AQA A Level Biology复习笔记4.3.1 Genetic Mutations
Genetic Mutations A gene mutation is a change in the sequence of base pairs in a DNA molecule that may result in an altered polypeptide Mutations occur continuously As the DNA base sequence determi...
AQA A Level Biology复习笔记4.2.1 The Genome
The Genome A gene is a length of DNA that codes for a polypeptide/protein A genome is the complete set of genes present in a cell The full genome is present within every cell of an organism, but no...
AQA A Level Biology复习笔记4.1.1 Prokaryotic DNA
DNA in Prokaryotes The DNA in prokaryotic cells is significantly different from the DNA found in eukaryotic cells “Prokaryote” means “before the nucleus” The DNA is double-stranded Prokaryotes poss...
AQA A Level Biology复习笔记3.6.1 Water Transport in the Xylem
Water & Mineral Ion Transport: Pathways & Mechanisms Within a plant mineral ions and organic compounds (eg. sucrose) are transported by being dissolved in water. The dissolved mineral ions ...
AQA A Level Biology复习笔记3.5.1 Mammalian Circulation
Blood Circulation in Mammals The need for a circulatory system The cells of all living organisms need a constant supply of reactants for metabolism, e.g. oxygen and glucose Single celled organisms ...
AQA A Level Biology复习笔记3.4.1 Features of Mass Transport
Mass Transport The need for a circulatory system The cells of all living organisms need a constant supply of reactants for metabolism, e.g. oxygen and glucose Single celled organisms can gain oxyge...
AQA A Level Biology复习笔记3.3.1 Digestion
The Process of Digestion Digestion is a process in which relatively large, insoluble biological molecules in food (such as starch, proteins) are hydrolysed into smaller, soluble molecules that can ...
AQA A Level Biology复习笔记3.2.1 The Human Gas Exchange System
The Human Gas Exchange System: Structure Gas exchange takes place in the human thorax. This is a collection of organs and tissues in the chest cavity The main structures of the human gas exc...
AQA A Level Biology复习笔记3.1.1 Surface Area to Volume Ratio
Surface Area to Volume Ratio Surface area and volume are both very important factors in the exchange of materials in organisms The surface area refers to the total area of the organism that is expo...
