AQA A Level Biology复习笔记7.1.1 Key Terms in Genetics
Key Terms in Genetics Genes & alleles The DNA contained within chromosomes is essential for cell survival Every?chromosome?consists of a long DNA molecule which?codes for several differe...
AQA A Level Biology复习笔记6.4.1 Principles of Homeostasis
Homeostasis In order to?function?properly and?efficiently, organisms have different?control systems?that ensure their?internal conditions?are kept relatively?constant Physiological control systems ...
Edexcel IGCSE Maths 复习笔记 1.7.1 Basic Percentages
Edexcel IGCSE Maths复习笔记 1.7.1 Basic Percentages What is a percentage? “Per-cent” simply means “ ÷ 100” (or “out of 100”) You can think of a percentage as a standardised way of expressing a frac...
AQA A Level Biology复习笔记6.3.1 Muscle Pairs
Muscle Pairs The?effective movement?of the human body requires both?muscle?and an?incompressible skeleton This is because muscles will only produce effective movement if they?pull on a structure?th...
AQA A Level Biology复习笔记6.2.1 Neurones
Myelinated Motor Neurones Information is sent through the nervous system as?nerve impulses?– electrical signals that pass along nerve cells known as?neurones A bundle of neurones is known as a nerv...
AQA A Level Biology复习笔记6.1.1 Survival & Response
Responding to Change Aids Survival Organisms must respond to changes in their environment in order to survive They can only survive if they are successful at: Finding favourable conditions for livi...
AQA A Level Biology复习笔记5.4.1 Nutrient Cycles
Nutrient Cycles Living organisms require?nutrients?from their?environments?for?growth?and other processes (e.g. reproduction) These nutrients are then?returned?to the environment when organisms pro...
AQA A Level Biology复习笔记5.3.1 Primary Producers
Plants are Primary Producers An?ecosystem?in a?particular area?includes: All the?living?components (i.e.?biotic factors?such as organisms and their interactions) All the?non-living?components (i.e....
AQA A Level Biology复习笔记5.2.1 Mitochondria & the Need for Energy
Structure & Function of the Mitochondria Mitochondria are rod-shaped organelles 0.5 - 1.0 μm in diameter They are the site of aerobic respiration in eukaryotic cells The function of mitochondri...
