the anus.

Paramecium can respond sensitively to external stimuli. Under extremely harsh conditions, a tough shell-like membrane will form on its cell surface, making it unable to eat.

Under normal circumstances, the way Paramecium reproduces is to first elongate the body, then split into two parts from the middle, and finally each part forms a young Paramecium.

amoeba

Amoebas live in fresh water or soil, are about 1mm in length, and have only one cell. As the name suggests, amoebas are shape-shifting. Anywhere on the cell can protrude into pseudopods, and the direction in which the pseudopods protrude is the direction of its movement. Feeding, elimination of food debris, and respiration of amoeba can occur from any part of the body surface. They use pseudopods to wrap up their prey and create a food bubble to digest and absorb the prey. Its reproduction mode changes from one to two, and two to four... When the environment is harsh, it can also form a cell shell and go dormant.

trumpet bug

Trumpet bugs are shaped like trumpets, come in various colors, and are covered with uniform cilia. Most species live in fresh water such as ponds, ditches, and rice fields, while a few live in the ocean. Trumpet worms often use the attachment device at the rear end to attach to other objects. When stimulated, the whole body contracts, and the body cilia can also be used to swing to swim in the water. Often feed on small organisms and organic matter in the water. Trumpet worms have two ways of reproduction, one is to split the body transversely and split into two; the other is to reproduce by conjugation. Trumpet worms are very capable of regenerating and can survive in harsh conditions.

Use a microscope to observe the living world around you PPT, Part 3: Class Summary

After studying this lesson, what new insights did you gain?

Using a microscope, you can see many tiny organisms that are invisible to the naked eye.

There are many microorganisms of various forms living in the water.

Microorganisms are living things and share common characteristics with other living things.

Keywords: Free download of Chinese PPT courseware for the second volume of the sixth grade in the textbook version, use a microscope to observe the living world around you PPT download, download of the tiny world PPT, .PPT format;

For more information about the PPT courseware "Use a Microscope to Observe the Living World Around You in a Tiny World", please click on the Tiny World ppt Use a Microscope to Observe the Living World Around You ppt tag.

"Tiny World and Us" Tiny World PPT download:

"Tiny World and Us" Tiny World PPT Download Part One: Review and Summary How have human observation tools developed from ancient times to the present? How do people expand their observation horizons? ... ... ... Tiny World and Us PPT, Part 2...

"Tiny World and Us" Tiny World PPT:

"Tiny World and Us" Tiny World PPT Part One Content: Review and Summary Review the learning content of this unit, think about how human observation tools have developed from ancient times to the present, and how people's observation horizons have expanded. Let's talk about two relationship between them. ..

"Use a microscope to observe the living world around you (3)" Micro World PPT teaching courseware:

"Observe the living world around you with a microscope (3)" Micro World PPT teaching courseware Part One: Questions before class 1. Move the film to the left, where will the objects under the microscope move? Move to the right 2. What does the word above look like when placed under a microscope? 3.How to make foreign...

File Info

Update Time: 2024-09-11

This template belongs to science courseware Science Edition for Sixth Grade Science Volume 2 industry PPT template

Preview