Exocrine Pancreatic & Palisade Mesophyll Cells Exocrine gland cells of the pancreas The pancreas contains two types of gland cells: endocrine and exocrine cells The function of the exocrine gla...
Eukaryotic Cell Structure Compartmentalized cell structure Eukaryotic cells have a more complex ultrastructure than prokaryotic cells The cytoplasm of eukaryotic cells is divided up into membrane-b...
Prokaryotic Cell Structure The cell structure of organisms determines whether they are prokaryotic or eukaryotic Prokaryotes have the simplest cell structure, being the first organisms to evolve on...
Endosymbiotic Theory Endosymbiosis Endosymbiosis is where one organism lives within another If the relationship is beneficial to both organisms the engulfed organism is not digested For endosymbios...
Spontaneous Generation Pre-existing cells In 1852 Robert Remak made the conclusion that cells divided to form new cells, that is cells came from pre-existing cells His conclusion was reached after ...
Practical 1: Using a Microscope Many biological structures are too small to be seen by the naked eye Optical (light) microscopes are an invaluable tool for scientists as they allow for tissues, cel...
Stem Cells A stem cell is a cell that can divide (by mitosis) an unlimited number of times Each new cell (produced when a stem cell divides) has the potential to remain a stem cell or to develop in...
Emergent Properties Multicellular organisms are able to undertake functions that unicellular organisms cannot, e.g. move over vast distances and digest large macromolecules This is a result of prop...
新学期来了，相信又有一批新同学和家长开始接触AP体系了。美国的AP课程大概有几十门，国内开设的课程可能只有十几门。也就是说，AP课程的选择有一定限制。 同学们需要思考未来的专业意向。因为AP课程是比较灵活的...
Functions of Life Unicellular (single-celled) and multicellular (many cells) organisms must carry out the following functions to stay alive: Metabolism - all the enzyme-catalysed reactions occurrin...
Cell Theory Until microscopes became powerful enough to view individual cells, no-one knew for certain what living organisms were made from A scientist called Robert Hooke came up with the term "ce...
Measuring Half-Life Half-life is defined as: The time taken for the initial number of nuclei to halve for a particular isotope This means when a time equal to the half-life has passed, the activity...
