登录

Chapter 28

Absorption of Nutrients

碳水化合物:膳食来源和要求
碳水化合物:膳食来源和要求
Carbohydrates are a fundamental part of the human diet, primarily acquired from milk and edible plant sources. The primary sugars  — ...
蛋白质:膳食来源和要求
蛋白质:膳食来源和要求
Proteins are essential macronutrients for the human body. They serve as vital structural materials, such as keratin and collagen, and functional proteins, ...
脂质:膳食来源和要求
脂质:膳食来源和要求
Dietary lipids, or fats, primarily comprising triglycerides, are essential to human nutrition. Saturated fats predominantly come from meat, dairy, and ...
维生素
维生素
Dietary vitamins are essential as they facilitate the utilization of various other nutrients. They predominantly act as coenzymes, assisting different ...
矿物
矿物
Minerals are elements that work with other nutrients to ensure healthy body function. The human body primarily requires seven minerals — calcium, ...
碳水化合物代谢概述
碳水化合物代谢概述
During digestion, polysaccharides are broken down into simple sugars. After their absorption in the GI tract, glucose is transported into other cells ...
蛋白质代谢概述
蛋白质代谢概述
During digestion, proteins are broken down into smaller peptides and amino acids, which are absorbed. The amino acids are not stored for later use. ...
脂质代谢概述
脂质代谢概述
Lipid metabolism includes lipolysis and lipogenesis. In lipolysis, dietary triglycerides are converted into fatty acids and glycerol, producing ATPs ...
胆固醇:意义和调节
胆固醇:意义和调节
The liver synthesizes most cholesterol from acetyl CoA and transports it to the blood through lipoproteins. These lipoproteins are of three types. VLDLs ...
碳水化合物吸收
碳水化合物吸收
Digestion of carbohydrates, such as dietary starch, begins in the mouth with chewing and the action of the salivary amylase. After being partially ...
蛋白质吸收
蛋白质吸收
Proteins in the gastrointestinal tract primarily come from food but can also originate from disintegrated cells or secreted enzymes. In the stomach, these ...
脂质吸收
脂质吸收
In the duodenum, dietary triglycerides in chyme are mixed with bile salts. This process breaks down large fat droplets into smaller ones. Once emulsified, ...
矿物质、维生素和水的吸收
矿物质、维生素和水的吸收
Essential elements, including iron, calcium, sodium, chloride, and bicarbonate, are primarily consumed as dietary minerals or ions. While most ...
身体的代谢状态:吸收状态
身体的代谢状态:吸收状态
The absorptive state is a well-fed period lasting approximately four hours after a meal when the body absorbs nutrients from the gastrointestinal tract. ...
身体的代谢状态:吸收后状态
身体的代谢状态:吸收后状态
The postabsorptive state typically begins about four hours after a meal and lasts until the next meal is consumed. During this period, the digestive ...
身体的代谢状态:禁食和饥饿
身体的代谢状态:禁食和饥饿
During the initial hours of fasting, the body depletes its glycogen stores for energy. As glycogen stores diminish, the body begins the breakdown of ...
能量平衡
能量平衡
Energy is released when the chemical bonds in organic compounds, such as carbohydrates, proteins, and fats, are broken down. Food energy is measured in ...
代谢率
代谢率
The body's metabolic rate refers to the overall rate at which metabolic reactions consume energy. It can be measured as the total metabolic rate or ...
体温
体温
The average body temperature is 98.6 degrees Fahrenheit. At rest, metabolically active organs like the liver, heart, brain, and endocrine organs are vital ...
传热机制
传热机制
Heat is transferred between the body and its surroundings in four ways. Conduction is the heat transfer between molecules of two materials in direct ...
温度调节
温度调节
The body regulates core temperature through negative feedback mechanisms. When the core temperature drops, thermoreceptors send signals to the ...
体温稳态失衡
体温稳态失衡
Hyperthermia is an umbrella term for elevated body temperature that occurs when heat production exceeds the body's ability to dissipate it. ...
食物摄入量的监管
食物摄入量的监管
The hypothalamus releases peptides influencing feeding behavior. Two hypothalamic neuronal groups participate in this process. Neuropeptide Y (NPY) and ...
肥胖
肥胖
Obesity is a clinical condition marked by excessive body fat, with a BMI of 30 or higher, while a BMI of 18.5 to 24.9 is considered healthy. Excess ...
先天性新陈代谢缺陷
先天性新陈代谢缺陷
Genetic anomalies that disrupt metabolic processes cause inborn errors of metabolism. Phenylketonuria is an autosomal recessive protein metabolism ...
JoVE Logo

政策

使用条款

隐私

科研

教育

关于 JoVE

版权所属 © 2025 MyJoVE 公司版权所有,本公司不涉及任何医疗业务和医疗服务。