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 ...
A-level选课需要围绕大学目标专业，以及个人兴趣和能力来进行。 学四门A-level难度如何？ 很多同学认为考四门A-level会很难，会占用更多时间，或许没必要。大学申请也只需要三门A-level。 话虽如此，但很多学生还...
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...
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...
Edexcel IGCSE Maths 复习笔记 2.4.1 Factorising Quadratics - Basics 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...
Appreciating How the Function of DNA Was Determined DNA was actually first observed in the 1800s by a Swiss scientist called Friedrich Miescher Miescher is credited with being the first pers...
Ribosomes Ribosomes are small organelles that are either free in the cytoplasm (of all cells) or are attached to the rough endoplasmic reticulum (only in eukaryotic cells) Ribosomes are the ...
The Structure of RNA Like DNA, the nucleic acid RNA (ribonucleic acid) is a polynucleotide – it is made up of many nucleotides linked together in a chain Like DNA, RNA nucleotides contain th...
Edexcel IGCSE Maths 复习笔记 2.3.3 Expanding Three Brackets Expanding three brackets We’re still following the basic principle of expanding here – get rid of the brackets by multiplying out We just...
The Structure of DNA The nucleic acid DNA is a polynucleotide – it is made up of many nucleotides bonded together in a long chain A DNA nucleotide DNA molecules are made up of two pol...
Nucleotide Structure & the Phosphodiester Bond Both DNA and RNA are polymers that are made up of many repeating units called nucleotides Each nucleotide is formed from: A pentose sugar (...
大家都知道今年AP成绩的正式放榜时间是7月5日，但是这两天AP考试中心的副总裁特雷弗·帕克（Trevor Packer），突然连夜在社交平台上陆续发布了2022年的AP成绩的5分率数据！ 这份数据包括了五门科目的成绩，分别为...
