AQA A Level Biology复习笔记6.2.4 The Refractory Period
The Refractory Period Very shortly (about 1 ms)?after an action potential?has been generated in a section of the axon membrane, all the?sodium ion voltage-gated channel proteins in this sect...
AQA A Level Biology复习笔记6.2.3 Nerve Impulses
Action Potentials Neurones?transmit?electrical impulses, which travel extremely quickly along the neurone?cell surface membrane?from one end of the neurone to the other Unlike a normal elect...
AQA A Level Biology复习笔记6.2.2 Resting Potentials
Resting Potentials Neurones?transmit?electrical impulses, which travel extremely quickly along the neurone?cell surface membrane?from one end of the neurone to the other In a?resting axon?(o...
AQA A Level Biology复习笔记6.1.14 Calculating Cardiac Output
Calculating Cardiac Output Cardiac output?(CO) is the term used to describe the volume of blood that is pumped by the heart (the left and right ventricle) per unit of time An average adult h...
AQA A Level Biology复习笔记6.1.13 The Autonomic Nervous System
The Autonomic Nervous System There are several circumstances that can cause an individual's heart rate to increase, such as during exercise The?brain?is involved in this response of the hear...
AQA A Level Biology复习笔记6.1.12 Investigating Variables that Affect Heart Rate
Investigating Variables that Affect Heart Rate There are a wide range of factors that influence the heart rate of an organism Experiments can be designed to investigate the effect of a named...
AQA A Level Biology复习笔记6.1.11 Myogenic Stimulation of the Heart
Heart Action: Initiation & Control Control of the basic heartbeat is?myogenic, which means the heart will beat without any external stimulus This intrinsic rhythm means the heart beats a...
AQA A Level Biology复习笔记6.1.10 The Human Retina
The Human Retina The eye is a?sense organ?containing receptors sensitive to light intensity and colour Receptors?are groups of specialised cells that can generate an electrical impulse in a ...
AQA A Level Biology复习笔记6.1.9 Investigating Touch and Temperature Receptors
Investigating Touch and Temperature Receptors on Skin Within the human skin, there are many temperature and touch receptors that enable humans to interpret and respond to their environment E...
