AQA A Level Biology复习笔记1.6.4 Inorganic Ions
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...
AQA A Level Biology复习笔记1.6.3 The Properties of Water
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
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...
AQA A Level Biology复习笔记1.6.2 Hydrolysis & Synthesis of ATP
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...
AQA A Level Biology复习笔记1.5.10 The Watson Crick Model
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
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...
AQA A Level Biology复习笔记1.5.9 Calculating the Frequency of Nucleotide Bases
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 ...
AQA A Level Biology复习笔记 1.5.8 The Process of Semi-Conservative Replication
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...
AQA A Level Biology复习笔记 1.5.7 Semi-Conservative Replication
The Purpose of Semi-Conservative Replication Before a (parent) cell divides, it needs to copy the DNA contained within it This is so that the two new (daughter) cells produced will both rece...
