Electron Shells Shells The arrangement of electrons in an atom is called the?electron?configuration Electrons are arranged around the nucleus in?principal energy levels?or?principal quantum ...
Time of Flight Mass Spectrometry Mass Spectrometry is a powerful analytical technique It is the most useful instrument for accurate determination of the relative atomic mass of an element, b...
Subatomic Structure of Atoms & Ions The mass of an atom is?concentrated?in the nucleus, because the nucleus contains the heaviest subatomic particles (the neutrons and protons) The mass ...
Edexcel IGCSE Biology 復(fù)習(xí)筆記 2.10.1 Homeostasis Response to Change: Homeostasis Homeostasis is the?control?or?regulation?of the?internal?conditions?of a cell or organism Some examples of t...
Edexcel IGCSE Biology 復(fù)習(xí)筆記 2.9.5 Regulating Water Content in the Blood Regulating Water Content in the Blood Osmoregulation?is the process of maintaining water and salt concentrations (o...
Edexcel IGCSE Biology 復(fù)習(xí)筆記 2.9.4 Kidney Structure & Function The Kidney The kidneys are located in the back of the abdomen and have two important functions in the body: They regulate...
Edexcel IGCSE Biology 復(fù)習(xí)筆記 2.9.3 The Urinary System The Urinary System: Structure Two key functions of the?urinary system?are: To?filter waste?products from the blood and expel it from t...
Edexcel IGCSE Biology 復(fù)習(xí)筆記 2.9.2 Excretion in Humans The Organs of Excretion Humans have organs that are specialised for the removal of certain excretory products Excretory organs?of the...
Edexcel IGCSE Biology 復(fù)習(xí)筆記 2.9.1 Excretion The Need for Excretion in Humans Many of the necessary?metabolic reactions?that take place within the cells of organisms produce?waste products...
