"Chemical Substances and Health" Modern Life and Chemistry PPT Courseware 3

"Chemical Substances and Health" Modern Life and Chemistry PPT Courseware 3

learning target

1. Know the composition of the main chemical elements of the human body

2. Understand the important role of calcium, iron, zinc and other elements in human health.

3. Preliminarily understand the significant contribution of the development of chemical science in helping humans overcome diseases and nutritional health.

1. Chemical elements in the human body

[Thinking] Do you know what elements make up the human body? Which element is most abundant among the elements that make up the human body?

There are more than 50 elements that make up the human body. There are 11 elements that are abundant in the human body, with a content of more than 0.01%, and are called macroelements. They are oxygen, carbon, hydrogen, nitrogen, calcium, phosphorus, potassium, sulfur, sodium, chlorine, and magnesium, which account for 99.95% of the human body's mass.

The top four elements oxygen, carbon, hydrogen, and nitrogen (about 96% in total) in the human body exist in the form of water, protein, sugar, fat, and vitamins.

In addition to the 11 elements in the human body, other elements (about 4%) such as iron, zinc, selenium, iodine, etc., have their contents below 0.01% and are called trace elements. These elements exist mainly in the form of inorganic salts.

1. Chemical element in human body---Calcium

Function: Calcium provides a strong structural scaffolding for bones and teeth.

Dangers of calcium deficiency: Calcium deficiency in young children and adolescents can cause rickets and stunted development. Calcium deficiency in the elderly can lead to osteoporosis and easy fractures.

Content and distribution: The adult body contains approximately 1.2kg of calcium, 99% of which is found in bones and teeth. It mainly exists in the form of calcium hydroxyphosphate Ca10(PO4)6(OH)2 crystals.

How to supplement calcium:

①Try to take supplements as much as possible: Eat more milk, cheese, eggs, soy products, kelp, seaweed, dried shrimps, sesame seeds, hawthorn, marine fish, vegetables, etc., which contain more calcium. When eating these foods, you should avoid eating too much foods containing phytic acid, oxalic acid, and tannic acid to avoid the formation of insoluble calcium compounds, which will affect calcium absorption.

②The more calcium the better, the better. The important thing is to look at the absorption. Taking more than 200 milligrams of calcium each time will reduce the absorption rate.

③While supplementing calcium, pay attention to properly supplementing vitamin D. Vitamin D helps with calcium absorption. You should pay attention to increase outdoor activities and bask in the sun. Because ultraviolet rays can promote the conversion of cholesterol into vitamin D in the body.

2. Chemical element in human body---Iron

Iron is a component of hemoglobin and helps transport oxygen. Iron deficiency can cause iron deficiency anemia, making people weak, with pale skin, fatigue, dizziness, and sensitivity to cold.

Excessive iron intake (will produce chronic or acute iron poisoning. Chronic moderate symptoms are: the liver contains a large amount of iron, which will lead to cirrhosis, pancreatic fibrosis, etc. Acute iron poisoning causes severe and extensive necrosis of the gastrointestinal epithelium, eventually leading to death.

3. Chemical element in human body---zinc

Zinc affects human development, and the most common cause of zinc deficiency is an unbalanced diet. Zinc deficiency is characterized by loss of appetite, retardation of growth and development, rough and cracked skin, loss of taste sensitivity, lightening of hair pigment, white spots on nails, slow wound healing, etc. Zinc deficiency in pregnant women may even cause fetal malformations.

4. Chemical element in human body---Selenium

Selenium has anti-cancer and anti-cancer effects. Selenium deficiency is an important cause of Keshan disease. Selenium deficiency can induce liver necrosis and induce cardiovascular disease.

In people with mild or moderate selenium deficiency, the signs and symptoms are not obvious. Excessive intake of selenium will cause selenium poisoning, the symptoms of which are: gastrointestinal disorders, ascites, anemia, hair loss, nail and skin deformation, and liver damage. Normal people are at risk of poisoning if they consume 50 times more selenium than their physiological requirements.

Knowledge point 1, chemical elements and health

【Example 1】Scientific diet is the guarantee of health. Which of the following statements is correct ( )

⑴Vitamins and inorganic salts are essential nutrients for the human body

⑵Tofu is a food rich in protein

⑶ Zinc, selenium and other elements are essential trace elements for the human body. Nutritional supplements containing these elements should be taken in large quantities.

⑷Bone soup contains calcium and teenagers should consume it regularly to prevent rickets.

⑸To prevent goiter, add a large amount of iodine to table salt

A.⑴⑵⑷ B.⑵⑷⑸ C.⑴⑶⑷ D.⑴⑵⑷⑸

Knowledge point 2. Balanced diet

[Typical Example 2] The following is a classmate’s lunch recipe: braised pork, rice, fried peanuts, stewed chicken soup. The main nutrient missing in this classmate’s food is ( )

A.Protein

B.Sugar

C.vitamins

D.Grease

Keywords: Modern Life and Chemistry Teaching Courseware, Chemical Substances and Health Teaching Courseware, Guangdong Education Edition 9th Grade Chemistry PPT Courseware Download, 9th Grade Chemistry Slide Courseware Download, Modern Life and Chemistry PPT Courseware Download, Chemical Substances and Health PPT Courseware download, .PPT format;

For more information about the PPT courseware "Modern Life and Chemistry, Chemical Substances and Health", please click the "Modern Life and Chemistry ppt Chemical Substances and Health ppt" tag.

"Chemical Substances and Health" Modern Life and Chemistry PPT Courseware 2:

"Chemical Substances and Health" Modern Life and Chemistry PPT Courseware 2 Learning Objectives 1. Understand the important role of calcium, iron, zinc and other elements in human health; 2. Understand that nutrients refer to proteins, sugars, oils, vitamins, inorganic salts and Water and other six types of substances, master eggs...

"Chemical Substances and Health" Modern Life and Chemistry PPT Courseware:

"Chemical Substances and Health" Modern Life and Chemistry PPT Courseware New Knowledge Preview 1. Elements in the Human Body 1. Existence form: There are more than 50 elements in the human body, among which ____, ____, ____, ____ and other elements are mainly composed of water, sugar, fat, protein and vitamins..