"Human Food" PPT

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"Human Food" PPT

Part 1: Think about it

Do you know which organisms human food comes from?

Why do we eat these foods?

What nutrients can food provide us?

do you know?

1. Have you ever eaten tofu? What are its main raw materials? What kind of nutrients is it rich in?

2. Some people don’t like to eat fruits and vegetables, but they are still healthy, but their teeth will bleed every time they brush their teeth. Do you know why?

3. Teenagers should drink at least one bag of milk every day. Do you know what nutrients are rich in milk?

4. Do you know how to detect protein?

5. Do you know how to test vitamin C?

Human Food PPT, Part 2: Classroom Experiment

Experiment 1: Detection of Protein

1. In the experiment, what is the purpose of setting up test tube B?

for controlled experiments

2. Why do the solutions in test tubes A and B change color differently?

The protein in test tube A can interact with the biuret reagent to turn the egg white purple.

The water in test tube B does not react with the biuret reagent.

Experiment 2: Detection of Vitamin C

1. In the experiment, what is the purpose of setting up test tube B?

Controlled experiment

2. Why are the colors of the solutions in test tubes A and B different?

The reagent dropped into test tube A reacts with vitamin C and fades, which is called fading reaction. The reagent dropped into test tube B dyed the water blue.

3. What kind of water-soluble substances can be detected with indoxyl?

Test vitamin C, because vitamin C can cause fading reactions with indoxyl.

Human Food PPT, Part 3: Course Extension

The Discovery of Vitamin C - Reading Materials

In 1519, Portuguese navigator Magellan led an ocean-going fleet from the east coast of South America to the Pacific Ocean. Three months later, some crew members had broken gums, some had nosebleeds, and some were weak. When the ship arrived at its destination, only 35 of the original more than 200 people survived, and people could not find out. reason.

In 1734, on a ship bound for Greenland, a crew member suffered from severe scurvy. The disease was untreatable at the time, and the other crew members had to abandon him on a desert island. When he regained consciousness, he ate wild grass to satisfy his hunger. After a few days, his scurvy was cured without any treatment.

Scurvy like this killed hundreds of thousands of British sailors. In 1747, the British naval doctor Lynde summarized the experience of his predecessors and suggested that the crew of the navy and expedition fleet should eat more lemons during long voyages. His advice was adopted, and scurvy has never occurred since then. But at that time, it was not known what substances in lemons had resistance to scurvy.

Keywords: Beijing Normal University Edition Biology PPT courseware for seventh grade volume 2 free download, human food PPT download, .PPT format;

For more information about the "Nutrition of the Human Body and Food for Humans" PPT courseware, please click on the "Nutrition of the Human Body PPT and Human Food PPT" tags.

"Human Food" PPT download:

"Human Food" PPT Download Part One Content: Objectives and Key Points [Learning Objectives] 1. Try to analyze the nutrients in food and explain the important effects of various nutrients on the human body. 2. Improve experimental operation capabilities by exploring the nutritional components of food..

"Human Food" PPT courseware:

"Human Food" PPT Courseware Part One: Nutrition in Food What nutrients are in human food? Why do we need these foods? Testing of nutrients. Testing of water. After baking, water droplets appeared on the wall of the test tube. Detection of inorganic salts...

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Update Time: 2024-10-21

This template belongs to biology courseware Beijing Normal University Edition Seventh Grade Biology Volume 2 industry PPT template

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