The endocrine system

• The endocrine system consists of a number of glands that secrete hormones directly into the bloodstream.
• The blood carries the hormones all around the body but each hormone only acts on specific target organs where it produces an effect.
• The nervous system uses electrical impulses which travel down neurons, however the endocrine system uses hormones which are chemicals and these are carried in the bloodstream.
• Signaling in the nervous system is extremely fast, however the endocrine system tends to produce a much slower effect and the effect is more long-lasting.
• The key glands in the endocrine system include the pancreas, ovaries, testes, thyroid gland, adrenal glands, and pituitary gland.
• The pancreas releases hormones involved in controlling the concentration of glucose in the blood.
• The ovaries and testes release hormones involved in puberty and reproduction.
• The thyroid gland produces hormones involved in growth and regulating the body's basal metabolic rate.
• The adrenal glands release a hormone called adrenaline which is produced in times of fear or stress.
• The pituitary gland, located in the brain, is extremely important and is referred to as the master gland.
• The pituitary gland releases a number of different hormones into the blood depending on the conditions.
• Pituitary hormones act on other glands and cause other hormones to be released, triggering a range of different effects in the body.
• The endocrine system allows different parts of our body to communicate with each other, similar to a nervous system.
• The endocrine system consists of a series of glands that are found throughout the body, each secreting hormones which are small chemical molecules that are passed into the blood and then spread throughout the body in the bloodstream.
• Hormones from the endocrine system come into contact with a wide range of tissues, some of which have receptors that are specific to the hormones.
• Hormone molecules can act as signals to trigger certain changes inside the cells.
• The pituitary gland, also known as the master gland, produces multiple different hormones, some of which directly tell the body what to do and some which tell other glands to release their own hormones.
• The thyroid gland produces the hormone thyroxine which relates the rate of our metabolism and plays an important role in growth and development.
• The pituitary gland releases hormones that influence other glands, for example, thyroid stimulating hormone or TSH, which stimulates the thyroid to produce more thyroxine if levels are low.
• The kidneys contain Drina glands that produce adrenaline, which is normally released during the fight-or-flight response when we're startled or scared, increasing heart rates and generally getting blood pumping faster.
• The pancreas produces the hormone insulin which helps us to regulate our blood glucose concentrations.
• The testes in males and the ovaries in females produce hormones that influence puberty and the menstrual cycle.
• The endocrine system differs from the nervous system in that it relies on hormones which are small molecules secreted by glands and transported in the blood, while the nervous system relies mainly on electrical impulses which are transferred along nerve cells.
• Hormones from the endocrine system spread more slowly and their effects last longer than nerve impulses, which are sent very fast and their effects don't last very long.
• Hormones from the endocrine system act more generally as they spread through the entire body, interacting with loads of different cells, while nerve impulses are sent to one specific area such as the particular muscle that we need to move our arm.
• The nervous system is often described as being precise as nerve impulses are sent to one specific area such as the particular muscle that we need to move our arm, while hormones from the endocrine system spread more slowly and their effects last longer, interacting with loads of different cells.