Respiration

Respiration Respiration is defined as the movement of oxygen from the outside environment to the cells within tissues, and the transport of carbon dioxide in the opposite direction. The physiological definition of respiration is differs from the biochemical definition, which refers to cellular respiration, a metabolic process by which an organism obtains energy (in the … Read more Respiration

Types of respiration

Types of respiration External Respiration One method for obtaining oxygen from the environment is through external respiration or breathing. In animal organisms, the process of external respiration is performed in a number of different ways. Animals that lack specialized organs for respiration rely on diffusion across external tissue surfaces to obtain oxygen. Others either have … Read more Types of respiration

Structure and working of heart and blood vessels

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 Structure and working of heart and blood vessels

Human reproductive system and reproduction process

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 Human reproductive system and reproduction process

Respiratory system of human being and mechanism of respiration

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 of human being and mechanism of respiration

Human digestive system and digestive process

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 Human digestive system and digestive process