Edexcel IGCSE Maths 复习笔记 2.4.4 Factorising Quadratics - General What is a quadratic expression? A quadratic expression looks like this:ax2 + bx + c (as long as a ≠ 0) Note: If there are any hig...
Inorganic Ions An ion is an atom (or sometimes a group of atoms) that has an electrical charge An ion that has a +ve charge is known as a cation An ion that has a -ve charge is known as an a...
Water in Cells Water is of great biological importance. It is the medium in which all metabolic reactions take place in cells. Between 70% to 95% of the mass of a cell is water As 71% of the...
Edexcel IGCSE Maths 复习笔记 2.4.3 Difference of Two Squares What is the difference of two squares? A “Difference Of Two Squares” is any expression in the form p2 – q2 Why is it so important? It co...
Hydrolysis of ATP Energy released during the reactions of respiration is transferred to the molecule adenosine triphosphate (ATP) ATP is a small and soluble molecule that provides a short-te...
Evaluating the Watson-Crick Model Watson and Crick were two scientists who worked together to confirm the double-helix structure of DNA in 1953 Watson and Crick also came up with a model by ...
Edexcel IGCSE Maths 复习笔记 2.4.2 Factorising Quadratics - Harder What is a quadratic expression? A quadratic expression looks like this:ax2 + bx + c (as long as a ≠ 0) Note: If there are any high...
Maths Skill: Frequency of Bases All DNA nucleotides contain the same phosphate group and deoxyribose sugar. The nitrogenous base attached to the sugar can vary between nucleotides There are ...
The Process of Semi-Conservative Replication DNA replication occurs in preparation for mitosis, when a parent cell divides to produce two genetically identical daughter cells – as each daugh...
