Transmission of Common Diseases Transmission of cholera Cholera is caused by the bacterium Vibrio cholerae The disease is water-borne (the bacterium lives in water) and food-borne This means the di...
Infectious Diseases A disease is an illness or disorder of the body or mind that leads to poor health Each disease is associated with a set of signs and symptoms Infectious diseases are caused by p...
Gas Exchange Processes The exchange of oxygen and dioxide occurs between the alveoli and the capillaries in the lungs Oxygen and carbon dioxide are exchanged in a process of simple diffusion; (pass...
The Gas Exchange System: Structure & Functions Ciliated epithelial cells, goblet cells and mucous glands play vital roles in maintaining the health of the gas exchange system Cartilage, smooth ...
Recognising Structures in the Gas Exchange System Trachea Trachea cross-section A tracheal cross-section shows the large lumen which air has to travel through The innermost cells of the trachea are...
Recognising Tissues in the Gas Exchange System Cartilage Cartilage micrograph Cartilage – electron micrograph The cartilage in the trachea has a ‘glassy’ appearance due to its translucent protoplas...
Distribution of Tissues in the Gas Exchange System Cartilage is a strong and flexible tissue found in various places around the body One place is in rings along the trachea, called Tracheal rings T...
The Human Gas Exchange System Gas exchange takes place in the human thorax. This is a collection of organs and tissues in the chest cavity The main structures of the human gas exchange system Thora...
Heart Action: Initiation & Control Control of the basic heartbeat is myogenic, which means the heart will beat without any external stimulus This intrinsic rhythm means the heart beats at aroun...
The Cardiac Cycle The contraction of the heart is called systole, while the relaxation of the heart is called diastole Atrial systole is the period when the atria are contracting and ventricular sy...
The Walls of the Heart The muscular walls of the atria are thinner than those of the ventricles When the atria contract, the thin muscular walls do not generate much pressure, but enough to force b...
英国留学选专业是个技术活，好的专业能够为今后的职业生涯开辟一条广阔的道路。哪些专业在就业市场上最受欢迎？今天就来讲讲罗素大学集团最受欢迎学科之一：地理学专业怎么样？ 专业定义 地理学专业是一门从各种...
