basic life processes

• haemoglobin has 4 subunits: 2 alpha, 2 beta, each with an iron -containing haeme group that binds to one oxygen molecule
• haemoglobin A has a diameter of 5nm
• a platelet is a eukaryotic cell fragment
• a tissue is a group of cells with similar structure and funtion, and the material surrounding them
• the endocrine glands are the kidney, pituatary gland, pineal gland, thyroid, adrenals, and pancreas
• blood pressure homeostasis: set point is 120/80, sensor is baroreceptors, control centre is nervous system, effectors are heart and blood vessels, and messages are nervous system signals and hormones
• temperature homestasis: set point is 37, sensors are in brain and hypothalamus, control centre is the nervous system, effectors can be blood vessels, muscle and sweat glands, messages are nervous system signals and hormones
• in blood glucose homestasis, sensor is B cells, control centre is pancreatic islets and the effector is insulin