Human Digestive System: Functions and Organs
Functions of the Digestive System
- Digestion of Food: Breakdown of food into smaller particles.
- Mechanical Digestion: Changes the physical form of food.
- Chewing in the mouth
- Churning in the stomach.
- Chemical Digestion: Enzymes change the chemical composition of food.
- Lipids to fatty acids
- Proteins to amino acids
- Carbohydrates into simple sugars
- Absorption of Nutrients: Transport of nutrients to the blood.
- Assimilation of Nutrients: Transport of nutrients into the cells.
- Egestion of Faeces: Semi-solid waste
Photosynthesis: Light Energy to Sugar
Photosynthesis
Plants are autotrophs, meaning they are self-nourishing.
Electromagnetic Spectrum
- Shortest wavelength = Gamma rays
- Then X-rays
- Then UV radiation
- Then visible light (ROYGBIV)
- Then infrared radiation
- Then microwaves
- Longest wavelength = Radio waves
Photons are packets of light energy. They have differing amounts of energy depending on their wavelengths.
Pigments
The color you see is the wavelengths not absorbed.
The light-catching part of a molecule contains electrons that move to higher energy
Read MoreUnderstanding Food Webs: Terrestrial and Aquatic Ecosystems
Food Webs
Of course, the real world is much more complicated than a simple food chain. While many organisms have very specialized diets, such as anteaters, in most cases, this is not true. Snakes do not limit their diets to frogs, and frogs and toads eat more than just black ants. Every living thing feeds on different prey types and, in turn, is prey to different predators. In addition, some organisms (like mice and birds) include both plants and animals in their diets. This determines that ecosystems
Endocrine System: Hormones and Glands in the Human Body
Endocrine Regulation
The proper functioning of our body is due to the joint coordination of two mechanisms: nervous control and hormonal control. The first is through the action of the nervous system in three sections: central, peripheral, and autonomic. The central control takes place through the action of a group of organs called endocrine glands and internal secretion, which produce chemicals called hormones.
Meaning and Origin of Gland
A gland is an organ whose cells are specialized in the production
Read MoreCirculatory and Excretory Systems: Functions and Anatomy
What is the Circulatory System?
The circulatory system is responsible for carrying the products of digestion and oxygen obtained through the respiratory system to all the cells of the body. It also collects waste products and takes them to the excretory system where they will be eliminated.
What Organs Form the Circulatory System?
It is formed by a central body called the heart and blood vessels (arteries, veins, and capillaries).
How is the Heart Shaped?
The heart is a hollow organ composed of muscle
Read MorePhotosynthesis: Energy Input and Factors Affecting It
Photosynthesis: A Unique Mechanism of Energy Input
Photosynthesis is a unique mechanism for energy input into the biosphere. Light is captured and converted into chemical energy in the form of organic matter, stored as carbohydrates, producing free O2. This process distinguishes the plant kingdom. It is influenced by the following factors: light, temperature, air humidity, water availability, carbon dioxide (CO2), and nutrients. Free oxygen in the atmosphere reaches 21%.