Karl Landsteiner in 1900 discovered that blood in all persons is not alike and hence clumping or agglutination occurs on the mixing of blood of certain persons. Blood group is determined by the antigens present on the surface of RBC’s. An antigen is a molecule (in this case a carbohydrate) that acts as a signal, […]
Since the heart relies on aerobic respiration to supply its energy needs, cardiac muscle cells are richly supplied with mitochondria. Our hearts beat about once every second of every day of our lives or over 2.5 million times in an average life span. The only time the heart gets a rest in between beats. Position: […]
Regulation of Cardiac Activity: Normal activities of the heart are regulated in an essential or natural way, meaning it is autoregulated by specialized muscles or the nodal tissue, therefore the heart is called myogenic. A special neural center in the medulla oblongata can moderate the cardiac function through the autonomic nervous system (ANS). Neural signals can […]
In this article, we shall study the origin and measurement of blood pressure. Origin of Blood Pressure: Due to the contraction of the heart and by the muscles that surround our blood vessels, blood moves through our circulation system since it is under pressure by it. The measure of this force is blood pressure. In […]
In this article, we shall study blood vessels and their types: arteries, veins, and capillaries. Study of blood vessels is called Angiology. Blood vessels form a network of blood circulating vessels starting from the heart (left ventricle) arteries arterioles capillaries venules veins back to the heart (right auricle). Arteries and Arterioles: Arteries carry blood from […]
In this article, we shall study types of blood circulation in human body. Pattern of Circulation Our Blood moves through the body in an uninterrupted fashion in the following sequence: 1] Left ventricle 2] systemic circulation (body) 3] right atrium 4] right ventricle 5] pulmonary circulation (lungs) 6] left atrium left ventricle. Double Circulation: Double […]
In this article, we shall study heart-related disorders and heart surgeries Hypertension: Symptoms: A healthy adult has a blood pressure reading of about 120/80 mm Hg (120 mm Hg – systolic and 80 mm Hg – diastolic). This often rises normally with age to about 130/90 at 60. Abnormally high blood pressure is known as […]
Tissue Fluid and Lymphatic System: 10% of its fluid escape into the surrounding tissues, as blood proceeds through the capillaries and is known as tissue fluid. Chemicals such as glucose and hormones are carried by this fluid to the cells of the body that are not next to the capillary. It then removes the waste […]
Science > Biology > Gene its Nature, Expression and Regulation > Nucleotides In this article, we shall study structural units of nucleic acid called nucleotides. In 1869, Friedrich Miescher separated cellular substance from the nuclei of pus cell and called it ‘Nuclein’. Due to acidic nature, the substance is further called as nucleic acid. There are […]
Science > Biology > Gene its Nature, Expression and Regulation > Genetic Material DNA as Genetic Material Griffith Experiment: Background: Meischer isolated nuclein from nuclei of WBCs in 1869. Walter Sutton, Thomas Hunt Morgan established that the hereditary material lies in the nucleus in chromosomes. Chromosomes are formed of proteins and nucleic acid, DNA. For […]