Respiratory System

Respiratory System Introduction Red blood cells are like trucks that transport cargo on a highway system. Their cargo is oxygen, and the highways are blood vessels. Where do red blood cells pick up their cargo of oxygen? The answer is the lungs. The lungs are organs of the respiratory system. The respiratory system is the … Read more Respiratory System

Circulatory System

Circulatory System The circulatory system can be compared to a system of interconnected, one-way roads that range from superhighways to back alleys. Like a network of roads, the job of the circulatory system is to allow the transport of materials from one place to another. As described in Figure below, the materials carried by the … Read more Circulatory System

Reproductive systems

Reproductive systems The reproductive system in both males and females consists of structures that produce reproductive cells, or gametes, and secrete sex hormones. A gamete is a haploid cell that combines with another haploid gamete during fertilization. Sex hormones are chemical messengers that control sexual development and reproduction. The male reproductive system consists of structures … Read more Reproductive systems

Digestive System

Digestive System Introduction The respiratory and circulatory systems work together to provide cells with the oxygen they need for cellular respiration. Cells also need glucose for cellular respiration. Glucose is a simple sugar that comes from the food we eat. To get glucose from food, digestion must occur. This process is carried out by the … Read more Digestive System

Food preservatives

Food preservatives Food preservatives constitute a group of compounds of widely different molecular structures; they are organic and inorganic substances with different functional groups and tendencies to form ions. There are no procedures that are generally applicable to the analysis of preservatives as a class of food additive; the procedures are specific to the preservative … Read more Food preservatives

Introduction to alkaloids (nicotine and cocaine)

Introduction to alkaloids (nicotine and cocaine) Alkaloids, any of a class of naturally occurring organic nitrogen-containing bases. Alkaloids have diverse and important physiological effects on humans and other animals. Well-known alkaloids include morphine, strychnine, quinine, ephedrine, and nicotine. Alkaloids are found primarily in plants and are especially common in certain families of flowering plants. More … Read more Introduction to alkaloids (nicotine and cocaine)

Preliminary idea of medicine and its classification

Preliminary idea of medicine and its classification Medicine is the field of health and healing. It includes nurses, doctors, and various specialists. It covers diagnosis, treatment, and prevention of disease, medical research, and many other aspects of health. Medicine aims to promote and maintain health and wellbeing.  Conventional modern medicine is sometimes called allopathic medicine. … Read more Preliminary idea of medicine and its classification

Steroids and Cholesterol

Steroids Steroids are naturally made by our bodies in small amounts. They help to control many functions. But steroids can also be made artificially and used as drugs to treat different diseases, including cancer.  Steroids used to treat cancer are usually a type called corticosteroids. These are man made versions of the hormones produced by … Read more Steroids and Cholesterol

Carbohydrates (glucose, sucrose and cellulose)

Carbohydrates (glucose, sucrose and cellulose) Carbohydrates (also called saccharides) are molecular compounds made from just three elements: carbon, hydrogen and oxygen. Monosaccharides (e.g. glucose) and disaccharides (e.g. sucrose) are relatively small molecules. They are often called sugars. Other carbohydrate molecules are very large (polysaccharides such as starch and cellulose). Carbohydrates are: a source of energy for the … Read more Carbohydrates (glucose, sucrose and cellulose)

Blood groups

Blood groups Blood group, classification of blood based on inherited differences (polymorphisms) in antigens on the surfaces of the red blood cells (erythrocytes). Inherited differences of white blood cells (leukocytes), platelets (thrombocytes), and plasma proteins also constitute blood groups. English physician William Harvey announced his observations on the circulation of the blood in 1616 and … Read more Blood groups