Correlations & Causal Relationships - The Heart Correlation is an association or relationship between variables Causation occurs when one variable has an influence or is influenced by, a...
Interpreting Data Relating to the Cardiovascular System A cardiac cycle is the sequence of events that make up a single heartbeat It includes periods of heart muscle contraction and relaxati...
Capillaries & Tissue Fluid Capillaries are another type of blood vessel present in the circulatory system They have thin walls which are “leaky”, allowing substances to leave the blood t...
Arteries, Arterioles & Veins The body contains several different types of blood vessel: Arteries: transport blood away from the heart (usually at high pressure) Veins: transport blood to...
Apparatus & Techniques: Investing Factors Affecting Heart Rate There are a wide range of factors that influence the heart rate of an organism Experiments can be designed to investigate t...
Edexcel IGCSE Maths 复习笔记 3.11.1 Differentiation - Basics What is differentiation? Differentiation is part of the branch of mathematics called Calculus It is concerned with the rate at which cha...
Edexcel IGCSE Maths 复习笔记 3.10.1 Solving Equations using Graphs How do we use graphs to solve equations? Solutions are always read off the x-axis Solutions of f(x) = 0 are where the graph of y =...
The Cardiac Cycle The contraction of the heart is called systole, while the relaxation of the heart is called diastole Atrial systole is the period when the atria are contracting and ventric...
The Walls of the Heart The muscular walls of the atria are thinner than those of the ventricles When the atria contract, the thin muscular walls do not generate much pressure, but enough to ...
